| 1. |
- van Meurs, Joyce B, et al.
(författare)
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Large-scale analysis of association between LRP5 and LRP6 variants and osteoporosis.
- 2008
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Ingår i: JAMA : the journal of the American Medical Association. - Chicago : American Medical Association (AMA). - 1538-3598 .- 0098-7484. ; 299:11, s. 1277-90
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: Mutations in the low-density lipoprotein receptor-related protein 5 (LRP5) gene cause rare syndromes characterized by altered bone mineral density (BMD). More common LRP5 variants may affect osteoporosis risk in the general population. OBJECTIVE: To generate large-scale evidence on whether 2 common variants of LRP5 (Val667Met, Ala1330Val) and 1 variant of LRP6 (Ile1062Val) are associated with BMD and fracture risk. DESIGN AND SETTING: Prospective, multicenter, collaborative study of individual-level data on 37,534 individuals from 18 participating teams in Europe and North America. Data were collected between September 2004 and January 2007; analysis of the collected data was performed between February and May 2007. Bone mineral density was assessed by dual-energy x-ray absorptiometry. Fractures were identified via questionnaire, medical records, or radiographic documentation; incident fracture data were available for some cohorts, ascertained via routine surveillance methods, including radiographic examination for vertebral fractures. MAIN OUTCOME MEASURES: Bone mineral density of the lumbar spine and femoral neck; prevalence of all fractures and vertebral fractures. RESULTS: The Met667 allele of LRP5 was associated with reduced lumbar spine BMD (n = 25,052 [number of participants with available data]; 20-mg/cm2 lower BMD per Met667 allele copy; P = 3.3 x 10(-8)), as was the Val1330 allele (n = 24,812; 14-mg/cm2 lower BMD per Val1330 copy; P = 2.6 x 10(-9)). Similar effects were observed for femoral neck BMD, with a decrease of 11 mg/cm2 (P = 3.8 x 10(-5)) and 8 mg/cm2 (P = 5.0 x 10(-6)) for the Met667 and Val1330 alleles, respectively (n = 25 193). Findings were consistent across studies for both LRP5 alleles. Both alleles were associated with vertebral fractures (odds ratio [OR], 1.26; 95% confidence interval [CI], 1.08-1.47 for Met667 [2001 fractures among 20 488 individuals] and OR, 1.12; 95% CI, 1.01-1.24 for Val1330 [1988 fractures among 20,096 individuals]). Risk of all fractures was also increased with Met667 (OR, 1.14; 95% CI, 1.05-1.24 per allele [7876 fractures among 31,435 individuals)]) and Val1330 (OR, 1.06; 95% CI, 1.01-1.12 per allele [7802 fractures among 31 199 individuals]). Effects were similar when adjustments were made for age, weight, height, menopausal status, and use of hormone therapy. Fracture risks were partly attenuated by adjustment for BMD. Haplotype analysis indicated that Met667 and Val1330 variants both independently affected BMD. The LRP6 Ile1062Val polymorphism was not associated with any osteoporosis phenotype. All aforementioned associations except that between Val1330 and all fractures and vertebral fractures remained significant after multiple-comparison adjustments. CONCLUSIONS: Common LRP5 variants are consistently associated with BMD and fracture risk across different white populations. The magnitude of the effect is modest. LRP5 may be the first gene to reach a genome-wide significance level (a conservative level of significance [herein, unadjusted P < 10(-7)] that accounts for the many possible comparisons in the human genome) for a phenotype related to osteoporosis.
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| 2. |
- Kaneda, Atsushi, et al.
(författare)
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Enhanced sensitivity to IGF-II signalling links loss of imprinting of IGF2 to increased cell proliferation and tumour risk
- 2007
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 104:52, s. 20926-20931
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Tidskriftsartikel (refereegranskat)abstract
- Loss of imprinting (LOI) of the insulin-like growth factor-II gene (IGF2), leading to abnormal activation of the normally silent maternal allele, is a common human epigenetic population variant associated with a 5-fold increased frequency of colorectal neoplasia. Here, we show first that LOI leads specifically to increased expression of proliferation-related genes in mouse intestinal crypts. Surprisingly, LOI(+) mice also have enhanced sensitivity to IGF-II signaling, not simply increased IGF-II levels, because in vivo blockade with NVP-AEW541, a specific inhibitor of the IGF-II signaling receptor, showed reduction of proliferation-related gene expression to levels half that seen in LOI(-) mice. Signal transduction assays in microfluidic chips confirmed this enhanced sensitivity with marked augmentation of Akt/PKB signaling in LOI(+) cells at low doses of IGF-II, which was reduced in the presence of the inhibitor to levels below those found in LOI(-) cells, and was associated with increased expression of the IGF1 and insulin receptor genes. We exploited this increased IGF-II sensitivity to develop an in vivo chemopreventive strategy using the azoxymethane (AOM) mutagenesis model. LOI(+) mice treated with AOM showed a 60% increase in premalignant aberrant crypt foci (ACF) formation over LOI(-) mice. In vivo IGF-II blockade with NVP-AEW541 abrogated this effect, reducing ACF to a level 30% lower even than found in exposed LOI(-) mice. Thus, LOI increases cancer risk in a counterintuitive way, by increasing the sensitivity of the IGF-II signaling pathway itself, providing a previously undescribed epigenetic chemoprevention strategy in which cells with LOI are "IGF-II addicted" and undergo reduced tumorigenesis in the colon upon IGF-II pathway blockade.
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| 3. |
- Greenhalgh, Christopher J, et al.
(författare)
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SOCS2 negatively regulates growth hormone action in vitro and in vivo.
- 2005
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Ingår i: The Journal of clinical investigation. - 0021-9738. ; 115:2, s. 397-406
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Tidskriftsartikel (refereegranskat)abstract
- Mice deficient in SOCS2 display an excessive growth phenotype characterized by a 30-50% increase in mature body size. Here we show that the SOCS2-/- phenotype is dependent upon the presence of endogenous growth hormone (GH) and that treatment with exogenous GH induced excessive growth in mice lacking both endogenous GH and SOCS2. This was reflected in terms of overall body weight, body and bone lengths, and the weight of internal organs and tissues. A heightened response to GH was also measured by examining GH-responsive genes expressed in the liver after exogenous GH administration. To further understand the link between SOCS2 and the GH-signaling cascade, we investigated the nature of these interactions using structure/function and biochemical interaction studies. Analysis of the 3 structural motifs of the SOCS2 molecule revealed that each plays a crucial role in SOCS2 function, with the conserved SOCS-box motif being essential for all inhibitory function. SOCS2 was found to bind 2 phosphorylated tyrosines on the GH receptor, and mutational analysis of these amino acids showed that both were essential for SOCS2 function. Together, the data provide clear evidence that SOCS2 is a negative regulator of GH signaling.
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| 4. |
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| 5. |
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| 6. |
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| 7. |
- Lonn, Stefan, et al.
(författare)
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Long-term mobile phone use and brain tumor risk
- 2005
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Ingår i: American Journal of Epidemiology. - : Oxford University Press (OUP). - 0002-9262 .- 1476-6256. ; 161:6, s. 526-535
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Tidskriftsartikel (refereegranskat)abstract
- Handheld mobile phones were introduced in Sweden during the late 1980s. The purpose of this population-based, case-control study was to test the hypothesis that long-term mobile phone use increases the risk of brain tumors. The authors identified all cases aged 20-69 years who were diagnosed with glioma or meningioma during 2000-2002 in certain parts of Sweden. Randomly selected controls were stratified on age, gender, and residential area. Detailed information about mobile phone use was collected from 371 (74%) glioma and 273 (85%) meningioma cases and 674 (71%) controls. For regular mobile phone use, the odds ratio was 0.8 (95% confidence interval: 0.6, 1.0) for glioma and 0.7 (95% confidence interval: 0.5, 0.9) for meningioma. Similar results were found for more than 10 years' duration of mobile phone use. No risk increase was found for ipsilateral phone use for tumors located in the temporal and parietal lobes. Furthermore, the odds ratio did not increase, regardless of tumor histology, type of phone, and amount of use. This study includes a large number of long-term mobile phone users, and the authors conclude that the data do not support the hypothesis that mobile phone use is related to an increased risk of glioma or meningioma.
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| 8. |
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| 9. |
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| 10. |
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| 11. |
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| 12. |
- Svensson, L., et al.
(författare)
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Comparison of very early treatment with either fibrinolysis or percutaneous coronary intervention facilitated with abciximab with respect to ST recovery and infarct-related artery epicardial flow in patients with acute ST-segment elevation myocardial infarction: the Swedish Early Decision (SWEDES) reperfusion trial
- 2006
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Ingår i: Am Heart J. - : Mosby, Inc.. - 1097-6744 .- 0002-8703. ; 151:4
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Results from a number of studies indicate that primary percutaneous coronary intervention (PCI) is superior to fibrinolysis for treatment of acute ST-elevation myocardial infarction. Modern adjunctive antithrombotic treatment with systematic use of low-molecular-weight heparins, fibrin-specific thrombolysis, and glycoprotein IIb/IIIa receptor inhibitors may improve the outcome compared with what was achieved in previous studies. METHODS: Patients with ST-elevation myocardial infarction were randomized to receive enoxaparin followed by reteplase (group A; n = 104) or enoxaparin followed by abciximab and transfer to invasive center for optional PCI (group B; n = 101). Primary end points were ST-segment resolution 120 minutes and TIMI flow at coronary angiography 5 to 7 days after randomization. RESULTS: Forty-two percent of the patients started therapy in the prehospital phase. Time from symptom to treatment was 114 minutes in group A and 202 minutes in group B. Baseline characteristics were similar in the 2 groups. Sixty-four percent in group A and 68% in group B had ST resolution of > 50% at 120 minutes (not significant). At control angiography, 54% in the fibrinolytic group and 71% in the invasive group had TIMI 3 flow (P = .04). At 30 days, the composite of death, stroke, or reinfarction occurred in 8% in the fibrinolytic group compared with 3% in the invasive group (not significant). CONCLUSIONS: Despite much shorter time delay to start of fibrinolysis than PCI, this did not result in signs of superior myocardial reperfusion. Epicardial flow in the infarct-related artery was better after invasive therapy, and there was a trend toward better clinical outcome after this treatment compared with after fibrinolysis.
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| 13. |
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| 14. |
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| 15. |
- Werner, M, et al.
(författare)
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Autoimmune hepatitis in Sweden.
- 2007
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Ingår i: SCANDINAVIAN JOURNAL OF GASTROENTEROLOGY. - 0036-5521. ; 42, s. 15-15
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 16. |
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| 18. |
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| 19. |
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| 20. |
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| 21. |
- Duan, Rui-Dong, et al.
(författare)
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Human meconium contains significant amounts of alkaline sphingomyelinase, neutral ceramidase, and sphingolipid metabolites.
- 2007
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Ingår i: Pediatric Research. - : Springer Science and Business Media LLC. - 1530-0447 .- 0031-3998. ; 61:1, s. 61-66
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Tidskriftsartikel (refereegranskat)abstract
- Intestinal alkaline sphingomyelinase (Alk-SMase) and neutral ceramidase may catalyze the hydrolysis of endogenous sphin-gomyelin (SM) and milk SM in human-milk fed infants. The enzymes generate sphingolipid metabolites that may influence gut maturation. Alk-SMase also inactivates platelet-activating factor (PAF) that is involved in the pathogenesis of necrotizing enterocolitis (NEC). We examined whether the two enzymes are expressed in both preterm and term infants and analyzed Alk-SMase, neutral ceramidase, SM, and sphingolipid metabolites in meconium. Meconium was collected from 46 preterm (gestational ages 23-36 wk) and 38 term infants (gestational ages 37-42 wk) and analyzed for Alk-SMase using C-14-choline-labeled SM and for neutral ceramidase using C-14-octanoyl-sphingosine as substrates. Molecular species of SM, ceramide, and sphingosine were analyzed by high-performance liquid chromatography mass spectroscopy. Meconium contained significant levels of Alk-SMase and ceramidase at all gestational ages. It also contained 16-24 carbon molecular species of SM, palmitoyl-and stearoyl-sphingosine, and sphingosine. There were positive correlations between levels of SM and ceramide and between ceramide and sphingosine levels. In conclusion, Alk-SMase and ceramidase are expressed in the gut of both preterm and term newborn infants and may generate bioactive sphingolipid messengers.
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| 22. |
- Egecioglu, Emil, 1977, et al.
(författare)
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Central NMU signaling in body weight and energy balance regulation: evidence from NMUR2 deletion and chronic central NMU treatment in mice.
- 2009
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Ingår i: American journal of physiology. Endocrinology and metabolism. - : American Physiological Society. - 1522-1555 .- 0193-1849. ; 297:3
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Tidskriftsartikel (refereegranskat)abstract
- To investigate the role of the central neuromedin U (NMU) signaling system in body weight and energy balance regulation, we examined the effects of long-term intracerebroventricular (icv) infusion of NMU in C57Bl/6 mice and in mice lacking the gene encoding NMU receptor 2. In diet-induced obese male and female C57BL/6 mice, icv infusion of NMU (8 microg x day(-1) x mouse(-1)) for 7 days decreased body weight and total energy intake compared with vehicle treatment. However, these parameters were unaffected by NMU treatment in lean male and female C57BL/6 mice fed a standard diet. In addition, female (but not male) NMUR2-null mice had increased body weight and body fat mass when fed a high-fat diet but lacked a clear body weight phenotype when fed a standard diet compared with wild-type littermates. Furthermore, female (but not male) NMUR2-null mice fed a high-fat diet were protected from central NMU-induced body weight loss compared with littermate wild-type mice. Thus, we provide the first evidence that long-term central NMU treatment reduces body weight, food intake, and adiposity and that central NMUR2 signaling is required for these effects in female but not male mice.
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| 23. |
- Estrada, Karol, et al.
(författare)
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A genome-wide association study of northwestern Europeans involves the C-type natriuretic peptide signaling pathway in the etiology of human height variation.
- 2009
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Ingår i: Human molecular genetics. - : Oxford University Press (OUP). - 1460-2083 .- 0964-6906. ; 18:18, s. 3516-24
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Tidskriftsartikel (refereegranskat)abstract
- Northwestern Europeans are among the tallest of human populations. The increase in body height in these people appears to have reached a plateau, suggesting the ubiquitous presence of an optimal environment in which genetic factors may have exerted a particularly strong influence on human growth. Therefore, we performed a genome-wide association study (GWAS) of body height using 2.2 million markers in 10 074 individuals from three Dutch and one German population-based cohorts. Upon genotyping, the 12 most significantly height-associated single nucleotide polymorphisms (SNPs) from this GWAS in 6912 additional individuals of Dutch and Swedish origin, a genetic variant (rs6717918) on chromosome 2q37.1 was found to be associated with height at a genome-wide significance level (P(combined) = 3.4 x 10(-9)). Notably, a second SNP (rs6718438) located approximately 450 bp away and in strong LD (r(2) = 0.77) with rs6717918 was previously found to be suggestive of a height association in 29 820 individuals of mainly northwestern European ancestry, and the over-expression of a nearby natriuretic peptide precursor type C (NPPC) gene, has been associated with overgrowth and skeletal anomalies. We also found a SNP (rs10472828) located on 5p14 near the natriuretic peptide receptor 3 (NPR3) gene, encoding a receptor of the NPPC ligand, to be associated with body height (P(combined) = 2.1 x 10(-7)). Taken together, these results suggest that variation in the C-type natriuretic peptide signaling pathway, involving the NPPC and NPR3 genes, plays an important role in determining human body height.
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| 24. |
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| 25. |
- Flöter, A, et al.
(författare)
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Effects of combined estrogen/testosterone therapy on bone and body composition in oophorectomized women.
- 2005
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Ingår i: Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology. - : Informa UK Limited. - 0951-3590. ; 20:3, s. 155-60
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To evaluate the effect of adding testosterone undecanoate 40 mg daily to estrogen therapy on bone markers, bone mineral density and body composition in oophorectomized women. METHODS: Fifty women, 45-60 years old, who had undergone a hysterectomy and bilateral salpingo-oophorectomy for benign disorders, were randomly assigned to oral treatment with testosterone undecanoate 40 mg plus estradiol valerate 2 mg daily or placebo plus estradiol valerate 2 mg daily. Twenty-four weeks later, cross-over was performed to the other treatment regimen. Forty-four women completed the study. Their serum concentrations of insulin-like growth factor (IGF)-I, IGF binding protein (IGFBP)-3, osteocalcin, carboxyterminal telopeptide aminoterminal (ICTP), of type I collagen propeptide of type I procollagen (PICP) and interleukin (IL)-1 receptor antagonist were measured at baseline and after 24 weeks of both treatments, as were also their body mass index (BMI) and blood pressure. Bone mineral density of the total body, spine and hip and total body fat, total lean body mass, trunk fat and trunk lean mass were determined by dual-energy X-ray absorptiometry measurements at baseline and after 24 weeks of both regimens. RESULTS: During treatment, the addition of testosterone counteracted the decrease in IGF-I and PICP seen with estrogen therapy alone. Osteocalcin and ICTP were significantly reduced to the same extent by both therapies. No change ocurred in the IL-1 receptor antagonist. A significant increase was seen in total lean body mass with the estrogen/testosterone regimen, but the total fat mass, trunk lean or fat mass remained unchanged after 24 weeks of both treatments. No effect was detected on total, hip or spinal bone mineral density after treatment with estrogen alone or estrogen/testosterone. Likewise, BMI and blood pressure were unaffected. CONCLUSIONS: The addition of testosterone to oral estrogen might have positive effects on bone as suggested by the fact that it counteracted the decline in IGF-I and PICP levels. An anabolic effect on muscle was reflected by an increase in the total lean body mass. No adverse effects were noted on BMI, fat distribution or blood pressure during the 6-month treatment with oral testosterone undecanoate.
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| 26. |
- Gondor, A, et al.
(författare)
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Chromosome crosstalk in three dimensions
- 2009
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 461:7261, s. 212-217
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Tidskriftsartikel (refereegranskat)
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| 27. |
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| 28. |
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| 29. |
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| 30. |
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| 31. |
- Islander, Ulrika, 1975, et al.
(författare)
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Estren-mediated inhibition of T lymphopoiesis is estrogen receptor-independent whereas its suppression of T cell-mediated inflammation is estrogen receptor-dependent
- 2005
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Ingår i: Clin Exp Immunol. - : Oxford University Press (OUP). - 0009-9104 .- 1365-2249. ; 139:2, s. 210-5
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Tidskriftsartikel (refereegranskat)abstract
- Estrogen has extensive effects on the immune system. The aim of the present experiments was to compare the effects of 17beta-estradiol (E2) and 4-estren-3alpha,17beta-diol (estren) on T lymphopoiesis and T cell-dependent inflammation. In order to investigate the role of estrogen receptors (ER) in the effects of E2 and estren on the immune system, ER knock-out mice lacking both ERalpha and ERbeta (DERKO) were used. T lymphopoiesis and T cell-dependent inflammation were studied by investigating thymus cellularity, the delayed-type hypersensitivity (DTH) reaction, CD4(+) T cells in spleen and serum levels of interleukin (IL)-6. As expected, the presence of ERs was mandatory for all the effects of E2. In contrast, treatment with estren reduced thymus cellularity in ER knock-out mice, indicating an effect through ER-independent pathways. Interestingly, estren suppressed only DTH, the frequency of CD4(+) T cells in spleen and serum levels of IL-6 in wild-type (WT) mice, but not in mice lacking ERs. Thus, our study is the first to show that estren inhibits T lymphopoiesis via ER-independent pathways, whereas its suppressive effects on inflammation are ER-dependent.
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| 32. |
- Islander, Ulrika, 1975, et al.
(författare)
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Estren promotes androgen phenotypes in primary lymphoid organs and submandibular glands
- 2005
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Ingår i: BMC Immunology. - : Springer Science and Business Media LLC. - 1471-2172. ; 12:6
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Estrogens and androgens have extensive effects on the immune system, for example they suppress both T and B lymphopoiesis in thymus and bone marrow. Submandibular glands are sexually dimorphic in rodents, resulting in larger granular convoluted tubules in males compared to females. The aim of the present experiments was to investigate the estrogenic and androgenic effects of 4-estren-3alpha,17beta-diol (estren) on thymus, bone marrow and submandibular glands, and compare the effects to those of 17beta-estradiol (E2) and 5alpha-dihydrotestosterone (DHT), respectively. Estrogen receptors (ERs) were blocked by treatment of mice with the ER-antagonist ICI 182,780; also, knock-out mice lacking one or both ERs were used. RESULTS: As expected, the presence of functional ERs was mandatory for all the effects of E2. Similar to DHT-treatment, estren-treatment resulted in decreased thymus weight, as well as decreased frequency of bone marrow B cells. Treatment with estren or DHT also resulted in a shift in submandibular glands towards an androgen phenotype. All the effects of estren and DHT were independent of ERs. CONCLUSION: Our study is the first to show that estren has similar effects as the androgen DHT on lymphopoiesis in thymus and bone marrow, and on submandibular glands, and that these effects are independent of estrogen receptors. This supports the hypothesis of estren being able to signal through the androgen receptor.
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| 33. |
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| 34. |
- Karimian, Elham, et al.
(författare)
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Tamoxifen impairs both longitudinal and cortical bone growth in young male rats.
- 2008
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Ingår i: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. - : Wiley. - 1523-4681. ; 23:8, s. 1267-77
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Tidskriftsartikel (refereegranskat)abstract
- Tamoxifen (Tam) has been used experimentally to treat boys with gynecomastia and girls with McCune-Albright syndrome. This drug was recently shown to inhibit the growth of cultured fetal rat metatarsal bones and thus might also affect bone growth in vivo. Four-week-old Sprague-Dawley rats were gavaged daily with vehicle alone (peanut oil), Tam (40 mg/kg/d; 1 or 4 wk), or estradiol (40 microg/kg/d; 4 wk). Five of the 10 rats in each group were killed after 4 wk and the other five after 14 wk of recovery. Bone growth was followed by repeat DXA scans, whereas other bone parameters and spine length were evaluated by pQCT and X-ray at the time of death. Four-week Tam treatment significantly decreased body weight, nose-anus distance, spinal and tibial bone lengths, trabecular BMD, cortical periosteal circumference, and bone strength and also reduced serum IGF-I levels (424 +/- 54 versus 606 +/- 53 ng/ml in control; p < 0.05). Analysis of the tibial growth plate of treated rats showed elevated chondrocyte proliferation (BrdU) and apoptosis (TUNEL), as well as decreases in the number of hypertrophic chondrocytes and in the size of terminal hypertrophic chondrocytes. Despite a complete catch-up of body weight after 14 wk of recovery, the tibia was still shorter (p < 0.001) and its cortical region was smaller. We conclude that, when administered at a clinically relevant dose, Tam causes persistent retardation of longitudinal and cortical radial bone growth in young male rats. Our findings suggest that this inhibition results from local effects on the growth plate cartilage and systemic suppression of IGF-I production. Based on these rat data, we believe that Tam, if given to growing individuals, might compromise cortical bone growth, bone strength, and adult height.
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| 35. |
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| 36. |
- LeBlanc, Erin S, et al.
(författare)
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The effects of serum testosterone, estradiol, and sex hormone binding globulin levels on fracture risk in older men.
- 2009
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 94:9, s. 3337-46
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: The relationship between sex steroids and fracture is poorly understood. OBJECTIVE: The objective of the study was to examine associations between nonvertebral fracture risk and bioavailable estradiol (bioE2), bioavailable testosterone (bioT), and SHBG. DESIGN: This was a case-cohort study. SETTING: The Osteoporotic Fractures in Men Study (MrOS) was conducted in a prospective U.S. cohort in 5995 community-dwelling men 65 yr old or older. PARTICIPANTS: Participants included a subcohort of 1436 randomly chosen white men plus all 446 minorities and all those with incident hip and other nonvertebral fractures. MAIN OUTCOME MEASURES: Baseline testosterone and estradiol were measured by mass spectrometry (MS) and SHBG by RIA. RESULTS: Men with the lowest bioE2 (<11.4 pg/ml) or highest SHBG (>59.1 nm) had greater risk of all nonvertebral fractures [adjusted hazard ratio (HR) [95% confidence interval]: 1.5 (1.2-1.9) and 1.4 (1.1-21.8), respectively]. Men with the lowest bioT (<163.5 ng/dl) had no increased fracture risk after adjustment for bioE2 [adjusted HR 1.16 (0.90-1.49)]. A significant interaction between SHBG and bioT (P = 0.03) resulted in men with low bioT and high SHBG having higher fracture risk [HR 2.1 (1.4-3.2)]. Men with low bioE2, low bioT, and high SHBG were at highest risk [HR 3.4 (2.2-5.3)]. CONCLUSIONS: Older men with low bioE2 or high SHBG levels are at increased risk of nonvertebral fracture. When SHBG levels are high, men with low bioT levels have higher risk. The strongest association occurred when all measures were considered in combination.
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| 37. |
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| 38. |
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| 39. |
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| 40. |
- Marsell, Richard, et al.
(författare)
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Mice expressing a constitutively active PTH/PTHrP receptor in osteoblasts show reduced callus size but normal callus morphology during fracture healing.
- 2007
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Ingår i: Acta orthopaedica. - : Medical Journals Sweden AB. - 1745-3674 .- 1745-3682. ; 78:1, s. 39-45
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The parathyroid hormone-/parathyroid hormone-related protein (PTH/PTHrP) receptor plays a crucial role in endochondral bone formation and possibly also in fracture healing. Patients with Jansen's metaphysial chondrodysplasia (JMC) have a gain-of-function mutation in the PTH/PTHrP receptor. Transgenic mice expressing JMC PTH/PTHrP receptor mutants in osteoblasts are characterized by increased trabecular bone formation and reduced osteoblastic activity at periosteal sites. We have analyzed the bone phenotype and studied the fracture healing process in this model. METHODS: We performed bone density analysis of tibiae from 17-week-old transgenic mice and controls. Also, tibial fractures were produced in 14-week-old mice. Fracture healing was examined by radiographic and histological analysis. RESULTS: Transgenic mice had a lower total bone mineral content (BMC), by a factor of one-third. The changes were bone compartment-specific with an increase in trabecular bone volume and a decrease in cortical thickness. The calluses in the transgenic mice were smaller, with a reduction in BMC and mean cross-sectional area by a factor of one-half. Despite the smaller size, however, the morphology and progression through the healing process were similar in both transgenic and wild-type littermates. INTERPRETATION: We conclude that the constitutively active PTH/PTHrP receptor has compartment-specific effects on bone formation when expressed in osteoblasts. During fracture healing, however, both the periosteal and the endochondral processes are activated, leading to fracture healing that is temporally and morphologically normal, although the callus tissue is less prominent.
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| 41. |
- Marsell, Richard, et al.
(författare)
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Relation between fibroblast growth factor-23, body weight and bone mineral density in elderly men
- 2009
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Ingår i: Osteoporosis International. - : Springer Science and Business Media LLC. - 0937-941X .- 1433-2965. ; 20:7, s. 1167-1173
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Tidskriftsartikel (refereegranskat)abstract
- We evaluated the relation between serum FGF23 and bone mineral density (BMD) in a community-based cohort of elderly men. There was a weak correlation between FGF23 and BMD, which was primarily dependent on body weight.INTRODUCTION: FGF23 is a hormonal factor produced in bone and regulates serum levels of phosphate (Pi) and vitamin D. FGF23 over-expression is associated with skeletal abnormalities, including rickets/osteomalacia. The relation between FGF23 and Bone Mineral Density (BMD) in the community remains unexplored.METHODS: We employed a large, population-based cohort of 3014 Swedish men aged 69-80 years, without known renal disease. BMD was measured with dual X-ray absorptiometry (DXA) in the hip and lumbar spine. Serum intact FGF23 was analyzed with a two-site monoclonal ELISA.RESULTS: There was a weak but significant correlation between FGF23 and BMD in femoral neck (r = 0.04, p < 0.05), femoral trochanter (r = 0.05, p = 0.004), total hip (r = 0.06, p = 0.0015) and lumbar spine (r = 0.07, p = 0.0004). The correlations remained significant when adjusting for biochemical covariates (Pi, calcium, PTH, 25(OH)D and renal function). However, the association became insignificant in all regions when adjusting for established confounding variables including age, height, weight and smoking. Further analysis confirmed a significant correlation between FGF23 and body weight (r = 0.13, p < 0.0001).CONCLUSIONS: The weak correlation between FGF23 and BMD in elderly male subjects is mainly due to an association between FGF23 and body weight. Therefore, FGF23 may not play a significant role in the hormonal regulation of BMD.
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| 42. |
- Mellström, Dan, 1945, et al.
(författare)
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Older men with low serum estradiol and high serum SHBG have an increased risk of fractures
- 2008
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Ingår i: J Bone Miner Res. - : Wiley. - 1523-4681 .- 0884-0431. ; 23:10, s. 1552-60
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Tidskriftsartikel (refereegranskat)abstract
- Osteoporosis-related fractures constitute a major health concern not only in women but also in men. To study the predictive role of serum sex steroids for fracture risk in men, serum sex steroids were analyzed by the specific gas chromatography-mass spectrometry technique at baseline in older men (n = 2639; mean, 75 yr of age) of the prospective population-based MrOS Sweden cohort. Fractures occurring after baseline were validated (average follow-up of 3.3 yr). The incidence for having at least one validated fracture after baseline was 20.9/1000 person-years. Estradiol (E2; hazard ratio [HR] per SD decrease, 1.34; 95% CI, 1.22-1.49), free estradiol (fE2; HR per SD decrease, 1.41; 95% CI, 1.28-1.55), testosterone (T; HR per SD decrease, 1.27; 95% CI, 1.16-1.39), and free testosterone (fT; HR per SD decrease, 1.32; 95% CI, 1.21-1.44) were all inversely, whereas sex hormone-binding globulin (SHBG; HR per SD increase, 1.41; 95% CI, 1.22-1.63) was directly related to fracture risk. Multivariable proportional hazards regression models, adjusted for age, suggested that fE2 and SHBG (p
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| 43. |
- Minahan, Joseph A., et al.
(författare)
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Finite size effects for giant magnons on physical strings
- 2008
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Ingår i: Nuclear Physics B. - : Elsevier BV. - 0550-3213 .- 1873-1562. ; 801:1-2, s. 97-117
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Tidskriftsartikel (refereegranskat)abstract
- Using finite gap methods, we find the leading order finite size corrections for an arbitrary number of giant magnons on physical strings, where the sum of the momenta is a multiple of 2π. Our results are valid for the Hofman-Maldacena fundamental giant magnons as well as their dyonic generalizations. The energy corrections turn out to be surprisingly simple, especially if all the magnons are fundamental, and at leading order are independent of the magnon flavors. We also show how to use the Bethe ansatz to find finite size corrections for dyonic giant magnons with large R-charges.
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| 44. |
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| 45. |
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| 46. |
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| 47. |
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| 48. |
- Ohlsson, Jörgen, et al.
(författare)
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Structure–activity relationships of galabioside derivatives as inhibitors of E. coli and S. suis adhesins: nanomolar inhibitors of S. suis adhesins
- 2005
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Ingår i: Organic and Biomolecular Chemistry. - : Royal Society of Chemistry (RSC). - 1477-0539 .- 1477-0520. ; 3:5, s. 886-900
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Tidskriftsartikel (refereegranskat)abstract
- Four collections of Gal1-4Gal derivatives were synthesised and evaluated as inhibitors of the PapG class II adhesin of uropathogenic Escherichia coli and of the PN and PO adhesins of Streptococcus suis strains. Galabiosides carrying aromatic structures at C1, methoxyphenyl O-galabiosides in particular, were identified as potent inhibitors of the PapG adhesin. Phenylurea derivatisation at C3 and methoxymethylation at O2 of galabiose provided inhibitors of the S. suis strains type PN adhesin with remarkably high affinities (30 and 50 nM, respectively). In addition, quantitative structure–activity relationship models for E. coli PapG adhesin and S. suis adhesin type PO were developed using multivariate data analysis. The inhibitory lead structures constitute an advancement towards high-affinity inhibitors as potential anti-adhesion therapeutic agents targeting bacterial infections.
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| 49. |
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| 50. |
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