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| 4. |
- Lind, Lars, et al.
(författare)
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Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight NCD Risk Factor Collaboration (NCD-RisC)
- 2021
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Ingår i: eLife. - : eLife Sciences Publications Ltd. - 2050-084X. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions.
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| 5. |
- Bixby, H., et al.
(författare)
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Rising rural body-mass index is the main driver of the global obesity epidemic in adults
- 2019
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 569:7755, s. 260-4
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Tidskriftsartikel (refereegranskat)abstract
- Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.
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| 6. |
- Mishra, A, et al.
(författare)
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Diminishing benefits of urban living for children and adolescents' growth and development
- 2023
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 615:7954, s. 874-883
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Tidskriftsartikel (refereegranskat)abstract
- Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified.
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| 14. |
- Taddei, C, et al.
(författare)
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Repositioning of the global epicentre of non-optimal cholesterol
- 2020
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 582:7810, s. 73-
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Tidskriftsartikel (refereegranskat)abstract
- High blood cholesterol is typically considered a feature of wealthy western countries1,2. However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world3 and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health4,5. However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol—which is a marker of cardiovascular risk—changed from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million–4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.
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| 15. |
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| 16. |
- Bentham, James, et al.
(författare)
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A century of trends in adult human height
- 2016
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Ingår i: eLIFE. - 2050-084X. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- Being taller is associated with enhanced longevity, and higher education and earnings. We reanalysed 1472 population-based studies, with measurement of height on more than 18.6 million participants to estimate mean height for people born between 1896 and 1996 in 200 countries. The largest gain in adult height over the past century has occurred in South Korean women and Iranian men, who became 20.2 cm (95% credible interval 17.522.7) and 16.5 cm (13.319.7) taller, respectively. In contrast, there was little change in adult height in some sub-Saharan African countries and in South Asia over the century of analysis. The tallest people over these 100 years are men born in the Netherlands in the last quarter of 20th century, whose average heights surpassed 182.5 cm, and the shortest were women born in Guatemala in 1896 (140.3 cm; 135.8144.8). The height differential between the tallest and shortest populations was 19-20 cm a century ago, and has remained the same for women and increased for men a century later despite substantial changes in the ranking of countries.
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| 17. |
- Bentham, James, et al.
(författare)
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A century of trends in adult human height
- 2016
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Ingår i: eLIFE. - : eLife Sciences Publications Ltd. - 2050-084X. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- Being taller is associated with enhanced longevity, and higher education and earnings. We reanalysed 1472 population-based studies, with measurement of height on more than 18.6 million participants to estimate mean height for people born between 1896 and 1996 in 200 countries. The largest gain in adult height over the past century has occurred in South Korean women and Iranian men, who became 20.2 cm (95% credible interval 17.5–22.7) and 16.5 cm (13.3– 19.7) taller, respectively. In contrast, there was little change in adult height in some sub-Saharan African countries and in South Asia over the century of analysis. The tallest people over these 100 years are men born in the Netherlands in the last quarter of 20th century, whose average heights surpassed 182.5 cm, and the shortest were women born in Guatemala in 1896 (140.3 cm; 135.8– 144.8). The height differential between the tallest and shortest populations was 19-20 cm a century ago, and has remained the same for women and increased for men a century later despite substantial changes in the ranking of countries.
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| 18. |
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| 19. |
- Wang, Z., et al.
(författare)
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Genome-wide association analyses of physical activity and sedentary behavior provide insights into underlying mechanisms and roles in disease prevention
- 2022
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 54:9, s. 1332-1344
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Tidskriftsartikel (refereegranskat)abstract
- Although physical activity and sedentary behavior are moderately heritable, little is known about the mechanisms that influence these traits. Combining data for up to 703,901 individuals from 51 studies in a multi-ancestry meta-analysis of genome-wide association studies yields 99 loci that associate with self-reported moderate-to-vigorous intensity physical activity during leisure time (MVPA), leisure screen time (LST) and/or sedentary behavior at work. Loci associated with LST are enriched for genes whose expression in skeletal muscle is altered by resistance training. A missense variant in ACTN3 makes the alpha-actinin-3 filaments more flexible, resulting in lower maximal force in isolated type IIA muscle fibers, and possibly protection from exercise-induced muscle damage. Finally, Mendelian randomization analyses show that beneficial effects of lower LST and higher MVPA on several risk factors and diseases are mediated or confounded by body mass index (BMI). Our results provide insights into physical activity mechanisms and its role in disease prevention. Multi-ancestry meta-analyses of genome-wide association studies for self-reported physical activity during leisure time, leisure screen time, sedentary commuting and sedentary behavior at work identify 99 loci associated with at least one of these traits.
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| 20. |
- Zhang, X., et al.
(författare)
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Human total, basal and activity energy expenditures are independent of ambient environmental temperature
- 2022
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Ingår i: iScience. - : Elsevier Inc.. - 2589-0042. ; 25:8
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Tidskriftsartikel (refereegranskat)abstract
- Lower ambient temperature (Ta) requires greater energy expenditure to sustain body temperature. However, effects of Ta on human energetics may be buffered by environmental modification and behavioral compensation. We used the IAEA DLW database for adults in the USA (n = 3213) to determine the effect of Ta (−10 to +30°C) on TEE, basal (BEE) and activity energy expenditure (AEE) and physical activity level (PAL). There were no significant relationships (p > 0.05) between maximum, minimum and average Ta and TEE, BEE, AEE and PAL. After adjustment for fat-free mass, fat mass and age, statistically significant (p < 0.01) relationships between TEE, BEE and Ta emerged in females but the effect sizes were not biologically meaningful. Temperatures inside buildings are regulated at 18–25°C independent of latitude. Hence, adults in the US modify their environments to keep TEE constant across a wide range of external ambient temperatures.
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| 21. |
- Varela, AR, et al.
(författare)
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Status and Trends of Physical Activity Surveillance, Policy, and Research in 164 Countries: Findings From the Global Observatory for Physical Activity-GoPA! 2015 and 2020 Surveys
- 2023
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Ingår i: Journal of physical activity & health. - : Human Kinetics. - 1543-5474 .- 1543-3080. ; 20:2, s. 112-128
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Tidskriftsartikel (refereegranskat)abstract
- Background: Physical activity (PA) surveillance, policy, and research efforts need to be periodically appraised to gain insight into national and global capacities for PA promotion. The aim of this paper was to assess the status and trends in PA surveillance, policy, and research in 164 countries. Methods: We used data from the Global Observatory for Physical Activity (GoPA!) 2015 and 2020 surveys. Comprehensive searches were performed for each country to determine the level of development of their PA surveillance, policy, and research, and the findings were verified by the GoPA! Country Contacts. Trends were analyzed based on the data available for both survey years. Results: The global 5-year progress in all 3 indicators was modest, with most countries either improving or staying at the same level. PA surveillance, policy, and research improved or remained at a high level in 48.1%, 40.6%, and 42.1% of the countries, respectively. PA surveillance, policy, and research scores decreased or remained at a low level in 8.3%, 15.8%, and 28.6% of the countries, respectively. The highest capacity for PA promotion was found in Europe, the lowest in Africa and low- and lower-middle-income countries. Although a large percentage of the world’s population benefit from at least some PA policy, surveillance, and research efforts in their countries, 49.6 million people are without PA surveillance, 629.4 million people are without PA policy, and 108.7 million live in countries without any PA research output. A total of 6.3 billion people or 88.2% of the world’s population live in countries where PA promotion capacity should be significantly improved. Conclusion: Despite PA is essential for health, there are large inequalities between countries and world regions in their capacity to promote PA. Coordinated efforts are needed to reduce the inequalities and improve the global capacity for PA promotion.
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| 25. |
- Rohrmann, S., et al.
(författare)
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The association of education with long-term weight change in the EPIC-PANACEA cohort
- 2012
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Ingår i: European Journal of Clinical Nutrition. - : Springer Science and Business Media LLC. - 0954-3007 .- 1476-5640. ; 66:8, s. 957-963
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND/OBJECTIVES: Cross-sectionally, educational attainment is strongly associated with the prevalence of obesity, but this association is less clear for weight change during adult life. The objective of this study is to examine the association between educational attainment and weight change during adult life in the European Prospective Investigation into Cancer and Nutrition (EPIC). SUBJECTS/METHODS: EPIC is a cohort study with 361 467 participants and up to 10 years of follow-up. Educational attainment was categorized according to the highest obtained school level (primary school or less, vocational secondary training, other secondary education and university). Multivariate mixed-effects linear regression models were used to study education in relation to weight at age 20 years (self-reported), to annual change in weight between age 20 years and measured weight at recruitment, and to annual change in weight during follow-up time. RESULTS: Higher educational attainment was associated with on average a lower body mass index (BMI) at age 20 years and a lower increase in weight up to recruitment (highest vs lowest educational attainment in men: -60 g per year (95% confidence interval (CI) -80; -40), women -110 g per year (95% CI -130; -80)). Although during follow-up after recruitment an increase in body weight was observed in all educational levels, gain was lowest in men and women with a university degree (high vs low education -120 g per year (95% CI -150; -90) and -70 g per year (95% CI -90; -60), respectively). CONCLUSIONS: Existing differences in BMI between higher and lower educated individuals at early adulthood became more pronounced during lifetime, which possibly impacts on obesity-related chronic disease risk in persons with lower educational attainment.
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| 26. |
- Berg, Johanna, et al.
(författare)
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Perceived usefulness of trauma audit filters in urban India: a mixed-methods multicentre Delphi study comparing filters from the WHO and low and middle-income countries
- 2022
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Ingår i: Bmj Open. - : BMJ. - 2044-6055. ; 12:6
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Tidskriftsartikel (refereegranskat)abstract
- Objective To compare experts' perceived usefulness of audit filters from Ghana, Cameroon, WHO and those locally developed; generate context-appropriate audit filters for trauma care in selected hospitals in urban India; and explore characteristics of audit filters that correlate to perceived usefulness. Design A mixed-methods approach using a multicentre online Delphi technique. Setting Two large tertiary hospitals in urban India. Methods Filters were rated on a scale from 1 to 10 in terms of perceived usefulness, with the option to add new filters and comments. The filters were categorised into three groups depending on their origin: low and middle-income countries (LMIC), WHO and New (locally developed), and their scores compared. Significance was determined using Kruskal-Wallis test followed by Wilcoxon rank-sum test. We performed a content analysis of the comments. Results 26 predefined and 15 new filter suggestions were evaluated. The filters had high usefulness scores (mean overall score 9.01 of 10), with the LMIC filters having significantly higher scores compared with those from WHO and those newly added. Three themes were identified in the content analysis relating to medical relevance, feasibility and specificity. Conclusions Audit filters from other LMICs were deemed highly useful in the urban India context. This may indicate that the transferability of defined trauma audit filters between similar contexts is high and that these can provide a starting point when implemented as part of trauma quality improvement programmes in low-resource settings.
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| 27. |
- den Hoed, M, et al.
(författare)
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Evaluation of common genetic variants identified by GWAS for early onset and morbid obesity in population-based samples.
- 2013
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Ingår i: International Journal of Obesity. - : Springer Science and Business Media LLC. - 0307-0565 .- 1476-5497. ; 37:2
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Meta-analysis of case-control genome-wide association studies (GWAS) for early onset and morbid obesity identified four variants in/near the PRL, PTER, MAF and NPC1 genes.OBJECTIVE: We aimed to validate association of these variants with obesity-related traits in population-based samples.DESIGN: Genotypes and anthropometric traits were available in up to 31 083 adults from the Fenland, EPIC-Norfolk, Whitehall II, Ely and Hertfordshire studies and in 2042 children and adolescents from the European Youth Heart Study. In each study, we tested associations of rs4712652 (near-PRL), rs10508503 (near-PTER), rs1424233 (near-MAF) and rs1805081 (NPC1), or proxy variants (r (2)>0.8), with the odds of being overweight and obese, as well as with body mass index (BMI), percentage body fat (%BF) and waist circumference (WC). Associations were adjusted for sex, age and age(2) in adults and for sex, age, age group, country and maturity in children and adolescents. Summary statistics were combined using fixed effects meta-analysis methods.RESULTS: We had 80% power to detect odds ratios of 1.046 to 1.092 for overweight and 1.067 to 1.136 for obesity. Variants near PRL, PTER and MAF were not associated with the odds of being overweight or obese, or with BMI, %BF or WC after meta-analysis (P>0.15). The NPC1 variant rs1805081 showed some evidence of association with %BF (β=0.013 s.d./allele, P=0.040), but not with any of the remaining obesity-related traits (P>0.3).CONCLUSION: Overall, these variants, which were identified in a GWAS for early onset and morbid obesity, do not seem to influence obesity-related traits in the general population.
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| 28. |
- Ekelund, U., et al.
(författare)
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Physical activity reduces the risk of incident type 2 diabetes in general and in abdominally lean and obese men and women : the EPIC-InterAct Study
- 2012
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Ingår i: Diabetologia. - : Springer Science and Business Media LLC. - 0012-186X .- 1432-0428. ; 55:7, s. 1944-1952
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Tidskriftsartikel (refereegranskat)abstract
- We examined the independent and combined associations of physical activity and obesity with incident type 2 diabetes in men and women. The InterAct case-cohort study consists of 12,403 incident type 2 diabetes cases and a randomly selected subcohort of 16,154 individuals, drawn from a total cohort of 340,234 participants with 3.99 million person-years of follow-up. Physical activity was assessed by a four-category index. Obesity was measured by BMI and waist circumference (WC). Associations between physical activity, obesity and case-ascertained incident type 2 diabetes were analysed by Cox regression after adjusting for educational level, smoking status, alcohol consumption and energy intake. In combined analyses, individuals were stratified according to physical activity level, BMI and WC. A one-category difference in physical activity (equivalent to approximately 460 and 365 kJ/day in men and women, respectively) was independently associated with a 13% (HR 0.87, 95% CI 0.80, 0.94) and 7% (HR 0.93, 95% CI 0.89, 0.98) relative reduction in the risk of type 2 diabetes in men and women, respectively. Lower levels of physical activity were associated with an increased risk of diabetes across all strata of BMI. Comparing inactive with active individuals, the HRs were 1.44 (95% CI 1.11, 1.87) and 1.38 (95% CI 1.17, 1.62) in abdominally lean and obese inactive men, respectively, and 1.57 (95% CI 1.19, 2.07) and 1.19 (95% CI 1.01, 1.39) in abdominally lean and obese inactive women, respectively. Physical activity is associated with a reduction in the risk of developing type 2 diabetes across BMI categories in men and women, as well as in abdominally lean and obese men and women.
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| 29. |
- Langenberg, C., et al.
(författare)
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Design and cohort description of the InterAct Project : an examination of the interaction of genetic and lifestyle factors on the incidence of type 2 diabetes in the EPIC Study
- 2011
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Ingår i: Diabetologia. - : Springer. - 0012-186X .- 1432-0428. ; 54:9, s. 2272-2282
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Tidskriftsartikel (refereegranskat)abstract
- Studying gene-lifestyle interaction may help to identify lifestyle factors that modify genetic susceptibility and uncover genetic loci exerting important subgroup effects. Adequately powered studies with prospective, unbiased, standardised assessment of key behavioural factors for gene-lifestyle studies are lacking. This case-cohort study aims to investigate how genetic and potentially modifiable lifestyle and behavioural factors, particularly diet and physical activity, interact in their influence on the risk of developing type 2 diabetes. Incident cases of type 2 diabetes occurring in European Prospective Investigation into Cancer and Nutrition (EPIC) cohorts between 1991 and 2007 from eight of the ten EPIC countries were ascertained and verified. Prentice-weighted Cox regression and random-effects meta-analyses were used to investigate differences in diabetes incidence by age and sex. A total of 12,403 verified incident cases of type 2 diabetes occurred during 3.99 million person-years of follow-up of 340,234 EPIC participants eligible for InterAct. We defined a centre-stratified subcohort of 16,154 individuals for comparative analyses. Individuals with incident diabetes who were randomly selected into the subcohort (n = 778) were included as cases in the analyses. All prevalent diabetes cases were excluded from the study. InterAct cases were followed-up for an average of 6.9 years; 49.7% were men. Mean baseline age and age at diagnosis were 55.6 and 62.5 years, mean BMI and waist circumference values were 29.4 kg/m(2) and 102.7 cm in men, and 30.1 kg/m(2) and 92.8 cm in women, respectively. Risk of type 2 diabetes increased linearly with age, with an overall HR of 1.56 (95% CI 1.48-1.64) for a 10 year age difference, adjusted for sex. A male excess in the risk of incident diabetes was consistently observed across all countries, with a pooled HR of 1.51 (95% CI 1.39-1.64), adjusted for age. InterAct is a large, well-powered, prospective study that will inform our understanding of the interplay between genes and lifestyle factors on the risk of type 2 diabetes development.
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| 30. |
- Neumann, J. T., et al.
(författare)
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Application of High-Sensitivity Troponin in Suspected Myocardial Infarction
- 2019
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Ingår i: New England Journal of Medicine. - : MASSACHUSETTS MEDICAL SOC. - 0028-4793 .- 1533-4406. ; 380:26, s. 2529-2540
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundData regarding high-sensitivity troponin concentrations in patients presenting to the emergency department with symptoms suggestive of myocardial infarction may be useful in determining the probability of myocardial infarction and subsequent 30-day outcomes. MethodsIn 15 international cohorts of patients presenting to the emergency department with symptoms suggestive of myocardial infarction, we determined the concentrations of high-sensitivity troponin I or high-sensitivity troponin T at presentation and after early or late serial sampling. The diagnostic and prognostic performance of multiple high-sensitivity troponin cutoff combinations was assessed with the use of a derivation-validation design. A risk-assessment tool that was based on these data was developed to estimate the risk of index myocardial infarction and of subsequent myocardial infarction or death at 30 days. ResultsAmong 22,651 patients (9604 in the derivation data set and 13,047 in the validation data set), the prevalence of myocardial infarction was 15.3%. Lower high-sensitivity troponin concentrations at presentation and smaller absolute changes during serial sampling were associated with a lower likelihood of myocardial infarction and a lower short-term risk of cardiovascular events. For example, high-sensitivity troponin I concentrations of less than 6 ng per liter and an absolute change of less than 4 ng per liter after 45 to 120 minutes (early serial sampling) resulted in a negative predictive value of 99.5% for myocardial infarction, with an associated 30-day risk of subsequent myocardial infarction or death of 0.2%; a total of 56.5% of the patients would be classified as being at low risk. These findings were confirmed in an external validation data set. ConclusionsA risk-assessment tool, which we developed to integrate the high-sensitivity troponin I or troponin T concentration at emergency department presentation, its dynamic change during serial sampling, and the time between the obtaining of samples, was used to estimate the probability of myocardial infarction on emergency department presentation and 30-day outcomes.
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| 31. |
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| 32. |
- Scott, R. A., et al.
(författare)
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The link between family history and risk of type 2 diabetes is not explained by anthropometric, lifestyle or genetic risk factors : the EPIC-InterAct study
- 2013
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Ingår i: Diabetologia. - : Springer. - 0012-186X .- 1432-0428. ; 56:1, s. 60-69
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Tidskriftsartikel (refereegranskat)abstract
- Aims/hypothesis: Although a family history of type 2 diabetes is a strong risk factor for the disease, the factors mediating this excess risk are poorly understood. In the InterAct case-cohort study, we investigated the association between a family history of diabetes among different family members and the incidence of type 2 diabetes, as well as the extent to which genetic, anthropometric and lifestyle risk factors mediated this association.Methods: A total of 13,869 individuals (including 6,168 incident cases of type 2 diabetes) had family history data available, and 6,887 individuals had complete data on all mediators. Country-specific Prentice-weighted Cox models were fitted within country, and HRs were combined using random effects meta-analysis. Lifestyle and anthropometric measurements were performed at baseline, and a genetic risk score comprising 35 polymorphisms associated with type 2 diabetes was created.Results: A family history of type 2 diabetes was associated with a higher incidence of the condition (HR 2.72, 95% CI 2.48, 2.99). Adjustment for established risk factors including BMI and waist circumference only modestly attenuated this association (HR 2.44, 95% CI 2.03, 2.95); the genetic score alone explained only 2% of the family history-associated risk of type 2 diabetes. The greatest risk of type 2 diabetes was observed in those with a biparental history of type 2 diabetes (HR 5.14, 95% CI 3.74, 7.07) and those whose parents had been diagnosed with diabetes at a younger age (<50 years; HR 4.69, 95% CI 3.35, 6.58), an effect largely confined to a maternal family history.Conclusions/interpretation: Prominent lifestyle, anthropometric and genetic risk factors explained only a marginal proportion of the excess risk associated with family history, highlighting the fact that family history remains a strong, independent and easily assessed risk factor for type 2 diabetes. Discovering factors that will explain the association of family history with type 2 diabetes risk will provide important insight into the aetiology of type 2 diabetes.
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| 33. |
- Skogstrand, K., et al.
(författare)
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Effects of blood sample handling procedures on measurable inflammatory markers in plasma, serum and dried blood spot samples
- 2008
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Ingår i: Journal of Immunological Methods. - : Elsevier BV. - 0022-1759. ; 336:1, s. 78-84
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Tidskriftsartikel (refereegranskat)abstract
- The interests in monitoring inflammation by immunoassay determination of blood inflammatory markers call for information on the stability of these markers in relation to the handling of blood samples. The increasing use of stored biobank samples for such ventures that may have been collected and stored for other purposes, justifies the study hereof. Blood samples were stored for 0, 4, 24, and 48 h at 4 degrees C, room temperature (RT), and at 35 degrees C, respectively, before they were separated into serum or plasma and frozen. Dried blood spot samples (DBSS) were stored for 0, 1, 2, 3, 7, and 30 days at the same temperatures. 27 inflammatory markers in serum and plasma and 25 markers in DBSS were measured by a previously validated multiplex sandwich immunoassay using Luminex xMAP technology. The measurable concentrations of several cytokines in serum and plasma were significantly increased when blood samples were stored for a period of time before the centrifugation, for certain cytokines more than 1000 fold compared to serum and plasma isolated and frozen immediately after venepuncture. The concentrations in serum generally increased more than in plasma. The measurable concentrations of inflammatory markers also changed in DBSS stored under various conditions compared to controls frozen immediately after preparation, but to a much lesser degree than in plasma or serum. The study demonstrates that trustworthy measurement of several inflammatory markers relies on handling of whole blood samples at low temperatures and rapid isolation of plasma and serum. Effects of different handling procedures for all markers studied are given. DBSS proved to be a robust and convenient way to handle samples for immunoassay analysis of inflammatory markers in whole blood.
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| 34. |
- Smith, P B, et al.
(författare)
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Cultural values, sources of guidance, and their relevance to managerial behavior - A 47-nation study
- 2002
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Ingår i: Journal of Cross-Cultural Psychology. - : Sage Publications. - 0022-0221 .- 1552-5422. ; 33:2, s. 188-208
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Tidskriftsartikel (refereegranskat)abstract
- Data are presented showing how middle managers in 47 countries report handling eight specific work events. The data are used to test the ability of cultural value dimensions derived from the work of Hofstede. Trompenaars, and Schwartz to predict the specific sources of guidance on which managers rely. Focusing on sources of guidance is expected to provide a more precise basis than do generalized measures of values for understanding the behaviors that prevail within different cultures. Values are strongly predictive of reliance on those sources of guidance that are relevant to vertical relationships within organizations. Hock ever, values are less successful in predicting reliance on peers and on more tacit sources of guidance. Explaining national differences in these neglected aspects of organizational processes will require greater sensitivity to the culture-specific contexts within which they occur.
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| 35. |
- Aronsson, K. Andreas
(författare)
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Effects of wood ash on freshwater organisms and aquatic forest ecosystems
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Wood ash application (WAA) has been recommended mainly for two reasons; i) to avoid depletion of minerals in the soil due to whole tree harvest in the forestry and ii) to mitigate harmful effects of acidification of soil and surface waters. In conclusion, the effects on terrestrial ecosystems and, especially, tree growth, can be attributed to the properties of the ash, the dose applied and the specific site at which the ash is applied. The research conducted on the effects of WAA on limnological ecosystems is very limited, and the major purpose of the present thesis was to gain knowledge of the effects of wood ash to different freshwater organisms, and the more comprehensive, limnological effects of WAA in the first stream in Bispgården, Sweden. Effects of wood ash solutions on the unicellular alga Euglena gracilis Klebs, the amphipod Gammarus pulex L., and the moss Fontinalis antipyretica Hedw. were investigated under laboratory conditions. Common in all three species was the decline in performance (growth/velocity/respiration/oxygen evolution) when the concentration of wood ash exceeded 5 g/l and no adjustment of pH was done (alkaline solution). In contrast, different movement parameters (motility, upwards swimming and velocity) in E. gracilis (neutral conditions), and increased growth of F. antipyretica with increased concentrations of wood ash indicated that nutrients in the ash was bioavailable for these organisms. There was no evidence of toxic effects on the organisms from metals or other compounds as a result from exposure to wood ash solutions in the present studies. The field study was conducted in a forest area close to Bispgården, about 100 km NW from Sundsvall, Sweden. The catchment area (50 ha) of the stream Fanbergsbäcken was treated with wood ash in September of 2004 (3,000 kg/ha;selfhardened crush-ash). In general, both biological (diatoms) and chemical (pH, alkalinity, and aluminum (Al) measurements) indicators have shown no significant effect on acidification parameters from the addition of wood ash. There was, however, evidence of an increased pH during spring flood, accompanied with a decrease in the frequency of low pH values (<5.6) during spring flood. In addition to this, alkalinity was significantly higher in the period 2005-2006, compared to that of 2003. High concentrations of toxic forms of Al repeatedly occured in the stream Fanbergsbäcken, and the WAA did not affect the frequencies of high concentrations of toxic Al forms (<50 μg/l). Both the moss F. antipyretica and the leaves from Alnus incana displayed increased potassium (K) concentrations, although other nutrients did not increase from WAA. In conclusion, no evidence of WAA being effective in restoring or improving the ecological status of freshwater environments has been established, either in the literature or in the present field study. On the other hand, there were no indications of harmful effects due to WAA, either. However, we still do not know the effects of wood ash on several organisms (predominantly invertebrates) inhabiting small ponds and other, temporary or permanent, freshwater ecosystems. In the context of WAA, these environments and organisms have not attended any attention in the research published to date, and future studies are strongly encouraged.
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| 36. |
- Aronsson, K. Andreas, et al.
(författare)
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Effects on growth, photosynthesis and pigments of the freshwater moss Fontinalis antipyretica Hedw. after exposure to wood ash solution
- 2006
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 372:1, s. 236-246
-
Tidskriftsartikel (refereegranskat)abstract
- The application of wood ash from biofuel sources to the forest has been suggested as a source of nutrients for trees and for restoration of acidified soils and surface waters. Studies on the effects of wood ash on aquatic organisms and ecosystems are, however, few. This study investigated the effects of wood ash (0.1 - 10 g l-1) on the freshwater moss Fontinalis antipyretica Hedw., which has previously been shown to be a sensitive test organism for assessing environmental pollution. After nine weeks of treatment with wood ash, a significant effect of enhanced stem growth was observed at the higher concentrations (1 � 10 g l-1). The concentration of wood ash was also correlated to the growth of secondary branches. Photosynthesis (oxygen evolution after 4 h of exposure to wood ash) was significantly lower in the alkaline treatments (no pH adjustment) compared to the treatments with neutral wood ash solutions (pH adjusted to 7.5). Furthermore, photosynthesis in the alkaline wood ash treatments was significantly lower compared to the control. The ratio between the optical density value before and after acidification (OD665/665a) was higher for all wood ash concentrations compared to the control. The OD665/665a values ranged from 1.52 to 1.61 and there was a difference, however not significant, between the alkaline and the neutral treatment at 10 g l-1 wood ash. This study clearly demonstrated that wood ash may be beneficial for F. antipyretica at moderate concentrations (0.5 - 5 g l-1), particularly when sudden increase in pH is avoided.
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| 37. |
- Aronsson, K. Andreas, et al.
(författare)
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Effects on Motile Factors and Cell Growth of Euglena gracilis After Exposure to Wood Ash Solution : Assessment of Toxicity, Nutrient Availability and pH-Dependency
- 2005
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Ingår i: Water, Air and Soil Pollution. - : Springer Science and Business Media LLC. - 0049-6979 .- 1573-2932. ; 162:1-4, s. 353-368
-
Tidskriftsartikel (refereegranskat)abstract
- Wood ash application (WAA) to the forest has been suggested as a resource of nutrients for trees and for restoration of acidified soils and surface waters. However, studies of the effects of WAA on aquatic systems are few. This study investigated the effects of wood ash (1-25 g L-1) on the unicellular flagellate Euglena gracilis, which has been proved to be a sensitive test organism for assessing environmental change. Long-term (7 days) growth studies and short-term (direct, 24 and 48 h) studies of different motile factors, using the automatic biological test system Ecotox, were conducted. The results show no indication of biotoxic effects due to wood ash (adjusted to neutral) treatments. However, when no adjustments of pH in wood ash solutions were made, inhibitory effects on motile factors and cell growth were observed at higher concentrations of wood ash (10-25 g L-1) due to high pH (> 8). In tests with pH adjusted to neutral, enhanced motility was observed. These results indicate that high concentration of WAA could affect freshwater environments.
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| 38. |
- Aronsson, K. Andreas, et al.
(författare)
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Limnological effects on a first order stream after Wood Ash Application to a boreal forest catchment in Bispgården, Sweden
- 2008
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Ingår i: Forest Ecology and Management. - : Elsevier BV. - 0378-1127 .- 1872-7042. ; 255:1, s. 245-253
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Tidskriftsartikel (refereegranskat)abstract
- In Sweden, whole tree harvest is common practice, possibly leading to the depletion of mineral nutrients. Furthermore, the increased use of forestry residues for heat production has caused an increasingly growing amount of by-product consisting of wood ash. Therefore, the Swedish Forest Agency has recommended wood ash application (WAA) to replace the mineral nutrients removed by whole tree harvesting, as well as a means to mitigate the acidification of boreal forests and surface waters. In a multidisciplinary study during 2003-2006 in Bispgarden (Sweden), we have investigated the limnological effects on a first order stream after WAA (conducted in 2004; 3000 kg ha-1) to a 50-ha forested catchment. In general, no significant effects on an annual basis were found for acidification parameters, such as pH, alkalinity and toxic forms of aluminum (Al). There was, however, evidence of an increased pH during the spring flood, accompanied by a simultaneous decrease in the frequency of low pH-values (<5.6). Moreover, alkalinity increased in the years 2005 and 2006 compared to that of 2003, although the increase in 2006 was not statistically different from that in 2005 or 2003. High concentrations of Al repeatedly occurred in the stream, and the WAA did not affect the frequencies of high concentrations of toxic Al forms (>50 μg 1-1). The benthic diatom community did not change as a result of the wood ash treatment and the diatom-based index IPS (Indice de PulluoSensibilité) indicated no nutrient enrichment or organic pollution of the stream water. There were, however, indices of elevated concentrations of potassium (K) in the aquatic moss Fontinalis antipyretica and in leaves from Alder (Alnus incana). We conclude that wood ash treatment of a forested catchment with the dose and form of ash applied in this study did not modify the freshwater ecosystem of a first order stream.
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| 39. |
- Aronsson, K. Andreas, et al.
(författare)
-
Respiration measurements can assess the fitness of Gammarus pulex (L.) after exposure to different contaminants : experiments with wood ash, cadmium and aluminum
- 2005
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Ingår i: Archiv für Hydrobiologie. - : Schweizerbart. - 0003-9136. ; 164:4, s. 479-491
-
Tidskriftsartikel (refereegranskat)abstract
- Wood ash application has been suggested as a means to mitigate acidification of surface waters. However little is known about the effects of wood ash to freshwater organisms. A Clark-type oxygen electrode was used to investigate the effects of wood ash, cadmium and aluminum on the respiration of the freshwater amphipod Gammarus pulex (L.). Harmful effects following wood ash addition were primarily found to be explained by elevated pH. At high concentrations (> 1 g/l) of wood ash the respiration of G. pulex decreased when no adjustment of pH was made, a response that was negatively correlated to the elevated pH (r = -0.43). An ion-related response was also detected in the pH-adjusted (pH 7) tests, although it was not statistically significant. Cadmium proved to be sublethal in the range of 0.2-0.4mg/l in a 24-h exposure. Mortality was 100% at 0.5 and 1.0mg Cd/l. No effects were detected after exposure to Al, due to the high pH (pH 7-8) of the solutions and the subsequently low concentrations of labile monomeric Al. We demonstrate that the method described in this paper could be a useful probe for the detection of sublethal concentrations of contaminants in freshwater ecosystems.
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| 40. |
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| 41. |
- Besson, H., et al.
(författare)
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A cross-sectional analysis of physical activity and obesity indicators in European participants of the EPIC-PANACEA study
- 2009
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Ingår i: International Journal of Obesity. - : Springer Science and Business Media LLC. - 1476-5497 .- 0307-0565. ; 33:4, s. 497-506
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives: Cross-sectional data suggest a strong association between low levels of physical activity and obesity. The EPIC-PANACEA ( European Prospective Investigation into Cancer-Physical Activity, Nutrition, Alcohol, Cessation of Smoking, Eating out of home And obesity) project was designed to investigate the associations between physical activity and body mass index (BMI) and waist circumference based on individual data collected across nine European countries. Methods: In the European Prospective Investigation into Cancer and Nutrition ( EPIC), 519 931 volunteers were recruited between 1992 and 2000, of whom 405 819 had data on main variables of interest. Height, body weight and waist circumference were measured using standardized procedures. Physical activity was assessed using a validated four-category index reflecting a self-reported usual activity during work and leisure time. The associations between physical activity and BMI and waist circumference were estimated using multilevel mixed effects linear regression models, adjusted for age, total energy intake, smoking status, alcohol consumption and educational level. Results: A total of 125 629 men and 280 190 women with a mean age of 52.9 (s.d. 9.7) and 51.5 (s.d. 10.0) years, respectively were included. The mean BMI was 26.6 kg/m(2) (s.d. 3.6) in men and 25.0 kg/m(2) (s.d. 4.5) in women. Fifty percent of men and 30% of women were categorized as being active or moderately active. A one-category difference in the physical activity index was inversely associated with a difference of 0.18 kg/m(2) in the mean BMI (95% confidence interval, CI, 0.11, 0.24) and 1.04-cm (95% CI 0.82, 1.26) difference in waist circumference in men. The equivalent figures for women were 0.31 kg/m(2) (95% CI 0.23, 0.38) and 0.90 cm ( 95% CI 0.71, 1.08), respectively. Conclusions: Physical activity is inversely associated with both BMI and waist circumference across nine European countries. Although we cannot interpret the association causally, our results were observed in a large and diverse cohort independently from many potential confounders.
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| 42. |
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| 43. |
- Brink, Ebba, et al.
(författare)
-
On the road to research municipalities : Analysing transdisciplinarity in municipal ecosystem services and adaptation planning
- 2018
-
Ingår i: Sustainability Science. - : Springer. - 1862-4065 .- 1862-4057. ; 13:3, s. 765-784
-
Tidskriftsartikel (refereegranskat)abstract
- Transdisciplinary research and collaboration is widely acknowledged as a critical success factor for solution- oriented approaches that can tackle complex sustainability challenges, such as biodiversity loss, pollution, and climate-related hazards. In this context, city governments’ engagement in transdisciplinarity is generally seen as a key condition for societal transformation towards sustainability. However, empirical evidence is rare. This paper presents a self-assessment of a joint research project on ecosystem services and climate adaptation planning (ECOSIMP) undertaken by four universities and seven Swedish municipalities. We apply a set of design principles and guiding questions for transdisciplinary sustainability projects and, on this basis, identify key aspects for supporting university–municipality collaboration. We show that: (1) selecting the number and type of project stakeholders requires more explicit consideration of the purpose of societal actors’ participation; (2) concrete, interim benefits for participating practitioners and organisations need to be continuously discussed; (3) promoting the ‘inter’, i.e., interdisciplinary and inter-city learning, can support transdisciplinarity and, ultimately, urban sustainability and long-term change. In this context, we found that design principles for transdisciplinarity have the potential to (4) mitigate project shortcomings, even when transdisciplinarity is not an explicit aim, and (5) address differences and allow new voices to be heard. We propose additional guiding questions to address shortcomings and inspire reflexivity in transdisciplinary projects.
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| 44. |
- Brito, Ema C, 1961-, et al.
(författare)
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PPARGC1A sequence variation and cardiovascular risk-factor levels : a study of the main genetic effects and gene x environment interactions in children from the European youth heart study
- 2009
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Ingår i: Diabetologia. - : Springer Science and Business Media LLC. - 0012-186X .- 1432-0428. ; 52:4, s. 609-613
-
Tidskriftsartikel (refereegranskat)abstract
- AIMS/HYPOTHESIS: The PPARGC1A gene coactivates multiple nuclear transcription factors involved in cellular energy metabolism and vascular stasis. In the present study, we genotyped 35 tagging polymorphisms to capture all common PPARGC1A nucleotide sequence variations and tested for association with metabolic and cardiovascular traits in 2,101 Danish and Estonian boys and girls from the European Youth Heart Study, a multicentre school-based cross-sectional cohort study. METHODS: Fasting plasma glucose concentrations, anthropometric variables and blood pressure were measured. Habitual physical activity and aerobic fitness were objectively assessed using uniaxial accelerometry and a maximal aerobic exercise stress test on a bicycle ergometer, respectively. RESULTS: In adjusted models, nominally significant associations were observed for BMI (rs10018239, p = 0.039), waist circumference (rs7656250, p = 0.012; rs8192678 [Gly482Ser], p = 0.015; rs3755863, p = 0.02; rs10018239, beta = -0.01 cm per minor allele copy, p = 0.043), systolic blood pressure (rs2970869, p = 0.018) and fasting glucose concentrations (rs11724368, p = 0.045). Stronger associations were observed for aerobic fitness (rs7656250, p = 0.005; rs13117172, p = 0.008) and fasting glucose concentrations (rs7657071, p = 0.002). None remained significant after correcting for the number of statistical comparisons. We proceeded by testing for gene x physical activity interactions for the polymorphisms that showed nominal evidence of association in the main effect models. None of these tests was statistically significant. CONCLUSIONS/INTERPRETATION: Variants at PPARGC1A may influence several metabolic traits in this European paediatric cohort. However, variation at PPARGC1A is unlikely to have a major impact on cardiovascular or metabolic health in these children.
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| 45. |
- Cooray, S., et al.
(författare)
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Anti-tumour necrosis factor treatment for the prevention of ischaemic events in patients with deficiency of adenosine deaminase 2 (DADA2)
- 2021
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Ingår i: Rheumatology. - : Oxford University Press (OUP). - 1462-0324 .- 1462-0332. ; 60:9, s. 4373-4378
-
Tidskriftsartikel (refereegranskat)abstract
- Objective To evaluate the impact of anti-Tumour Necrosis Factor-alpha (anti-TNF) treatment on the occurrence of vasculitic ischaemic events in patients with deficiency of adenosine deaminase 2 (DADA2). Methods A retrospective analysis of DADA2 patients referred from six centres to Great Ormond Street Hospital for Children was conducted. Ischaemic events, vasculitic disease activity, biochemical, immunological, and radiological features were compared, before and after anti-TNF treatment. Results A total of 31 patients with genetically confirmed DADA2 were included in the study. The median duration of active disease activity prior to anti-TNF treatment was 73months (inter-quartile range [IQR] 27.5-133.5months). Twenty seven/31 patients received anti-TNF treatment for a median of 32months (IQR 12.0-71.5months). The median event rate of central nervous system (CNS) and non-CNS ischemic events before anti-TNF treatment was 2.37 per 100 patient-months (IQR 1.25-3.63); compared with 0.00 per 100 patient-months (IQR 0.0-0.0) post-treatment (p< 0.0001). Paediatric vasculitis activity score (PVAS) was also significantly reduced: median score of 20/63 (IQR 13.0-25.8/63) pre-treatment vs. 2/63 (IQR 0.0-3.8/63) following anti-TNF treatment (p< 0.0001), with mild livedoid rash being the main persisting feature. Anti-TNF treatment was not effective for severe immunodeficiency or bone marrow failure, which required haematopoietic stem cell transplantation (HSCT). Conclusion Anti-TNF treatment significantly reduced the incidence of ischaemic events and other vasculitic manifestations of DADA2, but was not effective for immunodeficiency or bone marrow failure.
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| 46. |
- den Hoed, Marcel, 1980-, et al.
(författare)
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Genetic susceptibility to obesity and related traits in childhood and adolescence influence of loci identified by genome-wide association studies
- 2010
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Ingår i: Diabetes. - Alexandria, USA : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 59:11, s. 2980-2988
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: Large-scale genome-wide association (GWA) studies have thus far identified 16 loci incontrovertibly associated with obesity-related traits in adults. We examined associations of variants in these loci with anthropometric traits in children and adolescents.Research design and methods: Seventeen variants representing 16 obesity susceptibility loci were genotyped in 1,252 children (mean +/- SD age 9.7 +/- 0.4 years) and 790 adolescents (15.5 +/- 0.5 years) from the European Youth Heart Study (EYHS). We tested for association of individual variants and a genetic predisposition score (GPS-17), calculated by summing the number of effect alleles, with anthropometric traits. For 13 variants, summary statistics for associations with BMI were meta-analyzed with previously reported data (N-total = 13,071 children and adolescents). Results: In EYHS, 15 variants showed associations or trends with anthropometric traits that were directionally consistent with earlier reports in adults. The meta-analysis showed directionally consistent associations with BMI for all 13 variants, of which 9 were significant (0.033-0.098 SD/allele; P < 0.05). The near-TMEM18 variant had the strongest effect (0.098 SD/allele P = 8.5 x 10(-11)). Effect sizes for BMI tended to be more pronounced in children and adolescents than reported earlier in adults for variants in or near SEC16B, TMEM18, and KCTD15, (0.028-0.035 SD/allele higher) and less pronounced for rs925946 in BDNF (0.028 SD/allele lower). Each additional effect allele in the GPS-17 was associated with an increase of 0.034 SD in BMI (P = 3.6 x 10(-5)), 0.039 SD, in sum of skinfolds (P = 1.7 x 10(-7)), and 0.022 SD in waist circumference (P = 1.7 X 10(-4)), which is comparable with reported results in adults (0.039 SD/allele for BMI and 0.033 SD/allele for waist circumference).Conclusions: Most obesity susceptibility loci identified by GWA studies in adults are already associated with anthropometric traits in children/adolescents. Whereas the association of some variants may differ with age, the cumulative effect size is similar. Diabetes 59:2980-2988, 2010
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| 47. |
- Ekelund, A, et al.
(författare)
-
Effects of iso- and hypervolemic hemodilution on regional cerebral blood flow and oxygen delivery for patients with vasospasm after aneurysmal subarachnoid hemorrhage.
- 2002
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Ingår i: Acta Neurochirurgica. - : Springer Science and Business Media LLC. - 0001-6268. ; 144:7, s. 703-713
-
Tidskriftsartikel (refereegranskat)abstract
- SUMMARY:BACKGROUND: Arterial vasospasm after subarachnoid hemorrhage may cause cerebral ischemia. Treatment with hemodilution, reducing blood viscosity, and hypervolemia, increasing cardiac performance and distending the vasospastic artery, are clinically established methods to improve blood flow through the vasospastic arterial bed.METHOD: Eight patients with transcranial Doppler verified vasospasm after subarachnoid hemorrhage were investigated with global (two-dimensional (133)Xenon) and regional (three-dimensional (99 m)Tc-HMPAO) cerebral blood flow (CBF) measurements, before and after 1/iso- and 2/hypervolemic hemodilution. Hematocrit was reduced to 0.28 from 0.36. Hypervolemia was achieved by increasing blood volume by 1100 ml.FINDINGS: Isovolemic hemodilution increased global cerebral blood flow from 52.25+/-10.12 to 58.56+/-11.73 ml * 100 g(-1) * min(-1) (p<0.05), but after hypervolemic hemodilution CBF returned to 51.38+/-11.34 ml * 100 g(-1) * min(-1). Global cerebral delivery rate of oxygen (CDRO(2)) decreased from 7.94+/-1.92 to 6.98+/-1.66 ml * 100 g(-1) * min(-1) (p<0.001) during isovolemic hemodilution and remained reduced, 6.77+/-1.60 ml * 100 g(-1) * min(-1) (p<0.001), after the hypervolemic hemodilution. As a test of the hemodilution effect on regional CDRO(2) an ischemic threshold was defined as the maximal amount of oxygen transported by a CBF of 10 ml * 100 g(-1) * min(-1) at a Hb 140 g/l which corresponds to a CDRO(2) of 1.83 ml * 100 g(-1) * min(-1). The brain volume with a CDRO(2) exceeding the ichemic threshold was 1300+/-236 ml before intervention. After isovolemic hemodilution the non-ischemic brain volume was reduced to 1206+/-341 (p<0,003). After hypervolemic hemodilution the non-ischemic brain volume remained reduced at 1228+/-347 ml (p<0.05).INTERPRETATION: The present study of controlled isovolemic hemodilution demonstrated increased global CBF, but there was a pronounced reduction in oxygen delivery capacity. Both CBF and CDRO(2) remained decreased during further hypervolemic hemodilution. We conclude that hemodilution to hematocrit 0.28 is not beneficial for patients with cerebral vasospasm after SAH.
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| 48. |
- Ekelund, A, et al.
(författare)
-
Transcranial cerebral oximetry related to transcranial Doppler after aneurysmal subarachnoid haemorrhage
- 1998
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Ingår i: Acta Neurochirurgica. - : Springer Science and Business Media LLC. - 0001-6268 .- 0942-0940. ; 140:10, s. 1029-1036
-
Tidskriftsartikel (refereegranskat)abstract
- Noninvasive methods for detecting cerebral artery vasospasm, still a serious complication following aneurysmal subarachnoid haemorrhage, are of vital interest. Up-to-date transcranial Doppler ultrasound (TCD) has proved to be sensitive in detecting vasospasm in the middle cerebral artery, but has less accuracy for other cerebral arteries. Transcranial cerebral oximetry (TCCO) is a new non-invasive technique which may increase the reliability for detecting cerebral ischaemia. The purpose of the present study was to evaluate a putative correlation between TCCO and TCD. We examined the two hemispheres in 14 patients with the aim of evaluating a proposed correlation between TCD and TCCO. Analysis of all absolute values (maximum TCD mFV and minimum TCCO saturation, respectively) in all series indicate a correlation between TCCO and TCD, p < 0.01, r = -0.62. All patients with TCD mean flow velocity > 120 cm/s also presented TCCO saturation < 60%. Conversely, all patients with normal TCCO saturation (> or = 63%) presented normal or moderately increased TCD velocities. In clinical neurosurgical practice it is of great interest if a true correlation between TCD and TCCO exists. The present results support the assumption that TCCO may enhance the reliability for detecting cerebral ischaemia after aneurysmal subarachnoid haemorrhage.
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| 49. |
- Ekelund, K., et al.
(författare)
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AFM study of lipid monolayers. 1. Pressure-induced phase behavior of single and mixed fatty acids
- 1999
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Ingår i: Langmuir. - : American Chemical Society (ACS). - 0743-7463 .- 1520-5827. ; 15:20, s. 6946-6949
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Tidskriftsartikel (refereegranskat)abstract
- Monolayers of palmitic (C16:0) and lignoceric acid (C24:0) and their equimolar mixture were transferred to a hydrophilic mica substrate at various surface pressures and investigated by means of atomic force microscopy (AFM) in contact and lateral force modes. The first-order transition of lignoceric acid gives a plateau region, representing a liquid expanded to liquid condensed phase transition in the pressure-area isotherm. This was visualized by AFM as stripes of a condensed phase within the expanded phase, exhibiting a small height difference but a significant difference in friction. The corresponding phase transition of the palmitic acid was continuous, and no changes of the Langmuir-Blodgett films with respect to pressure were observed with AFM. Both the surface pressure-area isotherms and the direct observations of domains of irregular size and shape using the AFM showed that lignoceric and palmitic acid were immiscible. The height difference between the domains was 1.1 nm corresponding to the difference in hydrocarbon chain length of the two fatty acids.
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| 50. |
- Ekelund, K., et al.
(författare)
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Rectangular solid domains in ceramide-cholesterol monolayers - 2D crystals
- 2000
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Ingår i: Biochimica et Biophysica Acta - Biomembranes. - 0005-2736. ; 1464:1
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Tidskriftsartikel (refereegranskat)abstract
- Very small rectangular domains were observed by atomic force microscopy in binary monolayers of synthetic ceramides and cholesterol. When the cholesterol content is increased the domains are bigger although the rectangular shape is retained. The almost perfect shape of the domains indicates two-dimensional single ceramide crystals. Lipid domains in monolayers of this particular shape and size have to our knowledge not been reported in the literature previously.
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