| 1. |
- Berg, Hans E., et al.
(författare)
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Threshold-automated CT measurements of muscle size and radiological attenuation in multiple lower-extremity muscles of older individuals
- 2020
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Ingår i: Clinical Physiology and Functional Imaging. - : WILEY. - 1475-0961 .- 1475-097X. ; 40:3, s. 165-172
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Tidskriftsartikel (refereegranskat)abstract
- Muscle atrophy and fat infiltration, two indicators of deconditioning and weakness in elderly frail patients, are typically assessed by means of manual image analysis from computed tomography (CT) scans. As this time-consuming image analysis limits its wider use in clinical studies, the use of tissue thresholds to semi-automatically assess muscle composition has been suggested. Here, we aimed to investigate the relationship between manual and semi-automated analysis of both cross-sectional area (CSA) and radiological attenuation (RA), in multiple muscles of the lower extremities in aged (77 +/- 6 years) sedentary individuals (n = 40). The participants underwent CT scans of their lower limbs, including hip, thigh and calf muscles. The subsequent analysis of CSA and RA was conducted using both manual segmentation and semi-automatic thresholds (-30 to +150 Hounsfield units). Automated measurements were generally strongly correlated with manually encircled CSA in all muscle groups (R = 0.79-0.99, p < .05) and shortened the analysis time by 70% (p < .05). In m. iliopsoas, however, the CSA became overestimated (15%, p < .05) with thresholded measurements, while the assessment of both CSA and RA was underestimated in muscles with high-fat content (i.e., the gluteal muscles) and in individuals with high-fat infiltration. In conclusion, using the semi-automated technique with conventional thresholds is a time-saving method that delivers accurate gross size of the muscle groups, particularly in the thigh. However, caution should be exercised when using semi-automated techniques for assessing CSA and fat infiltration in muscles with high-fat content.
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| 2. |
- Hedenstedt, Anna, et al.
(författare)
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B cell polygenic risk scores associate with anti-dsDNA antibodies and nephritis in systemic lupus erythematosus.
- 2023
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Ingår i: Lupus science & medicine. - : BMJ Publishing Group Ltd. - 2053-8790. ; 10:2
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Tidskriftsartikel (refereegranskat)abstract
- B cell function and autoantibodies are important in SLE pathogenesis. In this work, we aimed to investigate the impact of cumulative SLE B cell genetics on SLE subphenotype and autoantibody profile.Female patients with SLE (n=1248) and healthy controls (n=400) were genotyped using Illumina's Global Screening Array. Two polygenic risk scores (PRSs), one representing B cell genes and the other B cell activation genes, were calculated for each individual using risk loci for SLE in genes assigned to B cell-related pathways according to the Kyoto Encyclopedia of Genes and Genomes, Gene Ontology and Reactome Databases.Double-stranded DNA (dsDNA) antibodies were more prevalent among patients with a high compared with a low SLE B cell PRS (OR 1.47 (1.07 to 2.01), p=0.018), and effect sizes were augmented in patients with human leucocyte antigen (HLA) risk haplotypes HLA-DRB1*03:01 and HLA-DRB1*15:01 (DRB1*03/15 -/- (OR 0.99 (0.56 to 1.77), p=0.98; DRB1*03/15 +/- or -/+ (OR 1.64 (1.06 to 2.54), p=0.028; and DRB1*03/15 +/+ (OR 4.47 (1.21 to 16.47), p=0.024). Further, a high compared with a low B cell PRS was associated with low complement levels in DRB1*03/15 +/+ patients (OR 3.92 (1.22 to 12.64), p=0.022). The prevalence of lupus nephritis (LN) was higher in patients with a B cell activation PRS above the third quartile compared with patients below (OR 1.32 (1.00 to 1.74), p=0.048).High genetic burden related to B cell function is associated with dsDNA antibody development and LN. Assessing B cell PRSs may be important in order to determine immunological pathways influencing SLE and to predict clinical phenotype.
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| 3. |
- Jardim, Fabiana, et al.
(författare)
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Virus as a figure of geontopower or how to practice Foucault now? : A conversation with Elizabeth A. Povinelli
- 2023
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Ingår i: Foucault Studies. - : Copenhagen Business School Press. - 1832-5203. ; :35, s. 211-231
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Elizabeth A. Povinelli, Franz Boas Professor at Columbia University, is a philosopher and anthropologist who has critically engaged with Michel Foucault’s ideas as well as scholarship inspired by his works. Povinelli has been dedicated to research on colonialism within liberalism and is also a filmmaker and founding member of The Karrabing Film Collective. The film collective is part of a larger organization of Aboriginal peoples and artists living in the Australian Northern Territory that refuses ‘fantasies of sovereignty and property’.[1]As Povinelli shares with us during the interview, her trajectory was constituted in the middle of the 1980s following her life-changing encounter with the elders in Belyuen in the Australian Northern Territory. In the wake of that encounter, and with urgent issues raised about indigeneity due to changes in Australian law, Povinelli has been working even closer with her Karrabing family. The changes in law both acknowledged Aboriginal peoples' rights to their territory and imposed certain ideas of identity, family and culture, producing an entanglement between rights and government. These efforts to manage differences – cultural, race, gender – are problematized and deciphered in Povinelli’s ethnographic work with a focus on how late settler liberalism has been reconfigured with novel expressions of colonialism and imperialism.
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| 4. |
- Listou, Tore, et al.
(författare)
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Performance Based Logistics : A Norwegian-Swedish Perspective
- 2020
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Ingår i: Necesse. - 2464-353X .- 2535-2903. ; 5:3, s. 118-135
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Tidskriftsartikel (refereegranskat)abstract
- Performance Based Logistics (PBL) as a support strategy for defence systems has been coined as a paradigmatic change within defence acquisition and maintenance. Originating from the defence industry, the concept has been adopted in many defence organisations. Although studies of its applicability has identified both enablers and barriers for implementation, these studies predominantly are performed in a few large nations. How the concept corresponds with a small state perspective needs to be addressed. Further on, perceived outputs of PBL practices would differ between the acquisition organisation, the supplier of PBL services, and the users of the services. Understanding these differences in perceptions would give valuable knowledge about how to design PBL contracts. Thirdly; assuming that PBL contracts indeed result in improved effectiveness, adapting the involved organisations to a new way of managing logistics should be accompanied by related organisational change processes. The purpose with this study is to contextualise the concept and define barriers and enablers for PBL in a small state perspective (represented by Norway and Sweden), identify different stakeholders’ expectations for output, and explore whether implementing such a concept is perceived as a significantly new way of organising defence supply chains with an accompanying organisational change strategy.
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| 5. |
- Skoglund, Elisabeth, et al.
(författare)
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Functional improvements to 6 months of physical activity are not related to changes in size or density of multiple lower-extremity muscles in mobility-limited older individuals
- 2022
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Ingår i: Experimental Gerontology. - : Elsevier BV. - 0531-5565 .- 1873-6815. ; 157
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Tidskriftsartikel (refereegranskat)abstract
- Older adults are encouraged to engage in multicomponent physical activity, which includes aerobic and muscle-strengthening activities. The current work is an extension of the Vitality, Independence, and Vigor in the Elderly 2 (VIVE2) study - a 6-month multicenter, randomized, placebo-controlled trial of physical activity and nutritional supplementation in community dwelling 70-year-old seniors. Here, we examined whether the magnitude of changes in muscle size and quality differed between major lower-extremity muscle groups and related these changes to functional outcomes. We also examined whether daily vitamin-D-enriched protein supplementation could augment the response to structured physical activity. Forty-nine men and women (77 ± 5 yrs) performed brisk walking, muscle-strengthening exercises for the lower limbs, and balance training 3 times weekly for 6 months. Participants were randomized to daily intake of a nutritional supplement (20 g whey protein + 800 IU vitamin D), or a placebo. Muscle cross-sectional area (CSA) and radiological attenuation (RA) were assessed in 8 different muscle groups using single-slice CT scans of the hip, thigh, and calf at baseline and after the intervention. Walking speed and performance in the Short Physical Performance Battery (SPPB) were also measured. For both CSA and RA, there were muscle group × time interactions (P < 0.01). Significant increases in CSA were observed in 2 of the 8 muscles studied, namely the knee extensors (1.9%) and the hip adductors (2.8%). For RA, increases were observed in 4 of 8 muscle groups, namely the hip flexors (1.1 HU), hip adductors (0.9 HU), knee extensors (1.2 HU), and ankle dorsiflexors (0.8 HU). No additive effect of nutritional supplementation was observed. While walking speed (13%) and SPPB performance (38%) improved markedly, multivariate analysis showed that these changes were not associated with the changes in muscle CSA and RA after the intervention. We conclude that this type of multicomponent physical activity program results in significant improvements in physical function despite relatively small changes in muscle size and quality of some, but not all, of the measured lower extremity muscles involved in locomotion.
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| 6. |
- Skoglund, Elisabeth, et al.
(författare)
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Longitudinal Muscle and Myocellular Changes in Community-Dwelling Men Over Two Decades of Successful Aging : The ULSAM Cohort Revisited
- 2020
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Ingår i: The journals of gerontology. Series A, Biological sciences and medical sciences. - : Oxford University Press (OUP). - 1079-5006 .- 1758-535X. ; 75:4, s. 654-663
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Tidskriftsartikel (refereegranskat)abstract
- Participants of the population-based Uppsala longitudinal study of adult men (ULSAM) cohort reaching more than 88 years of age (survivors, S) were investigated at age 70, 82, and 88-90 and compared at 70 years with non-survivors (NS) not reaching 82 years. Body composition, muscle mass and muscle histology were remarkably stable over 18 years of advanced aging in S. Analysis of genes involved in muscle remodeling showed that S had higher mRNA levels of myogenic differentiation factors (Myogenin, MyoD), embryonic myosin (eMyHC), enzymes involved in regulated breakdown of myofibrillar proteins (Smad2, Trim32, MuRF1,) and NCAM compared with healthy adult men (n = 8). S also had higher mRNA levels of eMyHC, Smad 2, MuRF1 compared with NS. At 88 years, S expressed decreased levels of Myogenin, MyoD, eMyHC, NCAM and Smad2 towards those seen in NS at 70 years. The gene expression pattern of S at 70 years was likely beneficial since they maintained muscle fiber histology and appendicular lean body mass until advanced age. The expression pattern at 88 years may indicate a diminished muscle remodeling coherent with a decline of reinnervation capacity and/or plasticity at advanced age.
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| 7. |
- Skoglund, Elisabeth
(författare)
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Muscular aging and its relation to physical activity and function : longitudinal and cross-sectional analyses
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- With age, muscle mass decreases and muscle function and strength decline, which is associated with loss of independence, hospitalization, morbidity and mortality. The aim of this thesis was to investigate the mechanisms involved in the age-related loss of muscle mass, physical function and strength by 1) studying gene expression and muscle morphology in muscle biopsies of vastus lateralis longitudinally (Study I) and muscle morphology cross-sectionally (Study II) in a cohort of older men, i.e. the Uppsala Longitudinal Study of Adult Men (ULSAM, Study I and II), and in men with a lifelong history of endurance training (Study II), 2) evaluation of a semi-automated and manual method to analyze the cross-sectional area and radiological attenuation (RA) of eight lower extremity muscle groups in mobility-limited individuals aged over 70 years (Study III), 3) evaluation of the effect of a 6-month physical activity intervention on muscle size and density of the same locomotor muscles, with or without an oral nutritional supplement containing protein and vitamin D (study IV). In study I, muscle morphology including fiber types, fiber area, and satellite cells (SC) and 14 genes involved in muscle remodeling were analyzed at ages 70 and 88-90 years. Study II examined muscle morphology in seven elite endurance athletes aged 82-92 and 19 ULSAM men aged 87-91 years, who were divided into high and low function groups based on tests for physical function and strength. In Study III and IV, measurements were done in a cohort of mobility limited individuals over 70 years (the Vitality, Independence, and Vigor in the Elderly 2 Study, VIVE2). Eight different locomotor muscles were measured using both the semi-automated and manual method and two independent observers performed the manual measurements (Study III) and manual measurement only (Study IV). In Study I, type II fibers decreased with age, whereas fibers co-expressing myosin heavy chain type I+IIA increased. Expression of genes involved in muscle remodeling were higher at age 70 compared to healthy adult men. Some of these genes were also expressed at higher levels at age 70 than at age 88-90 and in those who survived beyond age 82 compared to those who died before that age. The higher expression of genes involved in remodeling at age 70 in survivors were considered beneficial since muscle mass was relatively stable between 82 and 88 years. Lifelong endurance training was associated with a better oxidative profile, with more type I fibers, more capillaries and fewer COX negative fibers even after 80 years of age (Study II). Manual and semi-automated measurements of area and RA correlated well between methods, especially in normal-density muscles, as shown in study III. A 6-month physical activity intervention increased area and RA in some but not all muscle groups and these changes were not related to the more pronounced changes observed in physical function (study IV). In conclusion, muscle plasticity decreases in very old men, as evidenced by altered gene expression profile. Morphological characteristics are to some extent unrelated to physical function, while lifelong endurance training is associated with some beneficial morphological features even at very advanced ages. There is also a reduced muscular adaptive response to physical activity in old men and women and these changes are at least partially unrelated to physical function.
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| 8. |
- Skoglund, Elisabeth, et al.
(författare)
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Skeletal muscle morphology, satellite cells, and oxidative profile in relation to physical function and lifelong endurance training in very old men
- 2023
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Ingår i: Journal of applied physiology. - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 134:2, s. 264-275
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Tidskriftsartikel (refereegranskat)abstract
- In the current study, we compared muscle morphology in three advanced aging cohorts that differed in physical function, includ-ing a unique cohort of lifelong endurance athletes. Biopsies from the vastus lateralis muscle of seven lifelong endurance athletes (EAs) aged 82-92 yr, and 19 subjects from the Uppsala Longitudinal Study of Adult Men (ULSAM) aged 87-91 yr were analyzed. ULSAM subjects were divided into high-(n = 9, HF) and low-(n = 10, LF) function groups based on strength and physical function tests. The analysis included general morphology, fiber type and cross-sectional area, capillarization, deficient cytochrome c oxi-dase (COX) activity, number of myonuclei and satellite cells, and markers of regeneration and denervation. Fibers with central nuclei and/or nuclear clumps were observed in all groups. EA differed from LF and HF by having a higher proportion of type I fibers, 52% more capillaries in relation to fiber area, fewer COX-negative fibers, and less variation in fiber sizes (all P < 0.05). There were no differences between the groups in the number of myonuclei and satellite cells per fiber, and no significant differ-ences between LF and HF (P > 0.05). In conclusion, signs of aging were evident in the muscle morphology of all groups, but neither endurance training status nor physical function influenced signs of regeneration and denervation processes. Lifelong en-durance training, but not higher physical function, was associated with higher muscle oxidative capacity, even beyond the age of 80.NEW & NOTEWORTHY Here we show that lifelong endurance training, but not physical function, is associated with higher mus-cle oxidative capacity, even beyond the age of 80 yr. Neither endurance training status nor physical function was significantly associated with satellite cells or markers of regeneration and denervation in muscle biopsies from these very old men.
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| 9. |
- von Berens, Åsa, et al.
(författare)
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Sarcopenic obesity and associations with mortality in older women and men – a prospective observational study
- 2020
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Ingår i: BMC Geriatrics. - : Springer Science and Business Media LLC. - 1471-2318 .- 1471-2318. ; 20:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: The combined effect of sarcopenia and obesity, i.e., sarcopenic obesity, has been associated with disability and worse outcomes in older adults, but results are conflicting. The objectives of this study were to describe the prevalence of sarcopenic obesity (SO) in older adults, and to examine how the risk of mortality is associated with SO and its various components. Methods: Data were obtained from two Swedish population studies, the Gothenburg H70 Birth Cohort Studies of 521 women and men at the age of 75, and the Uppsala Longitudinal Study of Adult Men (ULSAM), which included 288 men aged 87 years. Sarcopenia was defined using the recently updated EWGSOP2 definition. Obesity was defined by any of three established definitions: body mass index ≥30 kg/m2 , fat mass > 30%/ > 42% or waist circumference ≥ 88 cm/≥102 cm for women and men, respectively. The Kaplan-Meier survival curve and the Cox proportional hazard model were used for 10-year and 4-year survival analyses in the H70 and ULSAM cohorts, respectively. Results: SO was observed in 4% of the women and 11% of the men in the H70 cohort, and in 10% of the ULSAM male cohort. The 75-year-old women with SO had a higher risk (HR 3.25, 95% confidence interval (1.2–8.9)) of dying within 10 years compared to those with a “normal” phenotype. A potential similar association with mortality among the 75-year-old men was not statistically significant. In the older men aged 87 years, obesity was associated with increased survival. Conclusions: SO was observed in 4–11% of community-dwelling older adults. In 75-year-old women SO appeared to associate with an increased risk of dying within 10 years. In 87-year-old men, the results indicated that obesity without sarcopenia was related to a survival benefit over a four-year period.
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