| 1. |
- Gamborg, Michael, et al.
(författare)
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Birth weight and systolic blood pressure in adolescence and adulthood : meta-regression analysis of sex- and age-specific results from 20 Nordic studies
- 2007
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Ingår i: American Journal of Epidemiology. - : Oxford University Press (OUP). - 0002-9262 .- 1476-6256. ; 166:6, s. 634-645
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Tidskriftsartikel (refereegranskat)abstract
- The authors investigated the shape, sex- and age-dependency, and possible confounding of the association between birth weight and systolic blood pressure (SBP) in 197,954 adults from 20 Nordic cohorts (birth years 1910-1987), one of which included 166,249 Swedish male conscripts. Random-effects meta-regression analyses were performed on estimates obtained from age- and sex-stratified analyses within each of the cohorts. There was an inverse association between birth weight and SBP, irrespective of adjustment for concurrent body mass index. The association was linear for males, but for females with a birth weight greater than 4 kg, SBP increased with birth weight (p < 0.01). The association was stronger in the older age groups (p < 0.05), although this could have been a birth cohort effect. The association was stronger among females than among males (p = 0.005) when birth weight was less than or equal to 4 kg. The estimated effect of birth weight on SBP at age 50 years was -1.52 mmHg/kg (95% confidence interval: -2.27, -0.77) in men and -2.80 mmHg/kg (95% confidence interval: -3.85, -1.76) in women. Exclusion of the Swedish conscripts produced nearly identical results. This meta-analysis supports the evidence of an inverse birth weight-SBP association, regardless of adjustment for concurrent body size. It also reveals important heterogeneity in the shape and strength of the association by sex and age.
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| 2. |
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| 3. |
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- 2019
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Tidskriftsartikel (refereegranskat)
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| 4. |
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| 5. |
- Bengtsson, Calle, 1934, et al.
(författare)
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Body configuration as a predictor of mortality: comparison of five anthropometric measures in a 12 year follow-up of the Norwegian HUNT 2 study
- 2011
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:10, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- Background Distribution of body fat is more important than the amount of fat as a prognostic factor for life expectancy. Despite that, body mass index (BMI) still holds its status as the most used indicator of obesity in clinical work. Methods We assessed the association of five different anthropometric measures with mortality in general and cardiovascular disease (CVD) mortality in particular using Cox proportional hazards models. Predictive properties were compared by computing integrated discrimination improvement and net reclassification improvement for two different prediction models. The measures studied were BMI, waist circumference, hip circumference, waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR). The study population was a prospective cohort of 62,223 Norwegians, age 20–79, followed up for mortality from 1995–1997 to the end of 2008 (mean follow-up 12.0 years) in the Nord-Trøndelag Health Study (HUNT 2). Results After adjusting for age, smoking and physical activity WHR and WHtR were found to be the strongest predictors of death. Hazard ratios (HRs) for CVD mortality per increase in WHR of one standard deviation were 1.23 for men and 1.27 for women. For WHtR, these HRs were 1.24 for men and 1.23 for women. WHR offered the greatest integrated discrimination improvement to the prediction models studied, followed by WHtR and waist circumference. Hip circumference was in strong inverse association with mortality when adjusting for waist circumference. In all analyses, BMI had weaker association with mortality than three of the other four measures studied. Conclusions Our study adds further knowledge to the evidence that BMI is not the most appropriate measure of obesity in everyday clinical practice. WHR can reliably be measured and is as easy to calculate as BMI and is currently better documented than WHtR. It appears reasonable to recommend WHR as the primary measure of body composition and obesity.
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| 6. |
- Bengtsson, Calle, 1934, et al.
(författare)
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Is the use of cholesterol in mortality risk algorithms in clinical guidelines valid? Ten years prospective data from the Norwegian HUNT 2 study
- 2012
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Ingår i: Journal of Evaluation in Clinical Practice. - : Wiley. - 1356-1294. ; 18:1, s. 159-168
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Tidskriftsartikel (refereegranskat)abstract
- Rationale, aims and objectives Many clinical guidelines for cardiovascular disease (CVD) prevention contain risk estimation charts/calculators. These have shown a tendency to overestimate risk, which indicates that there might be theoretical flaws in the algorithms. Total cholesterol is a frequently used variable in the risk estimates. Some studies indicate that the predictive properties of cholesterol might not be as straightforward as widely assumed. Our aim was to document the strength and validity of total cholesterol as a risk factor for mortality in a well-defined, general Norwegian population without known CVD at baseline. Methods We assessed the association of total serum cholesterol with total mortality, as well as mortality from CVD and ischaemic heart disease (IHD), using Cox proportional hazard models. The study population comprises 52 087 Norwegians, aged 20–74, who participated in the Nord-Trøndelag Health Study (HUNT 2, 1995–1997) and were followed-up on cause-specific mortality for 10 years (510 297 person-years in total). Results Among women, cholesterol had an inverse association with all-cause mortality [hazard ratio (HR): 0.94; 95% confidence interval (CI): 0.89–0.99 per 1.0 mmol L−1 increase] as well as CVD mortality (HR: 0.97; 95% CI: 0.88–1.07). The association with IHD mortality (HR: 1.07; 95% CI: 0.92–1.24) was not linear but seemed to follow a ‘U-shaped’ curve, with the highest mortality <5.0 and ≥7.0 mmol L−1. Among men, the association of cholesterol with mortality from CVD (HR: 1.06; 95% CI: 0.98–1.15) and in total (HR: 0.98; 95% CI: 0.93–1.03) followed a ‘U-shaped’ pattern. Conclusion Our study provides an updated epidemiological indication of possible errors in the CVD risk algorithms of many clinical guidelines. If our findings are generalizable, clinical and public health recommendations regarding the ‘dangers’ of cholesterol should be revised. This is especially true for women, for whom moderately elevated cholesterol (by current standards) may prove to be not only harmless but even beneficial.
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| 7. |
- Ebbesson, Lars O. E., et al.
(författare)
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Exposure to continuous light disrupts retinal innervation of the preoptic nucleus during parr-smolt transformation in Atlantic salmon
- 2007
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Ingår i: Aquaculture. - : Elsevier BV. - 0044-8486 .- 1873-5622. ; 273:2-3, s. 345-349
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Konferensbidrag (refereegranskat)abstract
- High quality salmon smolts are essential for aquaculture, enhancement programs and wild populations. However, intensification of aquaculture smolt production and changes in natural habitats can cause sub-optimal environmental conditions, which may result in poor smolt quality. The salmon brain, as the integrator of environmental information, plays a focal role in relaying this information through the light-brain-pituitary axis, which includes retinal and pineal innervation of the hypothalamus. Here we investigated the effect of rearing juvenile Atlantic salmon, Salmo salar, under constant light (LL) on optic nerve fiber growth into the hypothalamus. This was compared with the normal increased fiber growth in fish reared under a simulated-natural photoperiod (LDN). Parr were sampled from the LDN group in February and from the LDN and LL groups in May (peak smolt status for the LDN group). Retinohypothalamic projections to the preoptic area were traced using 1, 1'-dioctadecyl-3,3, 3,3-tetramethylindocarbocyanine perchlorate (DiI) and confocal laser scanning microscopy. Data showed that parr exposed to LL did not develop the same extensive retinal innervation to the preoptic nucleus (NPO) observed in control salmon smolts raised under LDN. Since the cells in NPO are central pituitary regulatory neurones, the increased retinohypothalamic innervation during normal smoltification may be responsible for the increased endocrine response to photoperiod information. The deprivation of photoperiod information, during continuous light exposure, may inhibit the natural developmental program to proceed during the parr-smolt transformation. (C) 2007 Elsevier B.V. All rights reserved.
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| 8. |
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| 9. |
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| 10. |
- Hansson, Lars-Olof, et al.
(författare)
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Comparison between Chicken and Rabbit Antibody Based Particle Enhanced Cystatin C Reagents for Immunoturbidimetry
- 2008
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Ingår i: Journal of immunoassay & immunochemistry. - : Informa UK Limited. - 1532-1819 .- 1532-4230. ; 29:1, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- We have compared three commercial particle enhanced cystatin C reagents. One of the reagents utilizes chicken antibodies and the other two reagents are rabbit antibody based. We show that the chicken antibody based reagent yields a higher delta absorbance when reacting with the antigen. IgY coupled to latex particles show a strong scatter response even at high antigen concentrations in contrast to the steep decline in scatter previously reported for IgY antibodies in solution. The reagent also showed a low CV for duplicate samples. Laying hens thus seems as an interesting source of antibodies for particle-enhanced immunoassays.
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| 11. |
- Holmesland, Anne-Lise, et al.
(författare)
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Open Dialogues in social networks : professional identity and transdisciplinary collaboration
- 2010
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Ingår i: International Journal of Integrated Care. - 1568-4156 .- 1568-4156. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Aim: The aim of this article is to explore the challenges connected to the transformation and emergence of professional identity in transdisciplinary multi-agency network meetings and the use of Open Dialogue. Introduction: The empirical findings have been taken from a clinical project in southern Norway concerning multi-agency network meetings with persons between 14 and 25 years of age. The project explores how these meetings are perceived by professionals working in various sectors. Methodology: Data was collected through three interviews conducted with two focus groups, the first comprising health care professionals and the second professionals from the social and educational sectors. Content analysis was used to create categories through condensation and interpretation. The two main categories that emerged were 'professional role' and 'teamwork'. These were analysed and compared according to the two first meeting in the two focus groups. Results and discussion: The results indicate different levels of motivation and understanding regarding role transformation processes. The realization of transdisciplinary collaboration is dependent upon the professionals' mutual reliance. The professionals' participation is affected by stereotypes and differences in their sense of belonging to a certain network, and thus their identity transformation seems to be strongly affected. To encourage the use of integrated solutions in mental health care, the professionals' preference for teamwork, the importance of familiarity with each other and knowledge of cultural barriers should be addressed.
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| 12. |
- Jawak, Shridhar D., et al.
(författare)
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SIOS's Earth Observation (EO), Remote Sensing (RS), and Operational Activities in Response to COVID-19
- 2021
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Ingår i: Remote Sensing. - : MDPI. - 2072-4292. ; 13:4
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Tidskriftsartikel (refereegranskat)abstract
- Svalbard Integrated Arctic Earth Observing System (SIOS) is an international partnership of research institutions studying the environment and climate in and around Svalbard. SIOS is developing an efficient observing system, where researchers share technology, experience, and data, work together to close knowledge gaps, and decrease the environmental footprint of science. SIOS maintains and facilitates various scientific activities such as the State of the Environmental Science in Svalbard (SESS) report, international access to research infrastructure in Svalbard, Earth observation and remote sensing services, training courses for the Arctic science community, and open access to data. This perspective paper highlights the activities of SIOS Knowledge Centre, the central hub of SIOS, and the SIOS Remote Sensing Working Group (RSWG) in response to the unprecedented situation imposed by the global pandemic coronavirus (SARS-CoV-2) disease 2019 (COVID-19). The pandemic has affected Svalbard research in several ways. When Norway declared a nationwide lockdown to decrease the rate of spread of the COVID-19 in the community, even more strict measures were taken to protect the Svalbard community from the potential spread of the disease. Due to the lockdown, travel restrictions, and quarantine regulations declared by many nations, most physical meetings, training courses, conferences, and workshops worldwide were cancelled by the first week of March 2020. The resumption of physical scientific meetings is still uncertain in the foreseeable future. Additionally, field campaigns to polar regions, including Svalbard, were and remain severely affected. In response to this changing situation, SIOS initiated several operational activities suitable to mitigate the new challenges resulting from the pandemic. This article provides an extensive overview of SIOS's Earth observation (EO), remote sensing (RS) and other operational activities strengthened and developed in response to COVID-19 to support the Svalbard scientific community in times of cancelled/postponed field campaigns in Svalbard. These include (1) an initiative to patch up field data (in situ) with RS observations, (2) a logistics sharing notice board for effective coordinating field activities in the pandemic times, (3) a monthly webinar series and panel discussion on EO talks, (4) an online conference on EO and RS, (5) the SIOS's special issue in the Remote Sensing (MDPI) journal, (6) the conversion of a terrestrial remote sensing training course into an online edition, and (7) the announcement of opportunity (AO) in airborne remote sensing for filling the data gaps using aerial imagery and hyperspectral data. As SIOS is a consortium of 24 research institutions from 9 nations, this paper also presents an extensive overview of the activities from a few research institutes in pandemic times and highlights our upcoming activities for the next year 2021. Finally, we provide a critical perspective on our overall response, possible broader impacts, relevance to other observing systems, and future directions. We hope that our practical services, experiences, and activities implemented in these difficult times will motivate other similar monitoring programs and observing systems when responding to future challenging situations. With a broad scientific audience in mind, we present our perspective paper on activities in Svalbard as a case study.
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| 13. |
- Jelenkovic, Aline, et al.
(författare)
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Zygosity Differences in Height and Body Mass Index of Twins From Infancy to Old Age : A Study of the CODATwins Project
- 2015
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Ingår i: Twin Research and Human Genetics. - : Cambridge University Press. - 1832-4274 .- 1839-2628. ; 18:5, s. 557-570
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Tidskriftsartikel (refereegranskat)abstract
- A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m(2) in childhood and adolescence and up to 0.2 kg/m(2) in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
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| 14. |
- Jonsson, Niklas, et al.
(författare)
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Calprotectin as an early biomarker of bacterial infections in critically ill patients : an exploratory cohort assessment
- 2017
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Ingår i: Criminology & Public Policy. - 1538-6473 .- 1745-9133. ; 19:3, s. 205-213
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Calprotectin is the most abundant protein in the cytosolic fraction of neutrophils, and neutrophil degranulation is a major response to bacterial infections.OBJECTIVES: To assess the value of plasma calprotectin as an early marker of bacterial infections in critically ill patients and compare it with the corresponding values for procalcitonin (PCT), C-reactive protein (CRP) and white blood cell count (WBC).METHODS: We measured daily plasma calprotectin levels in 110 intensive care unit patients using a newly developed turbidimetric assay run on clinical chemistry analysers. The likelihood of infection was determined according to the International Sepsis Forum criteria.RESULTS: Overall, 58 patients (52.7%) developed a suspected or confirmed bacterial infection. Plasma calprotectin predicted such infections within 24 hours with an area under the receiver operating characteristics curve (ROC area) of 0.78 (95% CI, 0.68-0.89). The ROC area for calprotectin was significantly greater than the corresponding ROC areas for WBC (P < 0.001) and PCT (P = 0.02) but only marginally better than the ROC area for CRP (0.71; 95% CI, 0.68-0.89).CONCLUSION: Plasma calprotectin appears to be a useful early marker of bacterial infections in critically ill patients, with better predictive characteristics than WBC and PCT.
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| 15. |
- Kjaerner-Semb, Erik, et al.
(författare)
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Comparison of anadromous and landlocked Atlantic salmon genomes reveals signatures of parallel and relaxed selection across the Northern Hemisphere
- 2021
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Ingår i: Evolutionary Applications. - : John Wiley & Sons. - 1752-4571. ; 14:2, s. 446-461
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Tidskriftsartikel (refereegranskat)abstract
- Most Atlantic salmon (Salmo salarL.) populations follow an anadromous life cycle, spending early life in freshwater, migrating to the sea for feeding, and returning to rivers to spawn. At the end of the last ice age similar to 10,000 years ago, several populations of Atlantic salmon became landlocked. Comparing their genomes to their anadromous counterparts can help identify genetic variation related to either freshwater residency or anadromy. The objective of this study was to identify consistently divergent loci between anadromous and landlocked Atlantic salmon strains throughout their geographical distribution, with the long-term aim of identifying traits relevant for salmon aquaculture, including fresh and seawater growth, omega-3 metabolism, smoltification, and disease resistance. We used a Pool-seq approach (n = 10-40 individuals per population) to sequence the genomes of twelve anadromous and six landlocked Atlantic salmon populations covering a large part of the Northern Hemisphere and conducted a genomewide association study to identify genomic regions having been under different selection pressure in landlocked and anadromous strains. A total of 28 genomic regions were identified and includedcadm1on Chr 13 andppargc1aon Chr 18. Seven of the regions additionally displayed consistently reduced heterozygosity in fish obtained from landlocked populations, including the genes gpr132, cdca4, and sertad2 on Chr 15. We also found 16 regions, includingigf1on Chr 17, which consistently display reduced heterozygosity in the anadromous populations compared to the freshwater populations, indicating relaxed selection on traits associated with anadromy in landlocked salmon. In conclusion, we have identified 37 regions which may harbor genetic variation relevant for improving fish welfare and quality in the salmon farming industry and for understanding life-history traits in fish.
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| 16. |
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| 17. |
- Mandic-Havelka, Aleksandra, et al.
(författare)
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Turbidimetric Determination of Fecal Calprotectin Using Two Table Top Chemistry Analyzers : Mindray BS-200E and Cobas® c111
- 2017
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Ingår i: Clinical Laboratory. - 1433-6510. ; 63:5, s. 907-913
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Fecal calprotectin assays are widely used in diagnosis and monitoring of inflammatory bowel disease (IBD) in patients with suspected IBD. The most frequently used technique is ELISA and microtiter plates. Turbidimetric assays for analysis of fecal calprotectin can significantly reduce turnaround time. Many laboratories may be reluctant to run fecal samples on their large chemistry analyzers. The aim of this study was to evaluate fecal calprotectin particle enhanced turbidimetric immunoassay (PETIA) on smaller chemistry analyzers that could be dedicated for fecal samples.METHODS: The BÜHLMANN fCAL® turbo assay was validated on two table top chemistry analyzers, Mindray BS-200E and cobas® c111.RESULTS: The assay was linear in the range between 20 and 1,900 µg/g with a limit of quantification around 20 µg/g on both instruments. The total coefficient of variation was < 7% in the range between 50 and 1,300 µg/g on both instruments. No antigen excess hook effect was observed up to 18,000 µg/g on the Mindray BS-200E and up to 20,000 µg/g on cobas® c111. The BÜHLMANN fCAL® turbo assay showed a high correlation with the BÜHLMANN fCAL® ELISA.CONCLUSIONS: Running the BÜHLMANN fCAL® turbo on Mindray BS-200E or cobas® c111 chemistry analyzers can provide rapid test results without exposing large routine chemistry analyzers to stool samples.
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| 18. |
- Ndjole, Annaby Moussa, et al.
(författare)
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Determination of cerebrospinal fluid cystatin C on Architect ci8200
- 2010
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Ingår i: JIM - Journal of Immunological Methods. - : Elsevier BV. - 0022-1759 .- 1872-7905. ; 360:1-2, s. 84-88
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Human cystatin C is a cysteine protease inhibitor produced by all nucleated cells in the body and the protein is present in all body fluids. The concentration in cerebrospinal fluid (CSF) is considerably higher than in plasma. Cystatin C levels seem to influence the development of Alzheimer disease (AD) and low levels in the brain are associated with an increased risk for AD. The aim of this study was to develop a high throughput assay for the quantification of cystatin C in CSF. METHODS: Antigen excess, imprecision, interference, linearity, recovery, sample stability and reference values were evaluated on Architect ci8200 (Abbott Laboratories, Abbott Park, IL, USA). RESULTS: The assay had an antigen-excess limit at 23 mg/L and was linear over the range of 0.84 to 8.33 mg/L. Results > 8.33 mg/L were automatically rerun in a higher dilution. Within-run coefficient of variation (CV) was 1.71, 1.10 and 0.79%, between day CV was 1.71, 0.39 and 1.45%, between-run CV was 0.58, 0.66 and 0.48%, and total CV was 2.49, 1.34 and 1.72% at cystatin C concentrations of 1.39, 3.17 and 6.28 mg/L, respectively. The recovery was 97-102%. No interference at a 7.5% deviation level was observed for 8.5 g/L of hemoglobin or 800 mg/L (1368 micromol/L) of bilirubin. Reference values for cystatin C in cerebrospinal fluid obtained with this method were 2.42-14.33 mg/L.
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| 19. |
- Nilsen, Tom, et al.
(författare)
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A new turbidimetric immunoassay for serum calprotectin for fully automatized clinical analysers
- 2015
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Ingår i: Journal of Inflammation. - : Springer Science and Business Media LLC. - 1476-9255. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Serum and plasma calprotectin concentration is shown to be elevated when neutrophils are activated, and may therefore be used as a marker for inflammatory diseases. A serum calprotectin immunoassay was developed based on calprotectin values observed in samples from the intensive care unit. The polyclonal avian antibodies were raised and affinity purified with calprotectin antigens. The performance was tested and it was observed that the assay was linear in the range 0.3-24.7 mg/L, the limit of quantitation was observed to be lower than 0.3 mg/L, no antigen excess was observed up to 54 mg/L, all CVs were lower than 1.8 % in the precision study, the calibration curve stability was longer than 6 weeks, and there was no significant interference detected for haemoglobin, intralipid or bilirubin. The serum calprotectin immunoassay presented in this paper performs well within the criteria carefully set from the limited clinical experience obtained in both serum and plasma. In addition it is commutable with Bühlmann MRP8/14 ELISA.
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| 20. |
- Nilsen, Tom, et al.
(författare)
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A novel turbidimetric immunoassay for fecal calprotectin optimized for routine chemistry analyzers
- 2017
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Ingår i: Journal of clinical laboratory analysis (Print). - : Wiley. - 0887-8013 .- 1098-2825. ; 31:4
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Fecal calprotectin assays are widely used to exclude inflammatory bowel disease (IBD) in patients with suspected IBD. A problem with the fecal calprotectin assays is the rather long test-turnaround times. A particle enhanced turbidimetric immunoassays (PETIA) for fecal calprotectin would reduce test-turnaround times and would permit more laboratories to perform the measurements. The aim of this study was to evaluate a new feces calprotectin PETIA.METHOD: Using routine fecal samples the feces calprotectin PETIA was validated on two chemistry analyzers, Mindray BS-380 and Cobas 501.RESULTS: The assay is linear in the range 11-2000 μg/g, with a limit of quantitation of approximately 10 μg/g. No antigen excess hook effect was observed up to 10 000-15 000 μg/g depending on the instrument used. The turbidimetric method showed a good agreement with the Bühlmann ELISA. The total coefficient of variation was 3%-8% in the 50-100 μg/g range.CONCLUSION: The fecal calprotectin PETIA, fCal Turbo, is well suited for rapid analysis of fecal calprotectin on Mindray BS-380 or Cobas 501 clinical chemistry analyzers. The test results are commutable with Bühlmann fecal MRP8/14 ELISA.
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| 21. |
- Nilsen, Tom
(författare)
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Avian antibodies applied in particle enhanced turbidimetric immunoassay : Developement of serum/plasma calprotectin immunoassay and its clinical performance as a marker for bacterial infections
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Calprotectin is a cytosolic protein in the granulocytes, consisting of S100A8 and S100A9. On the site of inflammation, the neutrophils release the cytosol as an inflammatory response. The circulating calprotectin concentration increases and can therefore be used as marker for neutrophil activation and inflammation.To raise specific antibodies, it is crucial to immunize with pure calprotectin antigen. We purified calprotectin from human granulocytes by ion-exchange chromatography, dialysed it towards saline and concentrated it to required levels, suited for immunisation of the hens. The purified antigen solutions were assigned concentration values by the Biuret method and the purity was checked by SDS PAGE and size exclusion chromatography. The yield was approximately 2 mg purified antigens per unit of 450 ml blood.A prototype calprotectin particle enhanced turbidimetric immunoassay was developed from the purified antigen and the affinity purified antibodies. The antigen was spiked into PBS to prepare calibrators and controls. The antibodies were coated to latex particles to prepare immunoparticles. The performance of the immunoassay was technically tested on a clinical chemistry analyser. LoQ, antigen excess, linearity, precision and calibration stability met the pre-set criteria.In the production process of immunoparticles there are several factors affecting the performance of the assay. Investigating eight factors applying a Taguchi L12 screening, we experienced that conductivity and pH of conjugate buffer, coating grade and conductivity of dialysis buffer II affected the sensitivity and antigen excess the most.The assay was used to measure clinical samples. Serum samples from elderly people aged 70+ were collected. Only patients with no infections were included to establish a reference interval for this patient group. The reference interval in serum was 0.3 mg/L to 2.5 mg/L for both genders. Furthermore, the plasma calprotectin immunoassay was tested clinically on critically ill patients to assess the ability of plasma calprotectin as an early marker for detection of bacterial infections. It showed promising results. Calprotectin was a better predictive marker for sepsis than procalcitonin and white blood cell count. Because some patients with an inflammation have low numbers of granulocytes, we examined the correlation between white blood cell count and the calprotectin levels in a group of patients with an inflammation. There was a weak correlation between the number of white blood cells and calprotectin concentration.
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| 22. |
- Nilsen, Tom, et al.
(författare)
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Extraction,isolation, and concentration of calprotectin antigen (S100A8/S100A9) fromgranulocytes
- 2018
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Ingår i: Health Science Reports. - : Wiley-Blackwell Publishing Inc.. - 2398-8835. ; 1:5
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Tidskriftsartikel (refereegranskat)abstract
- Background: Calprotectin is a promising biomarker for granulocyte activation. It is mainly measured in faeces as a marker for inflammatory bowel disease. A limitation is that there is no widely accepted calibrator.Aim: To establish a method for purification of calprotectin from human granulocytes that is easily reproducible, reliable, and could contribute to a better agreement between different calprotectin methods.Methods and results: Calprotectin was purified from granulocyte extracts using ion‐exchange chromatography. The granulocytes were separated from blood bags. The purity was analysed by analysing pixel density of a picture of the sodium dodecyl sulfate polyacrylamide gel electrophoresis and by size exclusion chromatography. The calprotectin concentration of the pure antigen solution was determined using Biuret method. The purity was >95% for 3 preparations, and their concentrations were 1079, 1080, and 1813 mg/L.Conclusion: It is possible to reproducibly prepare highly purified calprotectin antigen from human granulocytes. The preparations can be used for preparing calibrators, controls for immunological calprotectin assays, and immunisation for raising antibodies against human calprotectin in hens.
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| 23. |
- Nilsen, Tom, et al.
(författare)
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Influence of 8 parameters when coating avian calprotectin antibodies to latex particles
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Aim: To find the parameters affecting sensitivity and security zone in the preparation process of immunoparticles with avian antibodies for use in particle enhanced turbidimetric immunoassays. Method: 12 combinations of 8 parameters were tested in the preparation process of the immunoparticles. The study was designed according to Taguchi L12 screening method and analysed using DOE KISS PRO XL. Results/Conclusion: The parameters affecting the sensitivity and security zone the most were conductivity of the conjugate buffer, coating grade and pH of the conjugate buffer.
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| 24. |
- Nilsen, Tom O, et al.
(författare)
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Differential expression of gill Na+,K+-ATPase alpha- and beta-subunits, Na+,K+,2Cl- cotransporter and CFTR anion channel in juvenile anadromous and landlocked Atlantic salmon Salmo salar.
- 2007
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Ingår i: The Journal of experimental biology. - : The Company of Biologists. - 0022-0949 .- 1477-9145. ; 210:Pt 16, s. 2885-96
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Tidskriftsartikel (refereegranskat)abstract
- This study examines changes in gill Na(+),K(+)-ATPase (NKA) alpha- and beta-subunit isoforms, Na(+),K(+),2Cl(-) cotransporter (NKCC) and cystic fibrosis transmembrane conductance regulator (CFTR I and II) in anadromous and landlocked strains of Atlantic salmon during parr-smolt transformation, and after seawater (SW) transfer in May/June. Gill NKA activity increased from February through April, May and June among both strains in freshwater (FW), with peak enzyme activity in the landlocked salmon being 50% below that of the anadromous fish in May and June. Gill NKA-alpha1b, -alpha3, -beta(1) and NKCC mRNA levels in anadromous salmon increased transiently, reaching peak levels in smolts in April/May, whereas no similar smolt-related upregulation of these transcripts occurred in juvenile landlocked salmon. Gill NKA-alpha1a mRNA decreased significantly in anadromous salmon from February through June, whereas alpha1a levels in landlocked salmon, after an initial decrease in April, remained significantly higher than those of the anadromous smolts in May and June. Following SW transfer, gill NKA-alpha1b and NKCC mRNA increased in both strains, whereas NKA-alpha1a decreased. Both strains exhibited a transient increase in gill NKA alpha-protein abundance, with peak levels in May. Gill alpha-protein abundance was lower in SW than corresponding FW values in June. Gill NKCC protein abundance increased transiently in anadromous fish, with peak levels in May, whereas a slight increase was observed in landlocked salmon in May, increasing to peak levels in June. Gill CFTR I mRNA levels increased significantly from February to April in both strains, followed by a slight, though not significant increase in May and June. CFTR I mRNA levels were significantly lower in landlocked than anadromous salmon in April/June. Gill CFTR II mRNA levels did not change significantly in either strain. Our findings demonstrates that differential expression of gill NKA-alpha1a, -alpha1b and -alpha3 isoforms may be important for potential functional differences in NKA, both during preparatory development and during salinity adjustments in salmon. Furthermore, landlocked salmon have lost some of the unique preparatory upregulation of gill NKA, NKCC and, to some extent, CFTR anion channel associated with the development of hypo-osmoregulatory ability in anadromous salmon.
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| 25. |
- Nilsen, Tom Ole, et al.
(författare)
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EFFECTS OF ANDROGENS AND CORTISOL ON GILL ION TRANSPORTERS AND OMSMOREGULATORY CAPACITY IN ATLANTIC SALMON (SALMO SALAR)
- 2014
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Ingår i: ICBF 2014, Edinburgh.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Sex steroids have been reported to compromise ion homeostasis in teleosts, yet there is limited and somewhat contradicting knowledge about the mechanisms through which androgens impact osmoregulatory capacity in salmonids. Immature Atlantic salmon post-smolts in seawater (SW) were injected with 11-ketoandrostenedione (OA; 25 µg/g BW), cortisol (F; 25 µg/g BW), F+OA (25 µg/g BW) and sham control (CON). After 8 days treatment, androgen treated fishdemonstrated a striking transcriptional increase in freshwater (FW)-type of ion transporters (NKA α1a ) , concurrent with no apparent ion perturbations, or down regulation of SW gill ion-transporters (NKA α1b). F treated post-smolts displayed increased gill NKA α1a transcription, with an additive effect of F+OA.. Moreover, F also resulted in decreased transcription of NKA α1b whilst fish treated with combinations of F and OA experienced severe ion perturbations and mortalities in SW, while no mortality occurred when only F was administered. Our findings suggests that androgens have, either directly or indirectly, a role in remodelling the gill epithelia for FW entry, rather than leading to osmoregulatory dysfunction in SW acclimated post-smolts. Moreover, maturing post-smolts may be sensitive to stress since combinations of elevated androgens and cortisol levels may have detrimental effects on homeostasis and fish welfare.
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| 26. |
- Nilsen, Tom O, et al.
(författare)
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Endocrine systems in juvenile anadromous and landlocked Atlantic salmon (Salmo salar): seasonal development and seawater acclimation.
- 2008
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Ingår i: General and comparative endocrinology. - : Elsevier BV. - 0016-6480. ; 155:3, s. 762-72
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Tidskriftsartikel (refereegranskat)abstract
- The present study compares developmental changes in plasma levels of growth hormone (GH), insulin-like growth factor I (IGF-I) and cortisol, and mRNA levels of their receptors and the prolactin receptor (PRLR) in the gill of anadromous and landlocked Atlantic salmon during the spring parr-smolt transformation (smoltification) period and following four days and one month seawater (SW) acclimation. Plasma GH and gill GH receptor (GHR) mRNA levels increased continuously during the spring smoltification period in the anadromous, but not in landlocked salmon. There were no differences in plasma IGF-I levels between strains, or any increase during smoltification. Gill IGF-I and IGF-I receptor (IGF-IR) mRNA levels increased in anadromous salmon during smoltification, with no changes observed in landlocked fish. Gill PRLR mRNA levels remained stable in both strains during spring. Plasma cortisol levels in anadromous salmon increased 5-fold in May and June, but not in landlocked salmon. Gill glucocorticoid receptor (GR) mRNA levels were elevated in both strains at the time of peak smoltification in anadromous salmon, while mineralocorticoid receptor (MR) mRNA levels remained stable. Only anadromous salmon showed an increase of gill 11beta-hydroxysteroid dehydrogenase type-2 (11beta-HSD2) mRNA levels in May. GH and gill GHR mRNA levels increased in both strains following four days of SW exposure in mid-May, whereas only the anadromous salmon displayed elevated plasma GH and GHR mRNA after one month in SW. Plasma IGF-I increased after four days in SW in both strains, decreasing in both strains after one month in SW. Gill IGF-I mRNA levels were only increased in landlocked salmon after 4days in SW. Gill IGF-IR mRNA levels in SW did not differ from FW levels in either strain. Gill PRLR mRNA did not change after four days of SW exposure, and decreased in both strains after one month in SW. Plasma cortisol levels did not change following SW exposure in either strain. Gill GR, 11beta-HSD2 and MR mRNA levels increased after four days in SW in both strains, whereas only the anadromous strain maintained elevated gill GR and 11beta-HSD2 mRNA levels after one month in SW. The results indicate that hormones and receptors of the GH and cortisol axes are present at significantly lower levels during spring development and SW acclimation in landlocked relative to anadromous salmon. These findings suggest that attenuation of GH and cortisol axes may, at least partially, result in reduced preparatory upregulation of key gill ion-secretory proteins, possibly a result of reduced selection pressure for marine adaptations in landlocked salmon.
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| 27. |
- Nilsen, Tom, et al.
(författare)
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Serum calprotectin levels in elderly males and females without bacterial or viral infections
- 2014
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Ingår i: Clinical Biochemistry. - : Elsevier BV. - 0009-9120 .- 1873-2933. ; 47:12, s. 1065-1068
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: Calprotectin is released from activated leukocytes and calprotectin can thus be used as a marker for leukocyte activation. Faeces calprotectin is not only used as a marker for inflammatory bowel disease but can also be used to detect leukocyte activation in other body fluids. The aim of the present study was to study serum calprotectin levels in non-infected elderly individuals to establish reference intervals for the marker.METHODS: Serum calprotectin was analyzed by immunoturbidimetry in 75year old females and males without known infections. Individuals with CRP>20mg/L were excluded as this could indicate a subclinical infection. The calprotectin levels in the remaining 713 individuals were used to calculate reference values for this population. The Spearman rank correlations between calprotectin and 27 other laboratory biomarkers were also investigated.RESULTS: There was a strong positive Spearman rank correlation between calprotectin and CRP (p<0.000001) and alkaline phosphatase (p<0.000001). There were also significant negative correlations between calprotectin and ApoA1 and direct HDL-cholesterol.CONCLUSIONS: The reference interval for serum-calprotectin for all study subjects was 0.3-2.6mg/L. Leukocyte alkaline phosphatase contributes to serum alkaline phosphatase levels.
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| 28. |
- Ronnestad, Ivar, et al.
(författare)
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Leptin and leptin receptor genes in Atlantic salmon: Cloning, phylogeny, tissue distribution and expression correlated to long-term feeding status
- 2010
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Ingår i: GENERAL AND COMPARATIVE ENDOCRINOLOGY. - 0016-6480. ; 168:1, s. 55-70
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Tidskriftsartikel (refereegranskat)abstract
- The present study reports the complete coding sequences for two paralogues for leptin (sLepA1 and sLepA2) and leptin receptor (sLepR) in Atlantic salmon. The deduced 171-amino acid (aa) sequence of sLepA1 and 175 aa sequence for sLepA2 shows 71.6% identity to each other and clusters phylogenetically with teleost Lep type A, with 22.4% and 24.1% identity to human Lep. Both sLep proteins are predicted to consist of four helixes showing strong conservation of tertiary structure with other vertebrates. The highest mRNA levels for sLepA1 in fed fish (satiation ration = 100%) were observed in the brain, white muscle, liver, and ovaries. In most tissues sLepA2 generally had a lower expression than sLepA1 except for the gastrointestinal tract (stomach and mid-gut) and kidney. Only one leptin receptor ortholog was identified and it shares 24.2% aa sequence similarity with human LepR, with stretches of highest sequence similarity corresponding to domains considered important for LepR signaling. The sLepR was abundantly expressed in the ovary, and was also high in the brain, pituitary, eye, gill, skin, visceral adipose tissue, belly flap, red muscle, kidney, and testis. Fish reared on a rationed feeding regime (60% of satiation) for 10 months grew less than control (100%) and tended to have a lower sLepA1 mRNA expression in the fat-depositing tissues visceral adipose tissue (p < 0.05) and white muscle (n.s.). sLepA2 mRNA levels was very low in these tissues and feeding regime tended to affect its expression in an opposite manner. Expression in liver differed from that of the other tissues with a higher sLepA2 mRNA in the feed-rationed group (p < 0.01). Plasma levels of sLep did not differ between fish fed restricted and full feeding regimes. No difference in brain sLepR mRNA levels was observed between fish fed reduced and full feeding regimes. This study in part supports that sLepA1 is involved in signaling the energy status in fat-depositing tissues in line with the mammalian model, whereas sLepA2 may possibly play important roles in the digestive tract and liver. At present, data on Lep in teleosts are too scarce to allow generalization about how the Lep system is influenced by tissue-specific energy status and, in turn, may regulate functions related to feed intake, growth, and adiposity in fish. In tetraploid species like Atlantic salmon, different Lep paralogues seems to serve different physiological roles.
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| 29. |
- Silventoinen, Karri, et al.
(författare)
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The CODATwins Project : The Cohort Description of Collaborative Project of Development of Anthropometrical Measures in Twins to Study Macro-Environmental Variation in Genetic and Environmental Effects on Anthropometric Traits
- 2015
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Ingår i: Twin Research and Human Genetics. - : Cambridge University Press. - 1832-4274 .- 1839-2628. ; 18:4
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Tidskriftsartikel (refereegranskat)abstract
- For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations. Opportunities to address this question have increased recently because of the establishment of many new twin cohorts and the increasing accumulation of data in established twin cohorts. We started a new research project to analyze systematically (1) the variation of heritability estimates of height, BMI and their trajectories over the life course between birth cohorts, ethnicities and countries, and (2) to study the effects of birth-related factors, education and smoking on these anthropometric traits and whether these effects vary between twin cohorts. We identified 67 twin projects, including both monozygotic (MZ) and dizygotic (DZ) twins, using various sources. We asked for individual level data on height and weight including repeated measurements, birth related traits, background variables, education and smoking. By the end of 2014, 48 projects participated. Together, we have 893,458 height and weight measures (52% females) from 434,723 twin individuals, including 201,192 complete twin pairs (40% monozygotic, 40% same-sex dizygotic and 20% opposite-sex dizygotic) representing 22 countries. This project demonstrates that large-scale international twin studies are feasible and can promote the use of existing data for novel research purposes.
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| 30. |
- Simm, Mikael, et al.
(författare)
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Performance of plasma calprotectin as a biomarker of early sepsis : a pilot study
- 2016
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Ingår i: Biomarkers in Medicine. - : Future Medicine Ltd. - 1752-0363 .- 1752-0371. ; 10:8, s. 811-818
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Tidskriftsartikel (refereegranskat)abstract
- AIM: To determine the performance of plasma calprotectin as a marker of sepsis on intensive care unit (ICU) admission and as a marker of mortality day 30 post-ICU admission.MATERIALS & METHODS: Consecutive ICU patients were allocated to: sepsis (n = 15), postoperative inflammation (n = 23) and intoxication without inflammation (n = 7) groups.RESULTS: Calprotectin was 4.3 (2.6-8.2; mg/l; median [interquartile range]) in the sepsis, 2.8 (1.6-4.4) in the postoperative and 0.7 (0.4-1.6) in the intoxication groups. Area under the receiver operating characteristic curve for sepsis versus intoxication group was: 0.95, for sepsis versus postoperative groups: 0.65 and for survivors versus nonsurvivors: 0.70.CONCLUSION: Calprotectin was a sensitive marker of systemic inflammation, is a potential sepsis marker and performed well as mortality predictor in this pilot study.
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| 31. |
- Stefansson, S. O., et al.
(författare)
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Molecular mechanisms of continuous light inhibition of Atlantic salmon parr–smolt transformation
- 2007
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Ingår i: Aquaculture. - : Elsevier BV. - 0044-8486. ; 273:2-3, s. 235-245
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Tidskriftsartikel (refereegranskat)abstract
- Atlantic salmon (Salmo salar) rely on changes in photoperiod for the synchronization of the developmental events constituting the parr–smolt transformation. In the absence of photoperiod cues, parr–smolt transformation is incomplete, and such ‘pseudo-smolts’ normally fail to adapt to seawater. The present study addresses the endocrine and molecular mechanisms controlling the development of hypo-osmoregulatory ability and how artificial photoperiod can disrupt these changes. Juvenile Atlantic salmon reared under constant light (LL) from first feeding, were separated into two groups, and exposed to either LL or simulated natural photoperiod (LDN) from October, eight months prior to the expected completion of smoltification. Juveniles reared on LL grew well, but failed to show the smolt-related reduction in condition factor in spring. Gill mRNA levels of Na+, K+–ATPase (NKA) isoform α1a decreased in LDN fish through completion of parr–smolt transformation, while levels remained unchanged in the LL group. In contrast, α1b expression increased 6-fold in the LDN group between February and May, again with no change in the LL group. Further, Na+, K+, 2Cl− co-transporter (NKCC) showed a transient increase in expression in smolts on LDN between February and May, while no changes in mRNA levels were seen in juveniles under LL. Consequently, gill NKA activity and NKA α and NKCC protein abundance were significantly lower in juveniles on LL than in smolts on LDN. LL fish in spring had lower circulating levels of thyroid hormones (THs), growth hormone (GH) and cortisol. Gill GH-receptor mRNA levels, determined by quantitative PCR, were less than 50% of controls. In contrast, circulating levels of IGF-1 and gill IGF-1 receptor expression, were comparable to controls. Our findings show that continuous light prevents the completion of parr–smolt transformation at a very basic level, disrupting the natural up-regulation of key elements of the endocrine system involved in the regulation of the parr–smolt transformation, and consequently inhibiting the smoltification-related increase in expression, abundance and activity of gill ion transport proteins.
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| 32. |
- Sunde, Kathrin, et al.
(författare)
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Performance characteristics of a cystatin C immunoassay with avian antibodies
- 2007
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Ingår i: Upsala Journal of Medical Sciences. - 0300-9734 .- 2000-1967. ; 112:1, s. 21-37
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Tidskriftsartikel (refereegranskat)abstract
- Background: A new particle-enhanced turbidimetric immunoassay (PETIA) with avian antibodies for measuring serum/plasma cystatin C has been developed. The performance characteristics of the assay are described. Methods: Measurements were performed on a Roche Modular P and on an Abbott Architect ci8200 using Gentian cystatin C immunoassay. Results: Measuring range was 0.3 - 8.0 mg/ L. Reference range was 0.57 - 1.09 mg/ L. Total analysis time was 10 minutes. Linearity was absolute over the whole assay range. Recovery of samples and controls was within 98.6 - 109.4%. Total imprecision CV, measured over 20days with two lots, was <= 4.2%. Comparision with a particle enhanced nephelometric cystatin C immunoassay (PENIA) by linear regression resulted in a slope within 0.97 - 1.02 and intercept within +/- 0.05 mg/ L. Interference studies with drugs, anticoagulants, intralipid (<= 11g/L), triglycerides (<= 14 g/L) and bilirubin (<= 420 mg/L) showed no significant interference. Due to the use of avain antibodies, no interference with rheumatoid factor was observed. No carry-over was detected. Lower detection limit and lower quantification limit (CV <= 6%) were both below 0.33 mg/L, which is less than the lowest standard. Sample stability was up to one month at 2 - 8 degrees C. Stability of the reagents at 2 - 8 degrees C was estimated to be 24 months. Stability of the reagents in use was minimum 9 weeks. Conclusions: Gentian cystatin C PETIA is shown to have excellent performance between methods. Interference results are improved due to avian antibodies and a broader span of the calibration curve. Avian antibodies are also known to have better immune response than mammalian antibodies towards mammalian antigens.
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| 33. |
- Sundh, Henrik, 1976, et al.
(författare)
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NUTRIENT ABSORPTION IN THE ATLANTIC SALMON (SALMO SALAR L.) INTESTINE IS AFFECTED BY ENVIRONMENTAL SALINITY
- 2014
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Ingår i: ICBF 2014, Edinburgh.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Na+/K+-ATPases (NKA) located in the basolateral membrane of the intestinal absorptive cells (enterocytes) are the main driving force for both ion-coupled intestinal fluid transport and nutrient absorption in Atlantic salmon in seawater. It is hypothesized that a decreased need for osmoregulation in brackish water may be beneficial for the nutrient uptake and thereby the growth of the fish. Atlantic salmon post-smolts were acclimated to freshwater (FW), 12, 22 and 34 ppt seawater (SW) for several months. The intestinal nutrient transport (L-lysine and D-glucose) was measured in Ussing chambers and separate fish were used for intestinal mRNA expression of selected ion and nutrient transporters. No differences were found in mRNA levels of the NKA-α1c, NKCC2 co-transporter or SGLT-1 in relation to salinity, whereas the specific high-affinity low capacity Na+-coupled nutrient transport was significantly higher in FW and 22 ppt as compared to the 34 ppt group. The results suggest an allocation of the electrochemical gradient towards ion driven fluid transport in full strength SW.
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| 34. |
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| 35. |
- Takvam, Marius, et al.
(författare)
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New wine in old bottles: Modification of the Na+/K+-ATPase enzyme activity assay and its application in salmonid aquaculture
- 2023
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Ingår i: REVIEWS IN AQUACULTURE. - 1753-5123 .- 1753-5131.
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Forskningsöversikt (refereegranskat)abstract
- The Na+, K+ ATPase (NKA) enzyme is important to generate the transmembrane ion gradient in the gills, intestine, and kidneys, hence, is vital for secondary transport of fluids and different solutes in teleosts. Gill NKA enzyme activity is often used as a proxy for parr-smolt transformation (PST) during which anadromous salmonids prepare for seawater (SW). Increased intensification and production of larger smolts in modern salmonid aquaculture has resulted in reports of gill NKA activity being less reliable as a proxy for smolt quality. Consequently, changes in mRNA nka-alpha 1b/alpha 1a ratios in gills are increasingly used as indicators of PST. However, nka isoform mRNA abundance may not reflect translation into the functional protein, nor the activity of the mature enzyme. This may limit the predictive power of molecular markers under certain environmental conditions, rearing regimes and biological scenarios. During PST, the osmoregulatory transformations necessary for SW tolerance and survival does not only occur in the gills. Equally important are the changes in ion transporting activities, including NKA activity, in the intestine and kidneys. However, to our knowledge, there are no previous studies addressing the timing and concurrent changes in NKA activity in the three osmoregulatory tissue during PST. Here we present modifications and optimization of the NKA enzyme activity protocols for gill, intestinal and kidney tissue and outline how to best utilize NKA activity measurements as part of a more holistic approach to evaluate overall smolt quality in modern aquaculture.
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| 36. |
- Vindas, Marco A., et al.
(författare)
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How do individuals cope with stress? : Behavioural, physiological and neuronal differences between proactive and reactive coping styles in fish
- 2017
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Ingår i: Journal of Experimental Biology. - : The Company of Biologists. - 0022-0949 .- 1477-9145. ; 220:8, s. 1524-1532
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Tidskriftsartikel (refereegranskat)abstract
- Despite the use of fish models to study human mental disorders and dysfunctions, knowledge of regional telencephalic responses in non-mammalian vertebrates expressing alternative stress coping styles is poor. As perception of salient stimuli associated with stress coping in mammals is mainly under forebrain limbic control, we tested region-specific forebrain neural (i.e. mRNA abundance and monoamine neurochemistry) and endocrine responses under basal and acute stress conditions for previously characterised proactive and reactive Atlantic salmon. Reactive fish showed a higher degree of the neurogenesis marker proliferating cell nuclear antigen (pcna) and dopamine activity under basal conditions in the proposed hippocampus homologue (Dl) and higher post-stress plasma cortisol levels. Proactive fish displayed higher post-stress serotonergic signalling (i.e. higher serotonergic activity and expression of the 5-HT1A receptor) in the proposed amygdala homologue (Dm), increased expression of the neuroplasticity marker brain-derived neurotropic factor (bdnf) in both Dl and the lateral septum homologue (Vv), as well as increased expression of the corticotropin releasing factor 1 (crf(1)) receptor in the Dl, in line with active coping neuro-profiles reported in the mammalian literature. We present novel evidence of proposed functional equivalences in the fish forebrain with mammalian limbic structures.
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| 37. |
- Aad, G., et al.
(författare)
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- 2012
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swepub:Mat__t (refereegranskat)
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