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1.
  • Correa, D. F., et al. (author)
  • Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates
  • 2023
  • In: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 32:1, s. 49-69
  • Journal article (peer-reviewed)abstract
    • Aim To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis). Time period Tree-inventory plots established between 1934 and 2019. Major taxa studied Trees with a diameter at breast height (DBH) >= 9.55 cm. Location Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield. Methods We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes. Results Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests. Main conclusions The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types.
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2.
  • Herrick, A. L., et al. (author)
  • Patterns and predictors of skin score change in early diffuse systemic sclerosis from the European Scleroderma Observational Study
  • 2018
  • In: Annals of the Rheumatic Diseases. - : BMJ. - 0003-4967 .- 1468-2060. ; 77:4, s. 563-570
  • Journal article (peer-reviewed)abstract
    • Objectives Our aim was to use the opportunity provided by the European Scleroderma Observational Study to (1) identify and describe those patients with early diffuse cutaneous systemic sclerosis (dcSSc) with progressive skin thickness, and (2) derive prediction models for progression over 12 months, to inform future randomised controlled trials (RCTs). Methods The modified Rodnan skin score (mRSS) was recorded every 3 months in 326 patients. 'Progressors' were defined as those experiencing a 5-unit and 25% increase in mRSS score over 12 months (±3 months). Logistic models were fitted to predict progression and, using receiver operating characteristic (ROC) curves, were compared on the basis of the area under curve (AUC), accuracy and positive predictive value (PPV). Results 66 patients (22.5%) progressed, 227 (77.5%) did not (33 could not have their status assessed due to insufficient data). Progressors had shorter disease duration (median 8.1 vs 12.6 months, P=0.001) and lower mRSS (median 19 vs 21 units, P=0.030) than non-progressors. Skin score was highest, and peaked earliest, in the anti-RNA polymerase III (Pol3+) subgroup (n=50). A first predictive model (including mRSS, duration of skin thickening and their interaction) had an accuracy of 60.9%, AUC of 0.666 and PPV of 33.8%. By adding a variable for Pol3 positivity, the model reached an accuracy of 71%, AUC of 0.711 and PPV of 41%. Conclusions Two prediction models for progressive skin thickening were derived, for use both in clinical practice and for cohort enrichment in RCTs. These models will inform recruitment into the many clinical trials of dcSSc projected for the coming years. Trial registration number NCT02339441. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
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3.
  • Householder, John Ethan, et al. (author)
  • One sixth of Amazonian tree diversity is dependent on river floodplains
  • 2024
  • In: NATURE ECOLOGY & EVOLUTION. - 2397-334X.
  • Journal article (peer-reviewed)abstract
    • Amazonia's floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and how this may differ from surrounding forest types is still far too limited, particularly as changing inundation regimes begin to reshape floodplain tree communities and the critical ecosystem functions they underpin. Here we address this gap by taking a spatially explicit look at Amazonia-wide patterns of tree-species turnover and ecological specialization of the region's floodplain forests. We show that the majority of Amazonian tree species can inhabit floodplains, and about a sixth of Amazonian tree diversity is ecologically specialized on floodplains. The degree of specialization in floodplain communities is driven by regional flood patterns, with the most compositionally differentiated floodplain forests located centrally within the fluvial network and contingent on the most extraordinary flood magnitudes regionally. Our results provide a spatially explicit view of ecological specialization of floodplain forest communities and expose the need for whole-basin hydrological integrity to protect the Amazon's tree diversity and its function.
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4.
  • Luize, Bruno Garcia, et al. (author)
  • Geography and ecology shape the phylogenetic composition of Amazonian tree communities
  • 2024
  • In: JOURNAL OF BIOGEOGRAPHY. - 0305-0270 .- 1365-2699.
  • Journal article (peer-reviewed)abstract
    • Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and v & aacute;rzea forest types, the phylogenetic composition varies by geographic region, but the igap & oacute; and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R-2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R-2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions.
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5.
  • ter Steege, Hans, et al. (author)
  • Mapping density, diversity and species-richness of the Amazon tree flora
  • 2023
  • In: COMMUNICATIONS BIOLOGY. - 2399-3642. ; 6:1
  • Journal article (peer-reviewed)abstract
    • Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution. A study mapping the tree species richness in Amazonian forests shows that soil type exerts a strong effect on species richness, probably caused by the areas of these forest types. Cumulative water deficit, tree density and temperature seasonality affect species richness at a regional scale.
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6.
  • Armbrecht, G., et al. (author)
  • Vertebral Scheuermann's disease in Europe: prevalence, geographic variation and radiological correlates in men and women aged 50 and over
  • 2015
  • In: Osteoporosis International. - : Springer Science and Business Media LLC. - 1433-2965 .- 0937-941X. ; 26:10, s. 2509-2519
  • Journal article (peer-reviewed)abstract
    • The Summary In 27 centres across Europe, the prevalence of deforming spinal Scheuermann's disease in age-stratified population-based samples of over 10,000 men and women aged 50+ averaged 8 % in each sex, but was highly variable between centres. Low DXA BMD was un-associated with Scheuermann's, helping the differential diagnosis from osteoporosis. Introduction This study aims to assess the prevalence of Scheuermann's disease of the spine across Europe in men and women over 50 years of age, to quantitate its association with bone mineral density (BMD) and to assess its role as a confounder for the radiographic diagnosis of osteoporotic fracture. Methods In 27 centres participating in the population-based European Vertebral Osteoporosis Study (EVOS), standardised lateral radiographs of the lumbar and of the thoracic spine from T4 to L4 were assessed in all those of adequate quality. The presence of Scheuermann's disease, a confounder for prevalent fracture in later life, was defined by the presence of at least one Schmorl's node or irregular endplate together with kyphosis (sagittal Cobb angle > 40A degrees between T4 and T12) or a wedged-shaped vertebral body. Alternatively, the (rare) Edgren-Vaino sign was taken as diagnostic. The 6-point-per-vertebral-body (13 vertebrae) method was used to assess osteoporotic vertebral shape and fracture caseness. DXA BMD of the L2-L4 and femoral neck regions was measured in subsets. We also assessed the presence of Scheuermann's by alternative published algorithms when these used the radiographic signs we assessed. Results Vertebral radiographic images from 4486 men and 5655 women passed all quality checks. Prevalence of Scheuermann's varied considerably between centres, and based on random effect modelling, the overall European prevalence using our method was 8 % with no significant difference between sexes. The highest prevalences were seen in Germany, Sweden, the UK and France and low prevalences were seen in Hungary, Poland and Slovakia. Centre-level prevalences in men and women were highly correlated. Scheuermann's was not associated with BMD of the spine or hip. Conclusions Since most of the variation in population impact of Scheuermann's was unaccounted for by the radiological and anthropometric data, the search for new genetic and environmental determinants of this disease is encouraged.
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7.
  • J L Sussman, M Harel, M L Raves, K Giles, R B G Ravelli, L G M Peng, G J Kleywegt, D M Quinn, H K Nair, and I Silman (author)
  • Studies on the 3-D structure of Torpedo Acetylcholinesterase
  • 1996
  • In: 1996 U.S. Army Medical Defense Bioscience Review. - : U.S. Army Medical Research Institute of Chemical Defense, Baltimore, MD. ; , s. 13-22
  • Book chapter (peer-reviewed)
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8.
  • Rutter, M. K., et al. (author)
  • Epidemiological evidence against a role for C-reactive protein causing leptin resistance
  • 2013
  • In: European Journal of Endocrinology. - 1479-683X. ; 168:1, s. 101-106
  • Journal article (peer-reviewed)abstract
    • Objective: It has been suggested that elevated levels of C-reactive protein (CRP) might interfere with leptin signalling and contribute to leptin resistance. Our aim was to assess whether plasma levels of CRP influence leptin resistance in humans, and our hypothesis was that CRP levels would modify the cross-sectional relationships between leptin and measures of adiposity. Design and methods: We assessed four measures of adiposity: BMI, waist circumference, fat mass and body fat (%) in 2113 British Regional Heart Study (BRHS) men (mean (S.D.) age 69 (5) years), with replication in 760 (age 69 (6) years) European Male Ageing Study (EMAS) subjects. Results: In BRHS subjects, leptin correlated with CRP (Spearman's r=0.22, P<0.0001). Leptin and CRP correlated with all four measures of adiposity (r value range: 0.22-0.57, all P<0.0001). Age-adjusted mean levels for adiposity measures increased in relation to leptin levels, but CRP level did not consistently influence the beta-coefficients of the regression lines in a CRP-stratified analysis. In BRHS subjects, the BMI vs leptin relationship demonstrated a weak statistical interaction with CRP (P=0.04). We observed no similar interaction in EMAS subjects and no significant interactions with other measures of adiposity in BRHS or EMAS cohorts. Conclusion: We have shown that plasma CRP has little influence on the relationship between measures of adiposity and serum leptin levels in these middle-aged and elderly male European cohorts. This study provides epidemiological evidence against CRP having a significant role in causing leptin resistance. European Journal of Endocrinology 168 101-106
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  • Kaptoge, S., et al. (author)
  • Whom to treat? The contribution of vertebral X-rays to risk-based algorithms for fracture prediction. Results from the European Prospective Osteoporosis Study
  • 2006
  • In: Osteoporosis International. - : Springer Science and Business Media LLC. - 1433-2965 .- 0937-941X. ; 17:9, s. 1369-1381
  • Journal article (peer-reviewed)abstract
    • Introduction: Vertebral fracture is a strong risk factor for future spine and hip fractures; yet recent data suggest that only 5-20% of subjects with a spine fracture are identified in primary care. We aimed to develop easily applicable algorithms predicting a high risk of future spine fracture in men and women over 50 years of age. Methods: Data was analysed from 5,561 men and women aged 50+ years participating in the European Prospective Osteoporosis Study (EPOS). Lateral thoracic and lumbar spine radiographs were taken at baseline and at an average of 3.8 years later. These were evaluated by an experienced radiologist. The risk of a new (incident) vertebral fracture was modelled as a function of age, number of prevalent vertebral fractures, height loss, sex and other fracture history reported by the subject, including limb fractures occurring between X-rays. Receiver Operating Characteristic (ROC) curves were used to compare the predictive ability of models. Results: In a negative binomial regression model without baseline X-ray data, the risk of incident vertebral fracture significantly increased with age [RR 1.74, 95% CI (1.44, 2.10) per decade], height loss [1.08 (1.04, 1.12) per cm decrease], female sex [1.48 (1.05, 2.09)], and recalled fracture history; [1.65 (1.15, 2.38) to 3.03 (1.66, 5.54)] according to fracture site. Baseline radiological assessment of prevalent vertebral fracture significantly improved the areas subtended by ROC curves from 0.71 (0.67, 0.74) to 0.74 (0.70, 0.77) P=0.013 for predicting 1+ incident fracture; and from 0.74 (0.67, 0.81) to 0.83 (0.76, 0.90) P=0.001 for 2+ incident fractures. Age, sex and height loss remained independently predictive. The relative risk of a new vertebral fracture increased with the number of prevalent vertebral fractures present from 3.08 (2.10, 4.52) for 1 fracture to 9.36 (5.72, 15.32) for 3+. At a specificity of 90%, the model including X-ray data improved the sensitivity for predicting 2+ and 1+ incident fractures by 6 and 4 fold respectively compared with random guessing. At 75% specificity the improvements were 3.2 and 2.4 fold respectively. With the modelling restricted to the subjects who had BMD measurements (n=2,409), the AUC for predicting 1+ vs. 0 incident vertebral fractures improved from 0.72 (0.66, 0.79) to 0.76 (0.71, 0.82) upon adding femoral neck BMD (P=0.010). Conclusion: We conclude that for those with existing vertebral fractures, an accurately read spine X-ray will form a central component in future algorithms for targeting treatment, especially to the most vulnerable. The sensitivity of this approach to identifying vertebral fracture cases requiring anti-osteoporosis treatment, even when X-rays are ordered highly selectively, exceeds by a large margin the current standard of practice as recorded anywhere in the world.
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11.
  • Cockerill, W, et al. (author)
  • Health-related quality of life and radiographic vertebral fracture
  • 2004
  • In: Osteoporosis International. - : Springer Science and Business Media LLC. - 1433-2965 .- 0937-941X. ; 15:2, s. 113-119
  • Journal article (peer-reviewed)abstract
    • Background: Vertebral fractures are associated with back pain and disability; however, relatively little is known about the impact of radiographic vertebral fractures on quality of life in population samples. The aim of this study was to determine the impact of a recent radiographic vertebral fracture on health-related quality of life (HRQoL). Methods: Men and women aged 50 years and over were recruited from population registers in 12 European centers. Subjects completed an interviewer-administered questionnaire and had lateral spine radiographs performed. Subjects in these centers were followed prospectively and had repeat spinal radiographs performed a mean of 3.8 years later. Prevalent deformities were defined using established morphometric criteria, and incident vertebral fractures by both morphometric criteria and qualitative assessment. For each incident fracture case, three controls matched for age, gender, and center were selected: one with a prevalent deformity (at baseline) and two without prevalent deformities. All subjects were interviewed or completed a postal questionnaire instrument which included Short Form 12 (SF-12), the EQ-5D (former EuroQol), and the quality of life questionnaire of the International Osteoporosis Foundation (QUALEFFO). The median time from the second spinal radiograph until the quality of life survey was 1.9 years. Comparison between cases and their matched controls was undertaken using the signed rank test. Results: 73 subjects with incident vertebral fracture (cases), mean age 64.8 years (of whom 23 had a baseline deformity), and 196 controls, mean age 63.9 years (of whom 60 had a baseline deformity), were studied. There were strong correlations between the domain scores for each of the three instruments. There was no statistically significant difference in any of the domain scores between cases and those controls with a prevalent deformity. However, compared with the controls without a prevalent deformity the cases had significantly impaired quality of life as determined using the total QUALEFFO score (38.2 vs 33.7), the physical component score of the SF-12 (39.9 vs 43.7) and the health status score of the EQ-5D (62.3 vs 69.9). When the analysis was repeated after stratification of the cases by baseline deformity status (i.e., cases with and without a prevalent deformity at baseline), cases with a prevalent deformity had impaired quality of life compared with their matched controls, both with and without a prevalent deformity. In contrast there was no significant difference in quality of life among the cases without a prevalent deformity and either control group. Conclusion: In this population-based study a recent vertebral fracture was associated with impairment in quality of life, though this was mainly among those who had sustained a previous vertebral deformity.
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  • Halbritter, Aud H., et al. (author)
  • Plant trait and vegetation data along a 1314 m elevation gradient with fire history in Puna grasslands, Perú
  • 2024
  • In: SCIENTIFIC DATA. - 2052-4463. ; 11:1
  • Journal article (peer-reviewed)abstract
    • Alpine grassland vegetation supports globally important biodiversity and ecosystems that are increasingly threatened by climate warming and other environmental changes. Trait-based approaches can support understanding of vegetation responses to global change drivers and consequences for ecosystem functioning. In six sites along a 1314 m elevational gradient in Puna grasslands in the Peruvian Andes, we collected datasets on vascular plant composition, plant functional traits, biomass, ecosystem fluxes, and climate data over three years. The data were collected in the wet and dry season and from plots with different fire histories. We selected traits associated with plant resource use, growth, and life history strategies (leaf area, leaf dry/wet mass, leaf thickness, specific leaf area, leaf dry matter content, leaf C, N, P content, C and N isotopes). The trait dataset contains 3,665 plant records from 145 taxa, 54,036 trait measurements (increasing the trait data coverage of the regional flora by 420%) covering 14 traits and 121 plant taxa (ca. 40% of which have no previous publicly available trait data) across 33 families.
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14.
  • Ismail, AA, et al. (author)
  • Incidence of limb fracture across Europe: Results from the European Prospective Osteoporosis Study (EPOS)
  • 2002
  • In: Osteoporosis International. - : Springer Science and Business Media LLC. - 1433-2965 .- 0937-941X. ; 13:7, s. 565-571
  • Journal article (peer-reviewed)abstract
    • The aim of this population-based prospective study was to determine the incidence of limb fracture by site and gender in different regions of Europe. Men and women aged 50-79 years were recruited from population registers in 31 European centers. Subjects were invited to attend for an interviewer-administered questionnaire and lateral spinal radiographs. Subjects were subsequently followed up using an annual postal questionnaire which included questions concerning the occurrence of new fractures. Self-reported fractures were confirmed where possible by radiograph, attending physician or subject interview. There were 6451 men and 6936 women followed for a median of 3.0 years. During this time there were 140 incident limb fractures in men and 391 in women. The age-adjusted incidence of any limb fracture was 7,3/1000 person-years [pyrs] in men and 19 per 1000 pyrs in women, equivalent to a 2,5 times excess in women. Among women, the incidence of hip, humerus and distal forearm fracture, though not 'other' limb fracture, increased with age, while in men only the incidence of hip and humerus fracture increased with age. Among women, there was evidence of significant variation in the occurrence of hip, distal forearm and humerus fractures across Europe, with incidence rates higher in Scandinavia than in other European regions. though for distal forearm fracture the incidence in east Europe was similar to that observed in Scandinavia. Among men, there was no evidence of significant geographic variation in the occurrence of these fractures. This is the first large population-based study to characterize the incidence of limb fracture in men and women over 50 years of age across Europe. There are substantial differences in the descriptive epidemiology of limb fracture by region and gender.
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  • Macfarlane, G. J., et al. (author)
  • Investigating the determinants of international differences in the prevalence of chronic widespread pain: evidence from the European Male Ageing Study
  • 2009
  • In: Annals of the Rheumatic Diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 68:5, s. 690-695
  • Journal article (peer-reviewed)abstract
    • Objectives: To determine whether among middle-aged and elderly men there is evidence of international differences in the prevalence of chronic widespread pain (CWP) and whether any such differences could be explained by psychological, psychosocial factors or differences in physical health status. Methods: The European Male Ageing Study (EMAS) sampled from population registers in cities ( centres) of eight European countries. Each centre recruited an age-stratified sample of men aged 40-79 years. Information on pain was collected by questionnaire and subjects were classified according to whether they satisfied the American College of Rheumatology definition of CWP. Information was collected on social status, mental health, recent life events and co-morbidities. Results: Across all centres 3963 subjects completed a study questionnaire, with participation rates ranging from 24% in Hungary to 72% in Estonia. There were significant differences in prevalence: between 5% and 7% in centres in Italy, England, Belgium and Sweden, 9-15% in centres in Spain, Poland and Hungary and 15% in Estonia. There were strong relationships between poor mental health, adverse recent life events, co-morbidities and CWP. Adjustment for these factors explained between half and all of the excess risk in the eastern European centres: the excess risk in Poland was explained ( odds ratio ( OR) 1.1, 95% CI 0.9 to 1.2) but there remained excess risk in Hungary ( OR 1.6, 95% CI 1.4 to 1.8) and Estonia ( OR 2.6, 95% CI 2.2 to 2.9). Conclusions: This study is the first directly to compare the occurrence of CWP internationally. There is an excess prevalence in countries of eastern Europe and this excess is associated with adverse psychosocial factors as well as poorer psychological and physical health.
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  • Silman, A. J., et al. (author)
  • International variation in distribution of ASA class in patients undergoing total hip arthroplasty and its influence on mortality: data from an international consortium of arthroplasty registries
  • 2021
  • In: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3674 .- 1745-3682. ; 92:3, s. 304-310
  • Journal article (peer-reviewed)abstract
    • Background and purpose - A challenge comparing outcomes from total hip arthroplasty between countries is variation in preoperative characteristics, particularly comorbidity. Therefore, we investigated between-country variation in comorbidity in patients based on ASA class distribution, and determined any variation of ASA class to mortality risk between countries. Patients and methods - All arthroplasty registries collecting ASA class and mortality data in patients with elective primary THAs performed 2012-2016 were identified. Survival analyses of the influence of ASA class on 1-year mortality were performed by individual registries, followed by meta-analysis of aggregated data. Results - 6 national registries and 1 US healthcare organization registry with 418,916 THAs were included. There was substantial variation in the proportion of ASA class III/IV, ranging from 14% in the Netherlands to 39% in Finland. Overall, 1-year mortality was 0.93% (95% CI 0.87-1.01) and increased from 0.2% in ASA class I to 8.9% in class IV. The association between ASA class and mortality measured by hazard ratios (HR) was strong in all registries even after adjustment for age and sex, which reduced them by half in all registries. Combined adjusted HRs were 2.0, 6.1, and 22 for ASA class II-IV vs. I, respectively. Associations were moderately heterogeneous across registries. Interpretation - We observed large variation in ASA class distribution between registries, possibly explained by differences in background morbidity and/or international variation in access to surgery. The similar, strong mortality trends by ASA class between countries enhance the relevance of its use as an indicator of comorbidity in international registry studies.
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19.
  • Vanderschueren, D., et al. (author)
  • Gonadal sex steroid status and bone health in middle-aged and elderly European men
  • 2010
  • In: Osteoporosis International. - : Springer Science and Business Media LLC. - 1433-2965 .- 0937-941X. ; 21:8, s. 1331-1339
  • Journal article (peer-reviewed)abstract
    • The influence of sex steroids on calcaneal quantitative ultrasound (QUS) parameters was assessed in a population sample of middle-aged and elderly European men. Higher free and total E-2 though not testosterone, were independently associated with higher QUS parameters. The aim of this study was to investigate the association between QUS parameters and sex steroids in middle-aged and elderly European men. Three thousand one hundred forty-one men aged between 40 and 79 years were recruited from eight European centres for participation in a study of male ageing: the European Male Ageing Study. Subjects were invited by letter to attend for an interviewer-administered questionnaire, blood sample and QUS of the calcaneus (Hologic-SAHARA). Blood was assessed for sex steroids including oestradiol (E-2), testosterone (T), free and bio-available E-2 and T and sex hormone binding globulin (SHBG). Serum total T was not associated with any of the QUS parameters. Free T and both free and total E-2 were positively related to all QUS readings, while SHBG concentrations were negatively associated. These relationships were observed in both older and younger (< 60 years) men. In a multivariate model, after adjustment for age, centre, height, weight, physical activity levels and smoking, free E-2 and SHBG, though not free T, remained independently associated with the QUS parameters. After further adjustment for IGF-1, however, the association with SHBG became non-significant. Higher free and total E-2 are associated with bone health not only among the elderly but also middle-aged European men.
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20.
  • Ward, K. A., et al. (author)
  • Influence of age and sex steroids on bone density and geometry in middle-aged and elderly European men
  • 2011
  • In: Osteoporosis International. - : Springer Science and Business Media LLC. - 1433-2965 .- 0937-941X. ; 22:5, s. 1513-1523
  • Journal article (peer-reviewed)abstract
    • The influence of age and sex steroids on bone density and geometry of the radius was examined in two European Caucasian populations. Age-related change in bone density and geometry was observed. In older men, bioavailable oestradiol may play a role in the maintenance of cortical and trabecular bone mineral density (BMD). To examine the effect of age and sex steroids on bone density and geometry of the radius in two European Caucasian populations. European Caucasian men aged 40-79 years were recruited from population registers in two centres: Manchester (UK) and Leuven (Belgium), for participation in the European Male Ageing Study. Total testosterone (T) and oestradiol (E-2) were measured by mass spectrometry and the free and bioavailable fractions calculated. Peripheral quantitative computed tomography was used to scan the radius at distal (4%) and midshaft (50%) sites. Three hundred thirty-nine men from Manchester and 389 from Leuven, mean ages 60.2 and 60.0 years, respectively, participated. At the 50% radius site, there was a significant decrease with age in cortical BMD, bone mineral content (BMC), cortical thickness, and muscle area, whilst medullary area increased. At the 4% radius site, trabecular and total volumetric BMD declined with age. Increasing bioavailable E-2 (bioE(2)) was associated with increased cortical BMD (50% radius site) and trabecular BMD (4% radius site) in Leuven, but not Manchester, men. This effect was predominantly in those aged 60 years and over. In older Leuven men, bioavailable testosterone (Bio T) was linked with increased cortical BMC, muscle area and SSI (50% radius site) and total area (4% radius site). There is age-related change in bone density and geometry at the midshaft radius in middle-aged and elderly European men. In older men bioE(2) may maintain cortical and trabecular BMD. BioT may influence bone health through associations with muscle mass and bone area.
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  • Cook, Michael J., et al. (author)
  • Frailty and bone health in European men
  • 2017
  • In: Age and Ageing. - : Oxford University Press (OUP). - 0002-0729 .- 1468-2834. ; 46:4, s. 635-641
  • Journal article (peer-reviewed)abstract
    • Background: frailty is associated with an increased risk of fragility fractures. Less is known, however, about the association between frailty and bone health.Methods: men aged 40-79 years were recruited from population registers in eight European centres for participation in the European Male Aging Study. Subjects completed a comprehensive assessment which included quantitative ultrasound (QUS) scan of the heel (Hologic-SAHARA) and in two centres, dual-energy bone densitometry (dual-energy x-ray absorptiometry, DXA). Frailty was defined based on an adaptation of Fried's phenotype criteria and a frailty index (FI) was constructed. The association between frailty and the QUS and DXA parameters was determined using linear regression, with adjustments for age, body mass index and centre.Results: in total, 3,231 subjects contributed data to the analysis. Using the Fried categorisation of frailty, pre-frail and frail men had significantly lower speed of sound (SOS), broadband ultrasound attenuation (BUA) and quantitative ultrasound index (QUI) compared to robust men (P< 0.05). Similar results were seen using the FI after categorisation into 'high', 'medium' and 'low' levels of frailty. Using the Fried categorisation, frail men had lower femoral neck bone mineral density (BMD) compared to robust men (P < 0.05), but not lower lumbar spine BMD. Using the FI categorisation, a 'high' level of frailty (FI > 0.35) was associated with lower lumbar spine BMD (P < 0.05) when compared to those with low (FI < 0.2), but not lower femoral neck BMD. When analysed as a continuous variable, higher FI was linked with lower SOS, BUA and QUI (P < 0.05).Conclusions: optimisation of bone health as well as prevention of falls should be considered as strategies to reduce fractures in frail older people.
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23.
  • Harel, M, et al. (author)
  • Crystal structure of an acetylcholinesterase-fasciculin complex: interaction of a three-fingered toxin from snake venom with its target.
  • 1995
  • In: Structure. - 0969-2126. ; 3:12, s. 1355-66
  • Journal article (peer-reviewed)abstract
    • BACKGROUND: Fasciculin (FAS), a 61-residue polypeptide purified from mamba venom, is a three-fingered toxin which is a powerful reversible inhibitor of acetylcholinesterase (AChE). Solution of the three-dimensional structure of the AChE/FAS complex would provide the first structure of a three-fingered toxin complexed with its target. RESULTS: The structure of a complex between Torpedo californica AChE and fasciculin-II (FAS-II), from the venom of the green mamba (Dendroaspis angusticeps) was solved by molecular replacement techniques, and refined at 3.0 A resolution to an R-factor of 0.231. The structure reveals a stoichiometric complex with one FAS molecule bound to each AChE subunit. The AChE and FAS conformations in the complex are very similar to those in their isolated structures. FAS is bound at the 'peripheral' anionic site of AChE, sealing the narrow gorge leading to the active site, with the dipole moments of the two molecules roughly aligned. The high affinity of FAS for AChE is due to a remarkable surface complementarity, involving a large contact area (approximately 2000 A2) and many residues either unique to FAS or rare in other three-fingered toxins. The first loop, or finger, of FAS reaches down the outer surface of the thin aspect of the gorge. The second loop inserts into the gorge, with an unusual stacking interaction between Met33 in FAS and Trp279 in AChE. The third loop points away from the gorge, but the C-terminal residue makes contact with the enzyme. CONCLUSIONS: Two conserved aromatic residues in the AChE peripheral anionic site make important contacts with FAS. The absence of these residues from chicken and insect AChEs and from butyrylcholinesterase explains the very large reduction in the affinity of these enzymes for FAS. Several basic residues in FAS make important contacts with AChE. The complementarity between FAS and AChE is unusual, inasmuch as it involves a number of charged residues, but lacks any intermolecular salt linkages.
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24.
  • Huaraca Huasco, Walter, et al. (author)
  • Fine root dynamics across pantropical rainforest ecosystems
  • 2021
  • In: Global Change Biology. - : John Wiley & Sons. - 1354-1013 .- 1365-2486. ; 27:15, s. 3657-3680
  • Journal article (peer-reviewed)abstract
    • Fine roots constitute a significant component of the net primary productivity (NPP) of forest ecosystems but are much less studied than aboveground NPP. Comparisons across sites and regions are also hampered by inconsistent methodologies, especially in tropical areas. Here, we present a novel dataset of fine root biomass, productivity, residence time, and allocation in tropical old-growth rainforest sites worldwide, measured using consistent methods, and examine how these variables are related to consistently determined soil and climatic characteristics. Our pantropical dataset spans intensive monitoring plots in lowland (wet, semi-deciduous, and deciduous) and montane tropical forests in South America, Africa, and Southeast Asia (n = 47). Large spatial variation in fine root dynamics was observed across montane and lowland forest types. In lowland forests, we found a strong positive linear relationship between fine root productivity and sand content, this relationship was even stronger when we considered the fractional allocation of total NPP to fine roots, demonstrating that understanding allocation adds explanatory power to understanding fine root productivity and total NPP. Fine root residence time was a function of multiple factors: soil sand content, soil pH, and maximum water deficit, with longest residence times in acidic, sandy, and water-stressed soils. In tropical montane forests, on the other hand, a different set of relationships prevailed, highlighting the very different nature of montane and lowland forest biomes. Root productivity was a strong positive linear function of mean annual temperature, root residence time was a strong positive function of soil nitrogen content in montane forests, and lastly decreasing soil P content increased allocation of productivity to fine roots. In contrast to the lowlands, environmental conditions were a better predictor for fine root productivity than for fractional allocation of total NPP to fine roots, suggesting that root productivity is a particularly strong driver of NPP allocation in tropical mountain regions.
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25.
  • Lee, David M, et al. (author)
  • Cohort Profile: The European Male Ageing Study.
  • 2013
  • In: International Journal of Epidemiology. - : Oxford University Press (OUP). - 1464-3685 .- 0300-5771. ; 42:2, s. 391-401
  • Journal article (peer-reviewed)abstract
    • The European Male Ageing Study (EMAS) was designed to examine the hypothesis that inter-individual and regional variability in symptomatic dysfunctions, alterations in body composition and health outcomes in ageing men can be explained by different rates of decline in anabolic hormones, the most important of which being testosterone. Between 2003 and 2005, 3369 community-dwelling men, aged between 40 and 79 years, were recruited from population-based registers in eight European centres to participate in the baseline survey, with follow-up investigations performed a median of 4.3 years later. Largely, identical questionnaire instruments and clinical investigations were used in both phases to capture contemporaneous data on general health (including cardiovascular diseases and chronic conditions), physical and cognitive functioning, mental health, sexual function, quality of life, bone health, chronic pain, disease biomarkers, hormones (sex hormones and metabolic hormones) and genetic polymorphisms. EMAS actively encourages new collaborations, data sharing for validation studies and participation in genetic study consortia. Potential collaborators should contact the principal investigator (F.C.W.W.) in the first instance.
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26.
  • Lee, David M., et al. (author)
  • Endogenous hormones, androgen receptor CAG repeat length and fluid cognition in middle-aged and older men: results from the European Male Ageing Study
  • 2010
  • In: European Journal of Endocrinology. - 1479-683X. ; 162:6, s. 1155-1164
  • Journal article (peer-reviewed)abstract
    • Objective: Data remain divergent regarding the activational effects of endogenous hormones on adult cognitive function. We examined the association between cognition, hormones and androgen receptor (AR) CAG repeat length in a large cohort of men. Design: Community-based, cross-sectional study of 3369 men aged 40-79 years. Methods: Cognition tests were the Rey-Osterrieth Complex Figure, Camden Topographical Recognition Memory and Digit-Symbol Substitution. A fluid cognition (FC) z-score was computed from the individual tests. Testosterone, oestradiol (OE2) and 5 alpha-dihydrotestosterone were measured by gas chromatography-mass spectrometry; DHEAS, LH, FSH and sex hormone-binding globulin (SHBG) by electrochemiluminescence. Free testosterone and OE2 were calculated from total hormone, SHBG and albumin. CAG repeat lengths were assayed by PCR genotyping. Results: Total testosterone and free testosterone were associated with higher FC z-scores, LH and FSH with lower FC z-scores in age-adjusted linear regressions. After adjusting for health, lifestyle and centre, a modest association was only observed between DHEAS and a lower FC z-score (beta=-0.011, P=0.02), although this was driven by subjects with DHEAS levels > 10 mu mol/l. Locally weighted plots revealed no threshold effects between hormones and FC. There was no association between CAG repeat length and FC z-score after adjustment for age and centre (beta=-0.007, P=0.06), nor any interaction effect between CAG repeat length and hormones. Conclusion: Our results suggest that endogenous hormones are not associated with a vision-based measure of FC among healthy, community-dwelling men. Further studies are warranted to determine whether 'high' DHEAS levels are associated with poorer performance on a broader range of neuropsychological tests.
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27.
  • Lee, David M., et al. (author)
  • The European Male Ageing Study (EMAS): design, methods and recruitment
  • 2009
  • In: International Journal of Andrology. - : Wiley. - 0105-6263 .- 1365-2605. ; 32:1, s. 11-24
  • Journal article (peer-reviewed)abstract
    • Life expectancy is increasing in most developed countries, in part due to improved socioeconomic conditions and in part to advances in healthcare. It is widely acknowledged that the promotion of healthy ageing by delaying, minimizing or preventing disabilities or diseases is one of the most important public health objectives in this century. In contrast to the menopausal transition in females, we know relatively little about the contribution of androgens and anabolic hormones to the quality of ageing in men. The European Male Ageing Study (EMAS) is a multicentre prospective cohort designed to examine the prevalence, incidence and geographical distribution of gender-specific and general symptoms of ageing in men, including their endocrine, genetic and psychosocial predictors. Men aged 40-79 years were recruited from eight European centres: Florence (Italy), Leuven (Belgium), Lodz (Poland), Malmo (Sweden), Manchester (UK), Santiago de Compostela (Spain), Szeged (Hungary) and Tartu (Estonia). Subjects were recruited from population registers and those who agreed to take part completed a detailed questionnaire including aspects of personal and medical history, lifestyle factors and sexual function. Objective measures of body size, cognition, vision, skeletal health and neuromuscular function were obtained. Blood and DNA specimens were collected for a range of biochemical and genetic analyses. After an average of 4 years, it is planned to resurvey the participants with similar assessments. A total of 3369 men with a mean age of 60 +/- 11 years were recruited. The mean centre response rate was 43%, and highest in those aged 50-59 years. Those who participated were marginally younger than those who were invited but declined to participate (60.0 vs. 61.1 years). Participants left education slightly later than a sample of non-participants, though there were no consistent differences in levels of general health, physical activity, or smoking. EMAS will provide new population-based data concerning the main features that characterize ageing in men and its critical determinants, particularly with reference to age-related changes in hormone levels. Such information is an important prerequisite to develop effective strategies to reduce age-related disabilities and optimise health and well-being into old-age.
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28.
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29.
  • MacFarlane, G.J., et al. (author)
  • Evaluation of work-related psychosocial factors and regional musculoskeletal pain : results from a EULAR Task Force
  • 2009
  • In: Annals of the Rheumatic Diseases. - London : BMJ Publishing Group Ltd. - 0003-4967 .- 1468-2060. ; 68:6, s. 885-891
  • Journal article (peer-reviewed)abstract
    • Objectives: To establish whether review articles provide consistent conclusions on associations between workplace psychosocial factors and musculoskeletal pain and, if differences exist, to explore whether this is related to the methods used.Methods: Reviews, reported up to February 2007, that included consideration of workplace psychosocial factors and upper limb, back or knee pain were identified through searches of multiple databases. The specific work-related psychosocial factors considered were job demands, support, job autonomy and job satisfaction. The conclusions of each review on one or more of the psychosocial/musculoskeletal pain associations were extracted.Results: 15 review articles were identified that considered one or more of the regional pain syndromes included in the study. For back pain, the most consistent conclusions (four reviews positive out of six) were with high job demands and low job satisfaction. The studies of upper limb pain were exclusively related to shoulder and/or neck pain, and the most consistent positive conclusions were with high and low job demands (four reviews positive out of six and two reviews positive out of three, respectively). For knee pain, only a single review was identified. For individual reviews of back and upper limb pain, there were marked differences in the number of associations concluded to be positive between reviews.Conclusions: The reasons for reviews coming to different conclusions included that they were often evaluating different bodies of evidence (according to their search criteria, the year when the review was conducted, the role that quality assessment played in whether studies contributed to evidence, and the combination of risk factors addressed in individual studies), but more important was whether the review specified explicit criteria for making conclusions on strength of evidence. These conclusions emphasise the importance of developing standardised methods for conducting such evaluations of existing evidence and the importance of new longitudinal studies for clarifying the temporal relationship between psychosocial factors and musculoskeletal pain in the workplace.
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30.
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31.
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32.
  • Wu, Frederick C. W., et al. (author)
  • Identification of Late-Onset Hypogonadism in Middle-Aged and Elderly Men
  • 2010
  • In: New England Journal of Medicine. - 1533-4406 .- 0028-4793. ; 363:2, s. 123-135
  • Conference paper (peer-reviewed)abstract
    • BACKGROUND The association between aging-related testosterone deficiency and late-onset hypogonadism in men remains a controversial concept. We sought evidence-based criteria for identifying late-onset hypogonadism in the general population on the basis of an association between symptoms and a low testosterone level. METHODS We surveyed a random population sample of 3369 men between the ages of 40 and 79 years at eight European centers. Using questionnaires, we collected data with regard to the subjects' general, sexual, physical, and psychological health. Levels of total testosterone were measured in morning blood samples by mass spectrometry, and free testosterone levels were calculated with the use of Vermeulen's formula. Data were randomly split into separate training and validation sets for confirmatory analyses. RESULTS In the training set, symptoms of poor morning erection, low sexual desire, erectile dysfunction, inability to perform vigorous activity, depression, and fatigue were significantly related to the testosterone level. Increased probabilities of the three sexual symptoms and limited physical vigor were discernible with decreased testosterone levels (ranges, 8.0 to 13.0 nmol per liter [2.3 to 3.7 ng per milliliter] for total testosterone and 160 to 280 pmol per liter [46 to 81 pg per milliliter] for free testosterone). However, only the three sexual symptoms had a syndromic association with decreased testosterone levels. An inverse relationship between an increasing number of sexual symptoms and a decreasing testosterone level was observed. These relationships were independently confirmed in the validation set, in which the strengths of the association between symptoms and low testosterone levels determined the minimum criteria necessary to identify late-onset hypogonadism. CONCLUSIONS Late-onset hypogonadism can be defined by the presence of at least three sexual symptoms associated with a total testosterone level of less than 11 nmol per liter (3.2 ng per milliliter) and a free testosterone level of less than 220 pmol per liter (64 pg per milliliter).
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