| 1. |
- Bergkvist, Bo, et al.
(författare)
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Pools and fluxes of carbon in three Norway spruce ecosystems along a climatic gradient in Sweden
- 2008
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Ingår i: Biogeochemistry. - : Springer Science and Business Media LLC. - 0168-2563 .- 1573-515X. ; 89:1, s. 7-25
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents an integrated analysis of organic carbon (C) pools in soils and vegetation, within-ecosystem fluxes and net ecosystem exchange (NEE) in three 40-year old Norway spruce stands along a north-south climatic gradient in Sweden, measured 2001-2004. A process-orientated ecosystem model (CoupModel), previously parameterised on a regional dataset, was used for the analysis. Pools of soil organic carbon (SOC) and tree growth rates were highest at the southernmost site (1.6 and 2.0-fold, respectively). Tree litter production (litterfall and root litter) was also highest in the south, with about half coming from fine roots (< 1 mm) at all sites. However, when the litter input from the forest floor vegetation was included, the difference in total litter input rate between the sites almost disappeared (190-233 g C m(-2) year(-1)). We propose that a higher N deposition and N availability in the south result in a slower turnover of soil organic matter than in the north. This effect seems to overshadow the effect of temperature. At the southern site, 19% of the total litter input to the O horizon was leached to the mineral soil as dissolved organic carbon, while at the two northern sites the corresponding figure was approx. 9%. The CoupModel accurately described general C cycling behaviour in these ecosystems, reproducing the differences between north and south. The simulated changes in SOC pools during the measurement period were small, ranging from -8 g C m(-2) year(-1) in the north to +9 g C m(-2) year(-1) in the south. In contrast, NEE and tree growth measurements at the northernmost site suggest that the soil lost about 90 g C m(-2) year(-1).
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| 2. |
- Björnström, Karin, 1971-, et al.
(författare)
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Characterisation of the signal transduction cascade caused by propofol in rat neurons : From the GABAA receptor to the cytoskeleton
- 2008
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Ingår i: Journal of Physiology and Pharmacology. - 0867-5910 .- 1899-1505. ; 59:3, s. 617-632
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Tidskriftsartikel (refereegranskat)abstract
- The anaesthetic propofol interacts with the GABAA receptor, but its cellular signalling pathways are not fully understood. Propofol causes reorganisation of the actin cytoskeleton into ring structures in neurons. Is this reorganisation a specific effect of propofol as apposed to GABA, and which cellular pathways are involved? We used fluorescence-marked actin in cultured rat neurons to evaluate the percentage of actin rings caused by propofol or GABA in combination with rho, rho kinase (ROK), PI3-kinase or tyrosine kinase inhibitors, with or without the presence of extracellular calcium. Confocal microscopy was performed on propofol-stimulated cells and changes in actin between cellular compartments were studied with Western blot. Propofol (3 μg·ml-1), but not GABA (5 μM), caused transcellular actin ring formation, that was dependent on influx of extracellular calcium and blocked by rho, ROK, PI3-kinase or tyrosine kinase inhibitors. Propofol uses rho/ROK to translocate actin from the cytoskeleton to the membrane and its actin ring formation is dependent on an interaction site close to the GABA site on the GABAA receptor. GABA does not cause actin rings, implying that this is a specific effect of propofol.
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| 3. |
- Björnström, Karin, et al.
(författare)
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Rho and Rho Kinase are involved in the signal transduction cascade caused by propofol
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Background: Propofol is known to interact with the γ-aminobutyric acidA (GABAA) receptor, however, activating the receptor alone is not sufficient for producing anaesthesia. Propofol tyresine phosphorylates the GABAA receptor and reorganises the actin cytoskeleton, eausing ring structures and rnembrane ruffles. Propofol, but not GABA, the endogenous tigand for the GABAA receptor, tyresine phosphorylates actin, both in the membrane and cytoskeletal fractions of the neuron.Aim: How does propofol cause the actin reorganisation and is this a specific effect of propofol? Is the small membrane associated G-protein rho involved in the signal cascade towards the actin reorganisation?Methods: Westem blotting (WB) was used to visualize tyresine phosphorylated immunoprecipitated proteins and changes in actin between the different cellularcompartments after inhibition with rho (C3 exotoxin) and rho kinase (ROK) (HA-1077) inhibitors. Fluoreseenee mireoscopy after rhodamine-phalloidin labelling of actin was used to calculate the number of actin ring structures caused by propofol or GABA, in same experiments combined with pre-incubation with C3 exotoxin, HA- 1077 or the tyrosine kinase inhibitor Herbimycin A. Propofol-stimulated cells were studied with confocal microscopy.Results: Propofol eaused an increased tyresine phosphorylation, that was reduced by C3 exotoxin, of a 160 kDa protein after two minutes stimulation. The 160 kDa protein is still unidentified. The actin ring structures caused by propofol was shown with confocal microscopy to go almost through the entire cell. The amount of rings were reduced by C3 exatoxin as well as HA-1077. Furthermore, w hen a tyrosine kinase bioeker was used no ring structures were formed. However, GABA did not produce any ring structures. When the actin content of the cellular campartments were analysed, C3 exatoxin treated cells showed an increased amount of actin in the cytoskeletal fraction, simultaneausly with a decrease in both the membrane and the cytosol fractions. The ROK bioeker on ly eaused a reduction of actin in the cytosol/membrane fractions, but no increase was observed in the cytoskeleton.Conclusion: Propofol, but not GABA, eauses actin ring structures in neurons. Propofol uses the rho and rho kinase pathway to reorganize the actin cytoskeleton into ring structures, which is also dependent on a tyresine klnase. Propofol also eauses an unidentified rho dependent 160 kDa protein to be tyresine phosphorylated. The activation eaused by propofol of rho and rho kinase causes actin to be moved from the cytoskeleton to the cell membrane and cytosol. This reorganisation of actin might influence the GABAA receptor by keeping it open, thus allowing the cell to be hyperpolarized for longer time, and consequently maintain anaesthesia.
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| 4. |
- Hadad, Ronza, 1984-, et al.
(författare)
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First National Genomic Epidemiological Study of Neisseria gonorrhoeae Strains Spreading Across Sweden in 2016
- 2022
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Ingår i: Frontiers in Microbiology. - : Frontiers Media S.A.. - 1664-302X. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- The increasing transmission and antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a global health concern with worrying trends of decreasing susceptibility to also the last-line extended-spectrum cephalosporin (ESC) ceftriaxone. A dramatic increase of reported gonorrhea cases has been observed in Sweden from 2016 and onward. The aim of the present study was to comprehensively investigate the genomic epidemiology of all cultured N. gonorrhoeae isolates in Sweden during 2016, in conjunction with phenotypic AMR and clinical and epidemiological data of patients. In total, 1279 isolates were examined. Etest and whole-genome sequencing (WGS) were performed, and epidemiological data obtained from the Public Health Agency of Sweden. Overall, 51.1%, 1.7%, and 1.3% resistance to ciprofloxacin, cefixime, and azithromycin, respectively, was found. No isolates were resistant to ceftriaxone, however, 9.3% of isolates showed a decreased susceptibility to ceftriaxone and 10.5% to cefixime. In total, 44 penA alleles were found of which six were mosaic (n = 92). Using the typing schemes of MLST, NG-MAST, and NG-STAR; 133, 422, and 280 sequence types, respectively, and 93 NG-STAR clonal complexes were found. The phylogenomic analysis revealed two main lineages (A and B) with lineage A divided into two main sublineages (A1 and A2). Resistance and decreased susceptibility to ESCs and azithromycin and associated AMR determinants, such as mosaic penA and mosaic mtrD, were predominantly found in sublineage A2. Resistance to cefixime and azithromycin was more prevalent among heterosexuals and MSM, respectively, and both were predominantly spread through domestic transmission. Continuous surveillance of the spread and evolution of N. gonorrhoeae, including phenotypic AMR testing and WGS, is essential for enhanced knowledge regarding the dynamic evolution of N. gonorrhoeae and gonorrhea epidemiology.
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| 5. |
- Hadad, Ronza, 1984-, et al.
(författare)
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GENOMIC EPIDEMIOLOGY OF NEISSERIA GONORRHOEAE ISOLATES IN SWEDEN-2016 NATIONAL STUDY
- 2021
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Ingår i: Sexually Transmitted Infections. - : BMJ Publishing Group Ltd. - 1368-4973 .- 1472-3263. ; 97:Suppl. 1, s. A135-A135
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Background: The number of reported cases of gonorrhoea in Sweden continuously increased from an incidence of 7.8 per 100 000 inhabitants in 2009 to 31.4 in 2019. The largest increase in incidence was observed during 2016–2017. No national molecular epidemiological study investigating the population of N. gonorrhoeae circulating in Sweden has been performed in the last two decades. Our aim was to examine the antimicrobial resistance (AMR) and genome-based epidemiology, in conjunction to patient epidemiological data, of all gonococcal isolates (n=1279; one isolate per case) from gonorrhoea cases in Sweden during 2016.Methods: AMR testing was performed using Etest, and MICs were interpreted using current clinical resistance breakpoints from EUCAST. All isolates were whole genome sequenced using Illumina HiSeq X platform. Patient epidemiological data was obtained from the Public Health Agency of Sweden.Results: The gonorrhoea patients consisted of 252 (19.7%) women and 1027 men (80.3%). The medium age of the women was 27.4 years and of the men 32.1 years. Regarding sexual orientation, 619 (48.4%) reported homosexual, 605 (47.3%) heterosexual, 31 (2.4%) bisexual, and 24 (1.9%) did not report. Most prevalent countries of infection were Sweden (n=875, 68.4%), followed by Thailand (n=70, 5.5%) and Germany (n=32, 2.5%).Overall, the phenotypic AMR was as follows: ceftriaxone and spectinomycin (0%), cefixime (1.7%), azithromycin (1.3%) and ciprofloxacin (51.1%). A high concordance between phenotypic AMR and molecular AMR determinants was found. Results from the genome-based epidemiology are currently in final analysis.Conclusions: AMR in N. gonorrhoeae in Sweden remains low, in particular to ceftriaxone and azithromycin that is recommended internationally for dual therapy. The incidence increases in Sweden appear to be driven by increased spread among men-who-have-sex-with-men but also younger heterosexuals of both genders. This is the first national genome-based epidemiological study for N. gonorrhoeae in Sweden and final genomic results are pending.
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| 6. |
- Hellström-Westas, Lena, et al.
(författare)
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Low risk of seizure recurrence after early withdrawal of antiepileptic treatment in the neonatal period
- 1995
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Ingår i: Archives of disease in childhood. Fetal and neonatal edition. - 1359-2998. ; 72:2, s. 97-101
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Tidskriftsartikel (refereegranskat)abstract
- The risk of seizure recurrence within the first year of life was evaluated in infants with neonatal seizures diagnosed with a combination of clinical signs, amplitude-integrated electroencephalogram (EEG) monitoring, and standard EEG. Fifty eight of 283 (4.5%) neonates in tertiary level neonatal intensive care had seizures. The mortality in the infants with neonatal seizures was 36.2%. In 31 surviving infants antiepileptic treatment was discontinued after one to 65 days (median 4.5 days). Three infants received no antiepileptic treatment, two continued with prophylactic antiepileptic treatment. Seizure recurrence was present in only three cases (8.3%)--one infant receiving prophylaxis, one treated for 65 days, and in one infant treated for six days. Owing to the small number of infants with seizure recurrence, no clinical features could be specifically related to an increased risk of subsequent seizures. When administering antiepileptic treatment, one aim was to abolish both clinical and electrographical seizures. Another goal was to minimise the duration of treatment and to keep the treatment as short as possible. It is suggested that treating neonatal seizures in this way may not only reduce the risk of subsequent seizure recurrence, but may also minimise unnecessary non-specific prophylactic treatment for epilepsy.
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| 7. |
- Huang, Qinghai, et al.
(författare)
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Women’s Career Patterns : A Study of Swedish Women Born in the 1950s
- 2007
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Ingår i: Journal of Occupational and Organizational Psychology. - 0963-1798 .- 2044-8325. ; 80:3, s. 387-412
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Tidskriftsartikel (refereegranskat)abstract
- Patterns of career development have been found to be an important factor for longterm career rewards and well-being. However, existing career models excessively focus on men or elite women and upon paid work, typically without considering other roles. Based on a life course perspective, this study aimed to identify women's career development patterns by examining the dynamic interactions between individuals' involvement in working life and other career-related domains of life. Career biographies, from the ages of 16 to 43, were recorded through retrospective reports from a representative sample of Swedish women (N = 549) participating in a longitudinal programme on individual development. Seven career-related activities were coded and combined into career sequences covering the entire period. Data were analysed using optimal matching, and nine distinct career patterns -- disparate in terms of the timing, ordering and duration of activities -- were identified. There were significant differences between the career patterns in early educational aspirations and early sexual experiences, as well as in life-role values and socio-economic status in middle age. With respect to the consequences of career patterns for well-being, there were significant differences in self-rated health but not in job satisfaction or life satisfaction. The diversity of patterns is discussed from a perspective that takes account of both life course theory and the choices made by individual women in a society that provides childcare facilities, parental leave and other types of support to working parents.
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| 8. |
- Isaksson, Kerstin, et al.
(författare)
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Women's career patterns in Sweden: A life-event approach.
- 2006
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Ingår i: Community, Work and Family. - : Informa UK Limited. - 1366-8803 .- 1469-3615. ; 9:4, s. 479-500
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Tidskriftsartikel (refereegranskat)abstract
- Although research on and models of career patterns often are implicitly assumed to be of general validity, they are usually coloured by their cultural, ethnical, and historical background and - until recently - by a lack of gender perpective. A review of research on women and career development (Philips & Imhoff, 1997) concluded that research in the recent decade took important steps but that critical gaps still remain. One such gap concerns changes and transitions in women's careers. The general aim of this paper is to describe career patterns over the life course of women born in the 1950s - in terms of shape, level, and stability. Data were taken from work histories in the interviews of a sample of Swedish women aged 43 (n=109) as part of a longitudinal study. Career patterns were plotted based on life events related to education, family, and work. Results revealed relative stability of labour force participation, but not of work hours over the life course. Career progress in terms of moving to higher career levels was a common feature of the cohort. However, continuous full-time work (from 16 until 43) was highly unusual and almost entirely limited to women with no children.
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| 9. |
- Kasurinen, Ville, et al.
(författare)
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Latent heat exchange in the boreal and arctic biomes
- 2014
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 20:11, s. 3439-3456
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Forskningsöversikt (refereegranskat)abstract
- In this study latent heat flux (E) measurements made at 65 boreal and arctic eddy-covariance (EC) sites were analyses by using the Penman-Monteith equation. Sites were stratified into nine different ecosystem types: harvested and burnt forest areas, pine forests, spruce or fir forests, Douglas-fir forests, broadleaf deciduous forests, larch forests, wetlands, tundra and natural grasslands. The Penman-Monteith equation was calibrated with variable surface resistances against half-hourly eddy-covariance data and clear differences between ecosystem types were observed. Based on the modeled behavior of surface and aerodynamic resistances, surface resistance tightly control E in most mature forests, while it had less importance in ecosystems having shorter vegetation like young or recently harvested forests, grasslands, wetlands and tundra. The parameters of the Penman-Monteith equation were clearly different for winter and summer conditions, indicating that phenological effects on surface resistance are important. We also compared the simulated E of different ecosystem types under meteorological conditions at one site. Values of E varied between 15% and 38% of the net radiation in the simulations with mean ecosystem parameters. In general, the simulations suggest that E is higher from forested ecosystems than from grasslands, wetlands or tundra-type ecosystems. Forests showed usually a tighter stomatal control of E as indicated by a pronounced sensitivity of surface resistance to atmospheric vapor pressure deficit. Nevertheless, the surface resistance of forests was lower than for open vegetation types including wetlands. Tundra and wetlands had higher surface resistances, which were less sensitive to vapor pressure deficits. The results indicate that the variation in surface resistance within and between different vegetation types might play a significant role in energy exchange between terrestrial ecosystems and atmosphere. These results suggest the need to take into account vegetation type and phenology in energy exchange modeling.
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| 10. |
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