| 1. |
- Backström, Tobias, et al.
(författare)
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CRF and urotensin I effects on aggression and anxiety-like behavior in rainbow trout
- 2011
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Ingår i: Journal of Experimental Biology. - : The Company of Biologists. - 0022-0949 .- 1477-9145. ; 214:6, s. 907-914
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Tidskriftsartikel (refereegranskat)abstract
- Corticotropin-releasing factor (CRF) is central in the stress response but also modulates several behaviors including anxiety-related behaviors and aggression. In this study, juvenile rainbow trout (Oncorhynchus mykiss) were tested for competitive ability, determined during dyadic fights for dominance, after intracerebroventricular (i.c.v.) administration of CRF, urotensin I (UI), the non-specific CRF antagonist alpha-helical RF9-41 (ahCRF) or the CRF receptor subtype 1-specific antagonist antalarmin, when paired with a mass-matched con-specific injected with saline. In addition, isolated fish received the same substances. Plasma cortisol and brain monoamines were monitored in all fish. Most fish receiving CRF showed a conspicuous behavior consisting of flaring the opercula, opening the mouth and violent shaking of the head from side to side. When this occurred, the fish immediately forfeited the fight. Similar behavior was observed in most fish receiving UI but no effect on outcome of dyadic fights was noted. This behavior seems similar to non-ambulatory motor activity seen in rats and could be anxiety related. Furthermore, fish receiving CRF at a dose of 1000. ng became subordinate, whereas all other treatments had no effects on the outcome of dyadic fights. In addition, isolated fish receiving ahCRF had lower brain stem concentrations of 5-hydroxyindoleacetic acid, serotonin, 3,4-dihydroxyphenylacetic acid and dopamine. In conclusion, CRF seems to attenuate competitive ability, and both CRF and UI seem to induce anxiety-like behavior.
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| 2. |
- Beetz, Andrea, et al.
(författare)
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The Effect of a Real Dog, Toy Dog and Friendly Person on Insecurely Attached Children During a Stressful Task : An Exploratory Study
- 2011
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Ingår i: Anthrozoos. - : Taylor & Francis. - 0892-7936 .- 1753-0377. ; 24:4, s. 349-368
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Tidskriftsartikel (refereegranskat)abstract
- The regulation of stress by an attachment figure is a key feature of attachment relationships. Previous research suggests that in some cases animal companionship may be regarded as an attachment relationship. This may be particularly important for persons with an insecure or disorganized attachment pattern who may find it more difficult than securely attached individuals to accept social support from humans. In our study, we investigated whether 31 boys (aged 7-12 years) with insecure/disorganized attachment would profit more from the presence of a dog (n = 11) than of a friendly human (n = 11) or a toy dog (n = 9) as support during a socially stressful situation (Trier Social Stress Test for Children, TSST-C). Stress levels were assessed via salivary cortisol recorded five times before, during, and after the TSST-C. The behavior of the children was coded from video recordings. Self-reported stress levels did not significantly differ between the groups before and after the TSST-C. Salivary cortisol, however, was significantly lower in the real dog condition than in the other two conditions (Kruskal-Wallis H test on area under the curve increase (AUCi): chi(2) = 15.17, df = 2, p = 0.001). Also, the more the children stroked the dog, the less pronounced was their stress reaction (r(s) = -0.818, p = 0.002). Our data suggest an important role of physical contact in the stress reducing effect. We conclude that the children investigated profited more from interacting with a friendly dog than with either a human or a toy dog in a stressful situation. We discuss the relevance of our findings for animal-assisted interventions.
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| 3. |
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| 4. |
- Binder, Pauline, 1965-, et al.
(författare)
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Hi-TENS combined with PCA-morphine as post caesarean pain relief
- 2011
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Ingår i: Midwifery. - : Elsevier. - 0266-6138 .- 1532-3099. ; 27:4, s. 547-552
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: to examine effectiveness and overall opiate consumption between high-sensory transcutaneous electrical nerve stimulation (Hi-TENS) combined with patient-controlled analgesia with morphine and patient-controlled analgesia with morphine alone following elective (e.g. scheduled) caesarean birth. Design: randomised, controlled study. Setting: a county hospital in south-west Sweden. Participants: 42 multiparous women. Measurements and findings: participants were randomly assigned and connected to patient-controlled analgesia with morphine alone or in combination with Hi-TENS apparatus. Levels of morphine consumed were calculated every third hour during the first 24 hours post partum. Pain and sedation were assessed by visual analogue scale at one, three, six, nine, 12 and 24 hours post partum. Total consumption of morphine differed significantly between the groups: morphine with TENS was 16.2+/-12.6 mg and morphine alone was 33.1+/-20.9 mg (p = 0.007). Assessment of pain relief showed no significant difference. Sedation differed significantly between the groups (p = 0.045), especially between three and 12 hours post partum (p = 0.011). Key conclusions and implications for practice: pain relief from a combination of Hi-TENS and patient-controlled analgesia with morphine was as effective as patient-controlled analgesia with morphine alone, produced less sedation and reduced morphine use by approximately 50%. Women undergoing a caesarean section should be given the opportunity to make an informed choice about post operative pain relief before surgery. A presumed benefit of this treatment combination is that the mother is more alert and better able to interact with her newborn during the first hours after birth without drowsiness due to large doses of opiates.
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| 5. |
- Borg, Julia, et al.
(författare)
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Gastroparesis is associated with oxytocin deficiency, oesophageal dysmotility with hyperCCKemia, and autonomic neuropathy with hypergastrinemia
- 2009
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Ingår i: BMC Gastroenterology. - : BioMed Central. - 1471-230X .- 1471-230X. ; 9, s. Article number 17-
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Tidskriftsartikel (refereegranskat)abstract
- Background: Gastrointestinal (GI) dysmotility and autonomic neuropathy are common problems among diabetics with largely unknown aetiology. Many peptides are involved in the autonomic nervous system regulating the GI tract. The aim of this study was to examine if concentrations of oxytocin, cholecystokinin (CCK), gastrin and vasopressin in plasma differ between diabetics with normal function and dysfunction in GI motility.Methods: Nineteen patients with symptoms from the GI tract who had been examined with gastric emptying scintigraphy, oesophageal manometry, and deep-breathing test were included. They further received a fat-rich meal, after which blood samples were collected and plasma frozen until analysed for hormonal concentrations.Results: There was an increase in postprandial oxytocin plasma concentration in the group with normal gastric emptying (p = 0.015) whereas subjects with delayed gastric emptying had no increased oxytocin secretion (p = 0.114). Both CCK and gastrin levels increased after the meal, with no differences between subjects with normal respective delayed gastric emptying. The concentration of vasopressin did not increase after the meal. In patients with oesophageal dysmotility the basal level of CCK tended to be higher (p = 0.051) and those with autonomic neuropathy had a higher area under the curve (AUC) of gastrin compared to normal subjects (p = 0.007).Conclusion: Reduced postprandial secretion of oxytocin was found in patients with delayed gastric emptying, CCK secretion was increased in patients with oesophageal dysmotility, and gastrin secretion was increased in patients with autonomic neuropathy. The findings suggest that disturbed peptide secretion may be part of the pathophysiology of digestive complications in diabetics.
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| 6. |
- Curtsdotter, Alva, et al.
(författare)
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Ecosystem function in predator-prey food webs : confronting dynamic models with empirical data
- 2019
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Ingår i: Journal of Animal Ecology. - : John Wiley & Sons. - 0021-8790 .- 1365-2656. ; 88:2, s. 196-210
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Tidskriftsartikel (refereegranskat)abstract
- Most ecosystem functions and related services involve species interactions across trophic levels, for example, pollination and biological pest control. Despite this, our understanding of ecosystem function in multitrophic communities is poor, and research has been limited to either manipulation in small communities or statistical descriptions in larger ones. Recent advances in food web ecology may allow us to overcome the trade-off between mechanistic insight and ecological realism. Molecular tools now simplify the detection of feeding interactions, and trait-based approaches allow the application of dynamic food web models to real ecosystems. We performed the first test of an allometric food web model's ability to replicate temporally nonaggregated abundance data from the field and to provide mechanistic insight into the function of predation. We aimed to reproduce and explore the drivers of the population dynamics of the aphid herbivore Rhopalosiphum padi observed in ten Swedish barley fields. We used a dynamic food web model, taking observed interactions and abundances of predators and alternative prey as input data, allowing us to examine the role of predation in aphid population control. The inverse problem methods were used for simultaneous model fit optimization and model parameterization. The model captured >70% of the variation in aphid abundance in five of ten fields, supporting the model-embodied hypothesis that body size can be an important determinant of predation in the arthropod community. We further demonstrate how in-depth model analysis can disentangle the likely drivers of function, such as the community's abundance and trait composition. Analysing the variability in model performance revealed knowledge gaps, such as the source of episodic aphid mortality, and general method development needs that, if addressed, would further increase model success and enable stronger inference about ecosystem function. The results demonstrate that confronting dynamic food web models with abundance data from the field is a viable approach to evaluate ecological theory and to aid our understanding of function in real ecosystems. However, to realize the full potential of food web models, in ecosystem function research and beyond, trait-based parameterization must be refined and extended to include more traits than body size. © 2018 The Authors. Journal of Animal Ecology © 2018 British Ecological Society
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| 7. |
- Eero, Margit, et al.
(författare)
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Food for Thought Eastern Baltic cod in distress : biological changes and challenges for stock assessment
- 2015
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Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 72:8, s. 2180-2186
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Tidskriftsartikel (refereegranskat)abstract
- The eastern Baltic (EB) cod (Gadus morhua) stock was depleted and overexploited for decades until the mid-2000s, when fishing mortality rapidly declined and biomass started to increase, as shown by stock assessments. These positive developments were partly assigned to effective management measures, and the EB cod was considered one of the most successful stock recoveries in recent times. In contrast to this optimistic view, the analytical stock assessment failed in 2014, leaving the present stock status unclear. Deteriorated quality of some basic input data for stock assessment in combination with changes in environmental and ecological conditions has led to an unusual situation for cod in the Baltic Sea, which poses new challenges for stock assessment and management advice. A number of adverse developments such as low nutritional condition and disappearance of larger individuals indicate that the stock is in distress. In this study, we (i) summarize the knowledge of recent changes in cod biology and ecosystem conditions, (ii) describe the subsequent challenges for stock assessment, and (iii) highlight the key questions where answers are urgently needed to understand the present stock status and provide scientifically solid support for cod management in the Baltic Sea.
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| 8. |
- Eklund, Malin B., et al.
(författare)
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Differential effects of repeated long and brief maternal separation on behaviour and neuroendocrine parameters in Wistar dams
- 2009
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Ingår i: Behavioural Brain Research. - : Elsevier. - 0166-4328 .- 1872-7549. ; 203:1, s. 69-75
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Tidskriftsartikel (refereegranskat)abstract
- Repeated, prolonged maternal separation has been suggested to model the development of a depression-like syndrome in rats. The long separations from the pups have been proposed to be stressful for the dams, which in turn could mediate the changes seen in adult offspring. In the present study we investigated whether prolonged maternal separation really is stressful for rat dams by studying parameters known to be affected by long-term stress such as spontaneous motor activity, anxiety-like behaviour, adrenal gland weight and plasma corticosterone levels. Dams were separated from their litter for either 4 h (MS240) or 15 min (MS15) on eight random days during postnatal day 1–14, or left undisturbed (animal facility reared, AFR). After weaning MS240 dams showed decreased peripheral activity and habituated slower in horizontal activity. On the contrary, MS15 dams showed more peripheral activity and less rearing activity compared to both AFR and MS240 dams when habituated to the testing apparatus, suggesting that MS15 dams are more anxious. The adrenal glands from MS15 dams weighed significantly less and plasma corticosterone levels were significantly higher compared to AFR and MS240 dams. These results suggest that repeated brief maternal separations from pups could be stressful for rat mothers, whereas prolonged separations are not. Since these results are in contrast to the current notion that the short separation procedure may be considered as a safe milieu, whereas the prolonged separations have been suggested to be stressful for both dams and pups, further studies in this field are warranted.
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| 9. |
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| 10. |
- Fröberg, Lars, et al.
(författare)
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Age and epiphytic lichen diversity of the dwarf shrub Helianthemum oelandicum on the island of Öland , Sweden
- 2009
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Ingår i: The Lichenologist. - : British Lichen Society. - 0024-2829 .- 1096-1135. ; 41:5, s. 537-545
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Tidskriftsartikel (refereegranskat)abstract
- Lichen cover and diversity was analysed on the dwarf shrub Helianthemum oelandicum (L.) Dum.Cours.at one site in the calcareous grassland of the area known as the 'Great Alvar' on the Island of Öland, Sweden. The age of 22 phorophytes was determined by ring counting and varied from 8 to 41 years and was accurately predicted by the root diameter. A total of 18 lichen species were found, with a range between 0 and 13 species per phorophyte. The number of lichen species on living H. oelandicum was correlated with the phorophyte age. The number of lichen species and their coverage was greater on dead compared with living phorophytes. The species number was also higher on thin branches compared with thick branches and roots and some of the species showed preferences for dead phorophytes, and for thin branches. This study of lichen colonization and growth on dwarf shrubs in relation to phorophyte age is a new application of herbchronology.
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