| 1. |
- Kerkhof, H. J. M., et al.
(författare)
-
Recommendations for standardization and phenotype definitions in genetic studies of osteoarthritis: the TREAT-OA consortium
- 2011
-
Ingår i: Osteoarthritis and Cartilage. - : Elsevier BV. - 1063-4584. ; 19:3, s. 254-264
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To address the need for standardization of osteoarthritis (OA) phenotypes by examining the effect of heterogeneity among symptomatic (SOA) and radiographic osteoarthritis (ROA) phenotypes. Methods: Descriptions of OA phenotypes of the 28 studies involved in the TREAT-OA consortium were collected. We investigated whether different OA definitions result in different association results by creating various hip OA definitions in one large population based cohort (the Rotterdam Study I (RSI)) and testing those for association with gender, age and body mass index using one-way ANOVA. For ROA, we standardized the hip-, knee- and hand ROA definitions and calculated prevalence's of ROA before and after standardization in nine cohort studies. This procedure could only be performed in cohort studies and standardization of SOA definitions was not feasible at this moment. Results: In this consortium, all studies with SOA phenotypes (knee, hip and hand) used a different definition and/or assessment of OA status. For knee-, hip- and hand ROA five, four and seven different definitions were used, respectively. Different hip ROA definitions do lead to different association results. For example, we showed in the RSI that hip OA defined as "at least definite joint space narrowing (JSN) and one definite osteophyte" was not associated with gender (P=0.22), but defined as "at least one definite osteophyte" was significantly associated with gender (P=3 x 10(-9)). Therefore, a standardization process was undertaken for ROA definitions. Before standardization a wide range of ROA prevalence's was observed in the nine cohorts studied. After standardization the range in prevalence of knee- and hip ROA was small. Conclusion: Phenotype definitions influence the prevalence of OA and association with clinical variables. ROA phenotypes within the TREAT-OA consortium were standardized to reduce heterogeneity and improve power in future genetics studies. (C) 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
|
|
| 2. |
- Evangelou, Evangelos, et al.
(författare)
-
Meta-analysis of genome-wide association studies confirms a susceptibility locus for knee osteoarthritis on chromosome 7q22
- 2011
-
Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 70:2, s. 349-355
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives Osteoarthritis (OA) is the most prevalent form of arthritis and accounts for substantial morbidity and disability, particularly in older people. It is characterised by changes in joint structure, including degeneration of the articular cartilage, and its aetiology is multifactorial with a strong postulated genetic component. Methods A meta-analysis was performed of four genome-wide association (GWA) studies of 2371 cases of knee OA and 35 909 controls in Caucasian populations. Replication of the top hits was attempted with data from 10 additional replication datasets. Results With a cumulative sample size of 6709 cases and 44 439 controls, one genome-wide significant locus was identified on chromosome 7q22 for knee OA (rs4730250, p = 9.2 x 10(-9)), thereby confirming its role as a susceptibility locus for OA. Conclusion The associated signal is located within a large (500 kb) linkage disequilibrium block that contains six genes: PRKAR2B (protein kinase, cAMP-dependent, regulatory, type II, beta), HPB1 (HMG-box transcription factor 1), COG5 (component of oligomeric golgi complex 5), GPR22 (G protein-coupled receptor 22), DUS4L (dihydrouridine synthase 4-like) and BCAP29 (B cell receptor-associated protein 29). Gene expression analyses of the (six) genes in primary cells derived from different joint tissues confirmed expression of all the genes in the joint environment.
|
|
| 3. |
|
|
| 4. |
- Johansson, Helena, 1981, et al.
(författare)
-
A meta-analysis of the association of fracture risk and body mass index in women.
- 2014
-
Ingår i: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. - : Wiley. - 1523-4681. ; 29:1, s. 223-33
-
Tidskriftsartikel (refereegranskat)abstract
- Several recent studies suggest that obesity may be a risk factor for fracture. The aim of this study was to investigate the association between body mass index (BMI) and future fracture risk at different skeletal sites. In prospective cohorts from more than 25 countries, baseline data on BMI were available in 398,610 women with an average age of 63 (range, 20-105) years and follow up of 2.2 million person-years during which 30,280 osteoporotic fractures (6457 hip fractures) occurred. Femoral neck BMD was measured in 108,267 of these women. Obesity (BMI ≥ 30kg/m(2) ) was present in 22%. A majority of osteoporotic fractures (81%) and hip fractures (87%) arose in non-obese women. Compared to a BMI of 25kg/m(2) , the hazard ratio (HR) for osteoporotic fracture at a BMI of 35kg/m(2) was 0.87 (95% confidence interval [CI], 0.85-0.90). When adjusted for bone mineral density (BMD), however, the same comparison showed that the HR for osteoporotic fracture was increased (HR, 1.16; 95% CI, 1.09-1.23). Low BMI is a risk factor for hip and all osteoporotic fracture, but is a protective factor for lower leg fracture, whereas high BMI is a risk factor for upper arm (humerus and elbow) fracture. When adjusted for BMD, low BMI remained a risk factor for hip fracture but was protective for osteoporotic fracture, tibia and fibula fracture, distal forearm fracture, and upper arm fracture. When adjusted for BMD, high BMI remained a risk factor for upper arm fracture but was also a risk factor for all osteoporotic fractures. The association between BMI and fracture risk is complex, differs across skeletal sites, and is modified by the interaction between BMI and BMD. At a population level, high BMI remains a protective factor for most sites of fragility fracture. The contribution of increasing population rates of obesity to apparent decreases in fracture rates should be explored. © 2014 American Society for Bone and Mineral Research.
|
|
| 5. |
|
|
| 6. |
- Nakajima, K., et al.
(författare)
-
Enhanced diagnostic accuracy for quantitative bone scan using an artificial neural network system: A Japanese multi-center database project
- 2013
-
Ingår i: EJNMMI Research. - 2191-219X. ; 3:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background Artificial neural network (ANN)-based bone scan index (BSI), a marker of the amount of bone metastasis, has been shown to enhance diagnostic accuracy and reproducibility but is potentially affected by training databases. The aims of this study were to revise the software using a large number of Japanese databases and to validate its diagnostic accuracy compared with the original Swedish training database. Methods The BSI was calculated with EXINIbone (EB; EXINI Diagnostics) using the Swedish training database (n = 789). The software using Japanese training databases from a single institution (BONENAVI version 1, BN1, n = 904) and the revised version from nine institutions (version 2, BN2, n = 1,532) were compared. The diagnostic accuracy was validated with another 503 multi-center bone scans including patients with prostate (n = 207), breast (n = 166), and other cancer types. The ANN value (probability of abnormality) and BSI were calculated. Receiver operating characteristic (ROC) and net reclassification improvement (NRI) analyses were performed. Results The ROC analysis based on the ANN value showed significant improvement from EB to BN1 and BN2. In men (n = 296), the area under the curve (AUC) was 0.877 for EB, 0.912 for BN1 (p = not significant (ns) vs. EB) and 0.934 for BN2 (p = 0.007 vs. EB). In women (n = 207), the AUC was 0.831 for EB, 0.910 for BN1 (p = 0.016 vs. EB), and 0.932 for BN2 (p < 0.0001 vs. EB). The optimum sensitivity and specificity based on BN2 was 90% and 84% for men and 93% and 85% for women. In patients with prostate cancer, the AUC was equally high with EB, BN1, and BN2 (0.939, 0.949, and 0.957, p = ns). In patients with breast cancer, the AUC was improved from EB (0.847) to BN1 (0.910, p = ns) and BN2 (0.924, p = 0.039). The NRI using ANN between EB and BN1 was 17.7% (p = 0.0042), and that between EB and BN2 was 29.6% (p < 0.0001). With respect to BSI, the NRI analysis showed downward reclassification with total NRI of 31.9% (p < 0.0001). Conclusion In the software for calculating BSI, the multi-institutional database significantly improved identification of bone metastasis compared with the original database, indicating the importance of a sufficient number of training databases including various types of cancers. © 2013 Nakajima et al.
|
|
| 7. |
|
|
| 8. |
- Yamada, Y., et al.
(författare)
-
Dehydrogenation process of Mg-Ni based switchable mirrors analyzed by in situ spectroscopic ellipsometry
- 2012
-
Ingår i: Solar Energy Materials and Solar Cells. - : Elsevier BV. - 0927-0248 .- 1879-3398. ; 99:SI, s. 84-87
-
Tidskriftsartikel (refereegranskat)abstract
- The dehydrogenation process of hydrogenated switchable mirrors using magnesium-nickel alloy thin film was studied in situ using spectroscopic ellipsometry. Ellipsometric angles Psi and Delta of the switchable mirrors varied drastically as a result of dehydrogenation, which is a transformation from transparent to reflective states. The process was analyzed by dividing into the following three phases. The first phase was the dehydrogenation process of a thin Mg4Ni layer with several nanometers at a hydrogenated Pcl/Mg4Ni interface. The second phase was the dehydrogenation processes of the hydrogenated Mg4Ni layer, which proceeded from the Pd/Mg4Ni interface to the substrate. The final phase was the desorption process of hydrogen, which was absorbed in Mg4Ni as solid solution and the dehydrogenation process was terminated.
|
|
| 9. |
- Yamada, Y, et al.
(författare)
-
In situ spectroscopic ellipsometry study of the hydrogenation process of switchable mirrors based on magnesium-nickel alloy thin films
- 2010
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 107:4, s. 043517-
-
Tidskriftsartikel (refereegranskat)abstract
- The hydrogenation process of switchable mirrors using magnesium-nickel alloy thin films including a thin palladium cap layer was analyzed by measuring the variation in ellipsometric angles Psi and Delta using in situ spectroscopic ellipsometry. The process was divided into three phases and each phase was identified as follows. The first phase was the process in which the solid solution was formed because a Mg-Ni alloy in its metal state absorbs hydrogen. The second phase was the hydrogenation processes of the solid solution and the metal Pd layers. The third phase was the hydrogenation process of residual metal Pd in the Pd layer. In the initial state of the second phase, a hydride of the alloy was nucleated at the film/substrate interface as a result of hydrogenation of the solid solution, and a mixture layer of the hydride and solution was formed. With proceeding hydrogenation, the thickness of the mixture layer increased and the homogenous hydride layer was afterwards formed at the film/substrate interface. As a result of further hydrogenation, the Mg-Ni alloy layer was completely hydrogenated. After the alloy layer was completely hydrogenated, the hydrogenation of Pd was terminated.
|
|
| 10. |
- Yoshida, H., et al.
(författare)
-
Sex differences in effects of valsartan administration on cardiovascular outcomes in hypertensive patients: findings from the Jikei Heart Study
- 2010
-
Ingår i: Journal of Hypertension. - 0263-6352. ; 28:6, s. 1150-1157
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: The randomized Jikei Heart Study has demonstrated that the addition of valsartan to conventional treatments prevents more cardiovascular events in Japanese patients with hypertension. This substudy analyses the sex difference in cardiovascular disease risk reduction in the Jikei Heart Study. METHODS: Treatment effects were evaluated by sex (1038 women and 2043 men) as hazard ratios with 95% confidence intervals (CIs) using Cox regression models adjusted for age, BMI, smoking, dyslipidemia, diabetes, antihypertensives, and statin use at baseline. RESULTS: Women were older, had higher SBP, total and low-density lipoprotein cholesterol but were less frequently smokers or diabetics, and had a lower DBP and incidence of coronary artery disease. A greater incidence of primary endpoint, a composite of cardiovascular events, occurred in men versus women [hazard ratio 1.37 (95% CI 1.02-1.85)]. Men in the valsartan group had a significant reduction in the primary endpoint [hazard ratio 0.6 (95% CI 0.44-0.82), P = 0.001], whereas a nonsignificant effect was found in women [hazard ratio 0.64 (95% CI 0.39-1.06), P = 0.075]. However, statistical heterogeneity of this valsartan effect was not found between sexes, and women of at least 55 years of age, mostly after menopause, in the valsartan group showed a significant risk reduction for the primary endpoint [hazard ratio 0.60 (95% CI 0.36-0.99)]. CONCLUSION: The valsartan effect was significant in men and in elderly women but consistent in both sexes. A potential cardiovascular protection by valsartan therapy might be attributed to the cardiovascular risk level but not to the sex difference.
|
|
