| 2341. |
- Logares, Ramiro, et al.
(författare)
-
Contrasting prevalence of selection and drift in the community structuring of bacteria and microbial eukaryotes
- 2018
-
Ingår i: Environmental Microbiology. - : Wiley. - 1462-2912 .- 1462-2920. ; 20:6, s. 2231-2240
-
Tidskriftsartikel (refereegranskat)abstract
- Whether or not communities of microbial eukaryotes are structured in the same way as bacteria is a general and poorly explored question in ecology. Here, we investigated this question in a set of planktonic lake microbiotas in Eastern Antarctica that represent a natural community ecology experiment. Most of the analysed lakes emerged from the sea during the last 6000 years, giving rise to waterbodies that originally contained marine microbiotas and that subsequently evolved into habitats ranging from freshwater to hypersaline. We show that habitat diversification has promoted selection driven by the salinity gradient in bacterial communities (explaining approximate to 72% of taxa turnover), while microeukaryotic counterparts were predominantly structured by ecological drift (approximate to 72% of the turnover). Nevertheless, we also detected a number of microeukaryotes with specific responses to salinity, indicating that albeit minor, selection has had a role in the structuring of specific members of their communities. In sum, we conclude that microeukaryotes and bacteria inhabiting the same communities can be structured predominantly by different processes. This should be considered in future studies aiming to understand the mechanisms that shape microbial assemblages.
|
|
| 2342. |
- Lorenz, M. W., et al.
(författare)
-
Predictive value for cardiovascular events of common carotid intima media thickness and its rate of change in individuals at high cardiovascular risk - Results from the PROG-IMT collaboration
- 2018
-
Ingår i: Plos One. - : Public Library of Science (PLoS). - 1932-6203. ; 13:4
-
Tidskriftsartikel (refereegranskat)abstract
- Aims Carotid intima media thickness (CIMT) predicts cardiovascular (CVD) events, but the predictive value of CIMT change is debated. We assessed the relation between CIMT change and events in individuals at high cardiovascular risk. From 31 cohorts with two CIMT scans (total n = 89070) on average 3.6 years apart and clinical follow-up, subcohorts were drawn: (A) individuals with at least 3 cardiovascular risk factors without previous CVD events, (B) individuals with carotid plaques without previous CVD events, and (C) individuals with previous CVD events. Cox regression models were fit to estimate the hazard ratio (HR) of the combined endpoint (myocardial infarction, stroke or vascular death) per standard deviation (SD) of CIMT change, adjusted for CVD risk factors. These HRs were pooled across studies. In groups A, B and C we observed 3483, 2845 and 1165 endpoint events, respectively. Average common CIMT was 0.79mm (SD 0.16mm), and annual common CIMT change was 0.01mm (SD 0.07mm), both in group A. The pooled HR per SD of annual common CIMT change (0.02 to 0.43mm) was 0.99 (95% confidence interval: 0.95-1.02) in group A, 0.98 (0.93-1.04) in group B, and 0.95 (0.89-1.04) in group C. The HR per SD of common CIMT (average of the first and the second CIMT scan, 0.09 to 0.75mm) was 1.15 (1.07-1.23) in group A, 1.13 (1.05-1.22) in group B, and 1.12 (1.05-1.20) in group C. We confirm that common CIMT is associated with future CVD events in individuals at high risk. CIMT change does not relate to future event risk in high-risk individuals.
|
|
| 2343. |
- Lowe, Robert, et al.
(författare)
-
Affective-associative two-process theory: a neurocomputational account of partial reinforcement extinction effects
- 2017
-
Ingår i: Biological Cybernetics. - : Springer Science and Business Media LLC. - 0340-1200 .- 1432-0770. ; 111:5-6, s. 365-388
-
Tidskriftsartikel (refereegranskat)abstract
- The partial reinforcement extinction effect (PREE) is an experimentally established phenomenon: behavioural response to a given stimulus is more persistent when previously inconsistently rewarded than when consistently rewarded. This phenomenon is, however, controversial in animal/human learning theory. Contradictory findings exist regarding when the PREE occurs. One body of research has found a within-subjects PREE, while another has found a within-subjects reversed PREE (RPREE). These opposing findings constitute what is considered the most important problem of PREE for theoreticians to explain. Here, we provide a neurocomputational account of the PREE, which helps to reconcile these seemingly contradictory findings of within-subjects experimental conditions. The performance of our model demonstrates how omission expectancy, learned according to low probability reward, comes to control response choice following discontinuation of reward presentation (extinction). We find that a PREE will occur when multiple responses become controlled by omission expectation in extinction, but not when only one omission-mediated response is available. Our model exploits the affective states of reward acquisition and reward omission expectancy in order to differentially classify stimuli and differentially mediate response choice. We demonstrate that stimulus-response (retrospective) and stimulus-expectation-response (prospective) routes are required to provide a necessary and sufficient explanation of the PREE versus RPREE data and that Omission representation is key for explaining the nonlinear nature of extinction data.
|
|
| 2344. |
- Lu, Zhengyao, et al.
(författare)
-
Natural decadal variability of global vegetation growth in relation to major decadal climate modes
- 2023
-
Ingår i: Environmental Research Letters. - : IOP Publishing. - 1748-9326 .- 1748-9318. ; 18:1
-
Tidskriftsartikel (refereegranskat)abstract
- The ongoing climate change can modulate the behavior of global vegetation and influence the terrestrial biosphere carbon sink. Past observation-based studies have mainly focused on the linear trend or interannual variability of the vegetation greenness, but could not explicitly deal with the effect of natural decadal variability due to the short length of observations. Here we put the variabilities revealed by remote sensing-based global leaf area index (LAI) from 1982 to 2015 into a long-term perspective with the help of ensemble Earth system model simulations of the historical period 1850-2014, with a focus on the low-frequency variability in the global LAI during the growing season. Robust decadal variability in the observed and modelled LAI was revealed across global terrestrial ecosystems, and it became stronger toward higher latitudes, accounting for over 50% of the total variability north of 40 degrees N. The linkage of LAI decadal variability to major natural decadal climate modes, such as the El Nino-Southern Oscillation decadal variability (ENSO-d), the Pacific decadal oscillation (PDO), and the Atlantic multidecadal oscillation (AMO), was analyzed. ENSO-d affects LAI by altering precipitation over large parts of tropical land. The PDO exerts opposite impacts on LAI in the tropics and extra-tropics due to the compensation between the effects of temperature and growing season length. The AMO effects are mainly associated with anomalous precipitation in North America and Europe but are mixed with long-term climate change impacts due to the coincident phase shift of the AMO which also induces North Atlantic basin warming. Our results suggest that the natural decadal variability of LAI can be largely explained by these decadal climate modes (on average 20% of the variance, comparable to linear changes, and over 40% in some ecosystems) which also can be potentially important in inducing the greening of the Earth of the past decades.
|
|
| 2345. |
- Ludwigs, Karin, et al.
(författare)
-
Poor inter-observer agreement in anatomical classifications of infrapopliteal arterial disease due to mandatory selection of only one target artery
- 2023
-
Ingår i: Acta Radiologica. - : SAGE Publications. - 0284-1851 .- 1600-0455. ; 64:3, s. 1298-1306
-
Tidskriftsartikel (refereegranskat)abstract
- Background Established anatomical classifications of infrapopliteal arterial lesion severity are based on assessment of only one target artery, not including all infrapopliteal arteries although multivessel revascularization is common. Purpose To investigate the reproducibility of one of these classifications and a new aggregated score. Material and Methods A total of 68 patients undergoing endovascular infrapopliteal revascularization at Sahlgrenska University Hospital during 2008-2016 were included. Preoperative magnetic resonance angiographies (MRA) and digital subtraction angiographies (DSA) were evaluated by three blinded observers in random order, using the infrapopliteal TransAtlantic Inter-Society Consensus (TASC) II classification. An aggregated score, the Infrapopliteal Total Atherosclerotic Burden (I-TAB) score, including all infrapopliteal arteries, was constructed and used for comparison. Results Inter-observer agreement on lesion severity for each evaluated artery was good; Krippendorff's alpha for MRA 0.64-0.79 and DSA 0.66-0.84. Inter-observer agreement on TASC II grade, based on the selected target artery as stipulated, was poor; Krippendorff's alpha 0.14 (95% confidence interval [CI]=-0.05 to 0.30) for MRA and 0.48 (95% CI=0.33-0.61) for DSA. Inter-observer agreement for the new I-TAB score was good; Krippendorff's alpha 0.76 (95% CI=0.70-0.81) for MRA and 0.79 (95% CI=0.74-0.84) for DSA. Conclusion Reproducible assessment of infrapopliteal lesion severity can be achieved for separate arteries with both MRA and DSA using the TASC II definitions. However, poor inter-observer agreement in selecting the target artery results in low reproducibility of the overall infrapopliteal TASC II grade. An aggregated score, such as I-TAB, results in less variability and may provide a more robust evaluation tool of atherosclerotic disease severity.
|
|
| 2346. |
- Lund, Anna My, et al.
(författare)
-
Unpasteurised maternal breast milk is positively associated with growth outcomes in extremely preterm infants
- 2020
-
Ingår i: Acta Paediatrica. - Oxford, UK : Wiley. - 0803-5253 .- 1651-2227. ; 109:6
-
Tidskriftsartikel (refereegranskat)abstract
- Aim Extrauterine growth restriction is common among extremely preterm infants. We explored whether intake of unpasteurised maternal milk (MM) and pasteurised donor milk (DM) was associated with longitudinal growth outcomes and neonatal morbidities in extremely preterm infants. Methods Observational study of 90 preterm infants born between 2013 and 2015 in Gothenburg, Sweden. Data were prospectively collected on nutritional and breast milk intakes during the first 28 days. Results Ninety infants (39 girls and 51 boys) with a median gestational age of 25.3 (22.7-27.9) weeks were evaluated. MM intake (mL/kg/d) correlated positively with almost all z-scores for weight, length and head circumference at 28 postnatal days and at postmenstrual age (PMA) 32 and 36 weeks. After multivariable adjustment, MM intake and weight z-score at 28 postnatal days and at PMA 32 and 36 weeks remained significantly associated. Infants consuming >= 80% MM had more favourable weight z-scores at PMA 32 and 36 weeks. Intake of DM did not correlate with any growth outcomes. Infants without retinopathy of prematurity had a significantly higher intake of MM (mL/kg/d). Conclusion Unpasteurised MM was positively associated with longitudinal growth outcomes. Motivating mothers to provide their infants with their own milk after preterm birth should be emphasised.
|
|
| 2347. |
- Lundgren, Christine, et al.
(författare)
-
PAM50 subtyping and ROR score add long-term prognostic information in premenopausal breast cancer patients
- 2022
-
Ingår i: Npj Breast Cancer. - : Springer Science and Business Media LLC. - 2374-4677. ; 8:1
-
Tidskriftsartikel (refereegranskat)abstract
- PAM50 intrinsic subtyping and risk of recurrence (ROR) score are approved for risk profiling in postmenopausal women. We aimed to examine their long-term prognostic value in terms of breast cancer-free interval (BCFi) and overall survival (OS) (n = 437) in premenopausal women randomised to 2 years of tamoxifen versus no systemic treatment irrespective of hormone-receptor status. Intrinsic subtyping added independent prognostic information in patients with oestrogen receptor-positive/human epidermal growth factor 2-negative tumours for BCFi and OS after maximum follow-up (overall P-value 0.02 and 0.006, respectively) and those with high versus low ROR had worse prognosis (maximum follow-up: hazard ratio (HR)(BCFi): 1.70, P 0.04). The prognostic information by ROR was similar regarding OS and in multivariable analysis. These results support that PAM50 subtyping and ROR score provide long-term prognostic information in premenopausal women. Moreover, tamoxifen reduced the incidence of breast cancer events only in patients with Luminal A(PAM50) tumours (0-10 years: HRBCFi(Luminal A): 0.41, HRBCFi(Luminal B): 1.19, P-interaction = 0.02).
|
|
| 2348. |
- Lundgren Elfström, Magnus, 1971, et al.
(författare)
-
Relations between coping strategies and health-related quality of life in patients with spinal cord lesion.
- 2005
-
Ingår i: Journal of rehabilitation medicine : official journal of the UEMS European Board of Physical and Rehabilitation Medicine. - : Medical Journals Sweden AB. - 1650-1977 .- 1651-2081. ; 37:1, s. 9-16
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Although the use of appropriate coping strategies has been suggested to be a key factor in determining successful adjustment to severe physical illness/disability, little systematic support for this link has been found. We investigated relationships between spinal cord lesion-related coping strategies and health-related quality of life when studying for sociodemographic, disability-related and social support variables. DESIGN AND SUBJECTS: We studied 256 persons with traumatically acquired spinal cord lesion (=1 year) from a typical rural/urban Swedish area in a cross-sectional design. METHODS: Coping measure was the Spinal Cord Lesion-related Coping Strategies Questionnaire. Outcome measures were the Spinal Cord Injury Quality of Life Questionnaire, the Short-Form 36 Health Survey version 2.0, and a standardized global question of overall quality of life. Multiple regressions were performed. RESULTS: Coping strategies were clear correlates of health-related quality of life when sociodemographic, disability-related and social support variables were studied. The relationship between coping strategies and quality of life was: the more revaluation of life values (Acceptance) and the fewer tendencies towards dependent behaviour (Social reliance) the better the health-related quality of life. CONCLUSION: Our results suggest that greater focus needs to be directed to coping strategies and to ways of facilitating adaptive outcomes in rehabilitation.
|
|
| 2349. |
- Lundgren Elfström, Magnus, 1971, et al.
(författare)
-
Relationships between locus of control, coping strategies and emotional well-being in persons with spinal cord lesion
- 2006
-
Ingår i: J Clin Psychol Med Settings. - : Springer Science and Business Media LLC. - 1068-9583 .- 1573-3572. ; 13:1, s. 93-104
-
Tidskriftsartikel (refereegranskat)abstract
- Relations between locus of control, coping strategies and emotional well-being in persons with traumatically acquired spinal cord lesion were examined. The sample included 132 community-residing adults. Structural equation modelling, including confirmatory factor analysis, was used. A model was hypothesized based on the transactional theory of stress and coping where coping strategies mediated the relation between locus of control and emotional well-being. The model showed acceptable fit to the data and was compared with five alternative models. The alternative models fitted the data less well or were difficult to interpret. In the preferred model, persons indicating internal control reported more coping strategies (Acceptance, Fighting spirit) related to increased well-being, whereas persons indicating external control reported a coping strategy (Social reliance) related to poorer well-being. The findings support the stress and coping framework in medical rehabilitation and illustrate why some persons need coping effectiveness training to enhance emotional adjustment.
|
|
| 2350. |
- Lundin, Andreas, et al.
(författare)
-
Veno-arterial CO2 difference and lactate for prediction of early mortality after cardiac arrest
- 2023
-
Ingår i: Acta Anaesthesiologica Scandinavica. - : Wiley. - 0001-5172 .- 1399-6576. ; 67:5, s. 655-662
-
Tidskriftsartikel (refereegranskat)abstract
- Patients admitted to intensive care after cardiac arrest are at risk of circulatory shock and early mortality due to cardiovascular failure. The aim of this study was to evaluate the ability of the veno-arterial pCO(2) difference ( increment pCO(2); central venous CO2 - arterial CO2) and lactate to predict early mortality in postcardiac arrest patients. This was a pre-planned prospective observational sub-study of the target temperature management 2 trial. The sub-study patients were included at five Swedish sites. Repeated measurements of increment pCO(2) and lactate were conducted at 4, 8, 12, 16, 24, 48, and 72 h after randomization. We assessed the association between each marker and 96-h mortality and their prognostic value for 96-h mortality. One hundred sixty-three patients were included in the analysis. Mortality at 96 h was 17%. During the initial 24 h, there was no difference in increment pCO(2) levels between 96-h survivors and non-survivors. increment pCO(2) measured at 4 h was associated with an increased risk of death within 96 h (adjusted odds ratio: 1.15; 95% confidence interval [CI]: 1.02-1.29; p = .018). Lactate levels were associated with poor outcome over multiple measurements. The area under the receiving operating curve to predict death within 96 h was 0.59 (95% CI: 0.48-0.74) and 0.82 (95% CI: 0.72-0.92) for increment pCO(2) and lactate, respectively. Our results do not support the use of increment pCO(2) to identify patients with early mortality in the postresuscitation phase. In contrast, non-survivors demonstrated higher lactate levels in the initial phase and lactate identified patients with early mortality with moderate accuracy.
|
|
