| 1. |
- Ahlberg, Erik, et al.
(författare)
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"Vi klimatforskare stödjer Greta och skolungdomarna"
- 2019
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Ingår i: Dagens nyheter (DN debatt). - 1101-2447.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- DN DEBATT 15/3. Sedan industrialiseringens början har vi använt omkring fyra femtedelar av den mängd fossilt kol som får förbrännas för att vi ska klara Parisavtalet. Vi har bara en femtedel kvar och det är bråttom att kraftigt reducera utsläppen. Det har Greta Thunberg och de strejkande ungdomarna förstått. Därför stödjer vi deras krav, skriver 270 klimatforskare.
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| 2. |
- Arehag, Marie, 1952, et al.
(författare)
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Outcomes-focused evaluation of engineering programs - Inhibitor or stimulant for improvement?
- 2013
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Ingår i: Proceedings of the 9th International CDIO Conference, Cambridge, USA.
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Konferensbidrag (refereegranskat)abstract
- In Sweden, a new model for quality evaluation of higher education is being introduced. It is internationally unique. A very strong emphasis on assessing the quality of an entire education through its outcomes, defined by samples of final degree reports, is perhaps the most original feature of the model. This is claimed to enable a direct assessment of quality rather than the indirect assessment used in conventional models. The model has, however, been intensively debated during its development and first years of use. The aims of this paper are first to evaluate in what ways and to what extent the Swedish national model for evaluation of higher education contributes to the quality improvement of the evaluated programs, and second to describe and evaluate an approach for organizing the project to prepare the evaluation documentation for a large-scale education evaluation. The paper concludes that on an overall and averaged level, the project participants estimated that the model will contribute to positive effects. Specific areas are identified including ethics and focus of final degree reports. However, there is a strong variance in the data: There is a substantial fraction of participants who have not identified any improvements or weak spots, and who do not think that the evaluation preparation will positively affect education quality development. Chalmers University of Technology chose to approach the evaluation with a centrally managed project. The setup gave possibilities for rationalization through common training, supporting materials, a common document database and for information sharing across departmental boundaries. Nevertheless, the project was very time-consuming with an average of 540 hours spent for each program/degree.
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| 3. |
- Edström-Hägerwall, Anneli, et al.
(författare)
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Alpha-1-microglobulin protects from heme induced placenta and kidney damage in a pregnant ewe model for preeclampsia
- 2013
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Ingår i: Pregnancy Hypertension. - : Elsevier BV. - 2210-7789. ; 3:2, s. 1-70
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Konferensbidrag (refereegranskat)abstract
- INTRODUCTION: Previous gene expression analysis have identified fetal hemoglobin (HbF) as a plausible etiological factor in preeclampsia. Free hemoglobin and its degradation products, e.g. heme, are known to cause oxidative stress, tissue damage, and vaso-constriction, typical findings in preeclampsia.OBJECTIVE: To study alpha-1-microglobulin (A1M), an endogenous radical scavenger and heme-binder, as a potential treatment for preeclampsia using the pregnant ewe preeclampsia model. Free Hb and heme are known to take part in the pathology of this model and therefor well suited for evaluation of recombinant A1M as a therapy.METHODS: 11 pregnant ewes, at gestational age 125-131 days, were acclimatized for 36h and then starved for another 36h to induce preeclampsia symptoms. At the end of starvation period, they were treated either with placebo (n=6) or A1M injections (n=5). After injections, food was re-introduced and ewes further followed for 72h. The ewes were sacrificed the 6th day after beginning of acclimatization. Throughout the 6 days, the animals were monitored for blood pressure and different blood and urine parameters. Whole blood, kidney and placenta tissue samples were collected from the ewes. Gene expression analysis, blood analysis, histology and electron microscopy were used to evaluate the therapeutic effects of A1M.RESULTS: Starvation increased the amount of free heme in the blood. The ultrastructure of the placenta and kidney were damaged in a way similar to what previously have been described for PE. The glomeruli and the tubuli were damaged which was reflected by increased Ficol clearance and increased plasma creatinine levels. Treatment with A1M significantly normalized the kidney functions. The most profound changes on gene expression level were found in white blood cells in the starved animals. Starvation decreases mRNA expression for anti-oxidants such as CAT (P=0.04), SOD1 (P=0.008), SOD2 (1.8-fold) as well as angiogenetic factors such as VEGF (P=0.02) and HGF (1.6-fold). A1M treatment rescued the decreased expression of SOD2 (P=0.04) and HGF (2-fold).CONCLUSION: A1M is well tolerated and shows high potential as a treatment for PE-like symptoms in the pregnant ewe model for PE.
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| 4. |
- Engelhardt, Josefin, et al.
(författare)
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Severe thiamine deficiency in eastern Baltic cod (Gadus morhua)
- 2020
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 15:1
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Tidskriftsartikel (refereegranskat)abstract
- The eastern Baltic cod (Gadus morhua) population has been decreasing in the Baltic Sea for at least 30 years. Condition indices of the Baltic cod have decreased, and previous studies have suggested that this might be due to overfishing, predation, lower dissolved oxygen or changes in salinity. However, numerous studies from the Baltic Sea have demonstrated an ongoing thiamine deficiency in several animal classes, both invertebrates and vertebrates. The thiamine status of the eastern Baltic cod was investigated to determine if thiamine deficiency might be a factor in ongoing population declines. Thiamine concentrations were determined by chemical analyses of thiamine, thiamine monophosphate and thiamine diphosphate (combined SumT) in the liver using high performance liquid chromatography. Biochemical analyses measured the activity of the thiamine diphosphate-dependent enzyme transketolase to determine the proportion of apoenzymes in both liver and brain tissue. These biochemical analyses showed that 77% of the cod were thiamine deficient in the liver, of which 13% had a severe thiamine deficiency (i.e. 25% transketolase enzymes lacked thiamine diphosphate). The brain tissue of 77% of the cod showed thiamine deficiency, of which 64% showed severe thiamine deficiency. The thiamine deficiency biomarkers were investigated to find correlations to different biological parameters, such as length, weight, otolith weight, age (annuli counting) and different organ weights. The results suggested that thiamine deficiency increased with age. The SumT concentration ranged between 2.4-24 nmol/g in the liver, where the specimens with heavier otoliths had lower values of SumT (P = 0.0031). Of the cod sampled, only 2% of the specimens had a Fulton's condition factor indicating a healthy specimen, and 49% had a condition factor below 0.8, indicating poor health status. These results, showing a severe thiamine deficiency in eastern Baltic cod from the only known area where spawning presently occurs for this species, are of grave concern.
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| 5. |
- Feng, Shaohong, et al.
(författare)
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Dense sampling of bird diversity increases power of comparative genomics
- 2020
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 587:7833
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Tidskriftsartikel (refereegranskat)abstract
- Whole-genome sequencing projects are increasingly populating the tree of life and characterizing biodiversity(1-4). Sparse taxon sampling has previously been proposed to confound phylogenetic inference(5), and captures only a fraction of the genomic diversity. Here we report a substantial step towards the dense representation of avian phylogenetic and molecular diversity, by analysing 363 genomes from 92.4% of bird families-including 267 newly sequenced genomes produced for phase II of the Bird 10,000 Genomes (B10K) Project. We use this comparative genome dataset in combination with a pipeline that leverages a reference-free whole-genome alignment to identify orthologous regions in greater numbers than has previously been possible and to recognize genomic novelties in particular bird lineages. The densely sampled alignment provides a single-base-pair map of selection, has more than doubled the fraction of bases that are confidently predicted to be under conservation and reveals extensive patterns of weak selection in predominantly non-coding DNA. Our results demonstrate that increasing the diversity of genomes used in comparative studies can reveal more shared and lineage-specific variation, and improve the investigation of genomic characteristics. We anticipate that this genomic resource will offer new perspectives on evolutionary processes in cross-species comparative analyses and assist in efforts to conserve species. A dataset of the genomes of 363 species from the Bird 10,000 Genomes Project shows increased power to detect shared and lineage-specific variation, demonstrating the importance of phylogenetically diverse taxon sampling in whole-genome sequencing.
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| 6. |
- Hagström, Josefin, et al.
(författare)
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Use of and Experiences With Online Access to Electronic Health Records for Parents, Children, and Adolescents : Protocol for a Scoping Review
- 2022
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Ingår i: JMIR Research Protocols. - : JMIR Publications Inc.. - 1929-0748. ; 11:6
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Forskningsöversikt (refereegranskat)abstract
- Background: As patient online access to electronic health records becomes the standard, implementation of access for adolescents and parents varies across providers, regions, and countries. There is currently no international compilation of evidence to guide policy decisions in matters such as age limit for access and the extent of parent proxy access.Objective: This paper presents the protocol for a scoping review of different stakeholders’ (including but not limited to end users) perspectives on use, opinions, and experiences pertaining to online access to electronic health records by parents, children, and adolescents.Methods: This scoping review will be conducted according to the Arksey and O’Malley framework. Several databases will be used to conduct a literature search (PubMed, CINAHL, and PsycInfo), in addition to literature found outside of these databases. All authors will participate in screening identified papers, following the research question: How do different stakeholders experience parents’, children’s, and adolescents’ online access to the electronic health records of children and adolescents? Data abstraction will include but will not be limited to publication type, publication year, country, sample characteristics, setting, study aim, research question, and conclusions. The data to be analyzed are from publicly available secondary sources, so this study does not require an ethics review.Results: The results from this scoping review will be presented in a narrative form, and additional data on study characteristics will be presented in diagrams or tabular format. This scoping review protocol was first initiated by Uppsala University in June 2021 as part of the NordForsk-funded research project NORDeHEALTH. The results are expected to be presented in a scoping review in June 2022. The results will be disseminated through stakeholder meetings, scientific conference presentations, oral presentations to the public, and publication in a peer-reviewed journal.Conclusions: This is, to our knowledge, the first study to map the literature on the use and experiences of parents’ and adolescents’ online access to the electronic health records of children and adolescents. The findings will describe what benefits and risks have been experienced by different stakeholders so far in different countries. A mapping of studies could inform the design and implementation of future regulations around access to patient-accessible electronic health records.
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| 7. |
- Hagström, Josefin, et al.
(författare)
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Views, Use, and Experiences of Web-Based Access to Pediatric Electronic Health Records for Children, Adolescents, and Parents : Scoping Review
- 2022
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Ingår i: Journal of Medical Internet Research. - : JMIR Publications Inc.. - 1438-8871. ; 24:11
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Forskningsöversikt (refereegranskat)abstract
- Background: Ongoing efforts worldwide to provide patients with patient-accessible electronic health records (PAEHRs) have led to variability in adolescent and parental access across providers, regions, and countries. There is no compilation of evidence to guide policy decisions in matters such as access age and the extent of parent proxy access. In this paper, we outline our scoping review of different stakeholders’ (including but not limited to end users) views, use, and experiences pertaining to web-based access to electronic health records (EHRs) by children, adolescents, and parents. Objective: The aim of this study was to identify, categorize, and summarize knowledge about different stakeholders’ (eg, children and adolescents, parents, health care professionals [HCPs], policy makers, and designers of patient portals or PAEHRs) views, use, and experiences of EHR access for children, adolescents, and parents. Methods: A scoping review was conducted according to the Arksey and O’Malley framework. A literature search identified eligible papers that focused on EHR access for children, adolescents, and parents that were published between 2007 and 2021. A number of databases were used to search for literature (PubMed, CINAHL, and PsycINFO). Results: The approach resulted in 4817 identified articles and 74 (1.54%) included articles. The papers were predominantly viewpoints based in the United States, and the number of studies on parents was larger than that on adolescents and HCPs combined. First, adolescents and parents without access anticipated low literacy and confidentiality issues; however, adolescents and parents who had accessed their records did not report such concerns. Second, the main issue for HCPs was maintaining adolescent confidentiality. This remained an issue after using PAEHRs for parents, HCPs, and other stakeholders but was not an experienced issue for adolescents. Third, the viewpoints of other stakeholders provided a number of suggestions to mitigate issues. Finally, education is needed for adolescents, parents, and HCPs. Conclusions: There is limited research on pediatric PAEHRs, particularly outside the United States, and on adolescents’ experiences with web-based access to their records. These findings could inform the design and implementation of future regulations regarding access to PAEHRs. Further examination is warranted on the experiences of adolescents, parents, and HCPs to improve usability and utility, inform universal principles reducing the current arbitrariness in the child’s age for own and parental access to EHRs among providers worldwide, and ensure that portals are equipped to safely and appropriately manage a wide variety of patient circumstances. International Registered Report Identifier (IRRID): RR2-10.2196/36158
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| 8. |
- Hansson, Josefin, et al.
(författare)
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The risk of graft loss 5 years after kidney transplantation is increased if cold ischemia time exceeds 14 hours
- 2018
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Ingår i: Clinical Transplantation. - : Wiley. - 0902-0063. ; 32:9
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Tidskriftsartikel (refereegranskat)abstract
- Background: The state of the evidence is unclear regarding the impact of cold ischemia time (CIT) on the outcome of kidney transplantation. The aim of this study was to investigate the effect of CIT on the short- and long-term function of kidneys transplanted at the Sahlgrenska University Hospital in 2007-2009 from donors after brain death (DBDs). Methods: This study was designed as a retrospective analysis of data from local and national transplantation registers. The study endpoints were as follows: delayed graft function (DGF), primary nonfunction (PNF), biopsy-proven acute rejection (BPAR), serum creatinine (S-creatinine) level at discharge, days of hospitalization after transplantation, and graft survival at 5 years post-transplantation. Adjusted regression analyses were used to determine causal relationships with CIT. A further aim was to estimate a threshold for CIT by analyzing event rates and coordinates of the receiver-operated characteristic (ROC) curve. Results: There was a causal relationship between CIT as a continuous variable and the following endpoints: graft survival at 5 years post-transplantation, though this was not significant (hazard ratio (HR) 1.07, P = 0.057), DGF (odds ratio (OR) 1.09, P = 0.03) and S-creatinine (P = 0.003). In our material, the risk for impaired outcome was higher with longer CIT. We were therefore able to estimate a threshold value for CIT, set to 14 hours for both graft survival at 5 years post-transplantation and DGF. This was proved with significance by analyzing both event rates and the coordinates of the ROC curve. The risk of graft loss increased, with HR 2.3 (P = 0.023), when comparing a CIT cutoff of >= 14 hours with CIT < 14 hours. Delayed graft function increased, with an OR of 2.6 (P = 0.001). Conclusion: Our study confirms that, in this patient material, longer CIT was associated with increased risk for both impaired graft survival and incidence of DGF. We estimated a threshold for CIT of 14 hours.
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| 9. |
- Hellgren, Josefin, et al.
(författare)
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Occurrence of Salmonella, Campylobacter, Clostridium and Enterobacteriaceae in raw meat-based diets for dogs
- 2019
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Ingår i: Veterinary Record. - : Wiley. - 0042-4900 .- 2042-7670. ; 184
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Tidskriftsartikel (refereegranskat)abstract
- The practice of feeding raw meat-based diets (RMBD) to dogs has increased in popularity in recent years. However, RMBD are based on offal that has not undergone any type of treatment to reduce the microbial content, so there is a risk of potential pathogenic microorganisms being present. Frozen samples from 60 RMBD packs produced by 10 different manufacturers were analysed for their content of bacteria belonging to the family Enterobacteriaceae, for Clostridium perfringens and for the presence of Salmonella and Campylobacter. Enterobacteriaceae were detected in all 60 samples and in 31 samples exceeded a level of 5000 bacteria/g, which is the threshold for satisfactory microbial hygiene according to EU regulations. In two samples, the amount of C. perfringens exceeded 5000 bacteria/g, which is the maximum level of anaerobic bacteria permitted by Swedish national guidelines. Salmonella species were found in four (7 per cent) and Campylobacter species in three (5 per cent) samples. These results show that it is critical to maintain good hygiene when storing, handling and feeding RMBD, in order to limit the potential health risks to animals and humans, especially young and immunocompromised individuals.
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| 10. |
- Hosia, A, et al.
(författare)
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Interactions between native and alien ctenophores: Beroe gracilis and Mnemiopsis leidyi in Gullmarsfjorden
- 2011
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Ingår i: MARINE ECOLOGY-PROGRESS SERIES. - 0171-8630. ; 422, s. 129-138
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Tidskriftsartikel (refereegranskat)abstract
- We experimentally quantified predation rates between the native North Sea ctenophore Beroe gracilis and the introduced Mnemiopsis leidyi. A series of incubation experiments with varying M. leidyi prey concentrations (0.15 to 2.37 ind. l–1) and sizes (mean oral-aboral length: 5.9 to 20.6 mm) was conducted, and digestion rates were measured. B. gracilis fed readily on M. leidyi and reproduced on this diet. However, B. gracilis were unable to entirely ingest M. leidyi approaching their own size, resulting in a size refuge from predation. Larger prey were often partially consumed, and the proportion of prey that was only partially eaten increased with prey size. Observed maximum clearance rates for whole prey were from 0.42 to 0.97 l ind.–1 h–1. Ingestion rates of whole prey increased linearly with prey concentration for the smaller prey, but leveled off at the higher prey concentrations for the larger sizes, indicating handling limitation. The handling limitations probably largely stemmed from digestion time (1.6 to 8.4 h for 4 to 12 mm prey) and gut volume. Applying the determined clearance rates to concurrent in situ abundances of M. leidyi and B. gracilis suggested a slight predation impact on the M. leidyi population (overall mortality: 8.8 × 10–4 d–1). The predatory interactions between the 2 species are further complicated by transitional and lobate stage M. leidyi being able to feed on young B. gracilis.
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| 11. |
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| 12. |
- Moberg, Christina, et al.
(författare)
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De unga gör helt rätt när de stämmer staten
- 2022
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Ingår i: Aftonbladet. - 1103-9000.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- 1 620 forskare och lärare i forskarvärlden: Vi ställer oss bakom Auroras klimatkrav
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| 13. |
- Nääv, Åsa, et al.
(författare)
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A1M Ameliorates Preeclampsia-Like Symptoms in Placenta and Kidney Induced by Cell-Free Fetal Hemoglobin in Rabbit.
- 2015
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 10:5
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Tidskriftsartikel (refereegranskat)abstract
- Preeclampsia is one of the most serious pregnancy-related diseases and clinically manifests as hypertension and proteinuria after 20 gestational weeks. The worldwide prevalence is 3-8% of pregnancies, making it the most common cause of maternal and fetal morbidity and mortality. Preeclampsia lacks an effective therapy, and the only "cure" is delivery. We have previously shown that increased synthesis and accumulation of cell-free fetal hemoglobin (HbF) in the placenta is important in the pathophysiology of preeclampsia. Extracellular hemoglobin (Hb) and its metabolites induce oxidative stress, which may lead to acute renal failure and vascular dysfunction seen in preeclampsia. The human endogenous protein, α1-microglobulin (A1M), removes cell-free heme-groups and induces natural tissue repair mechanisms. Exogenously administered A1M has been shown to alleviate the effects of Hb-induced oxidative stress in rat kidneys. Here we attempted to establish an animal model mimicking the human symptoms at stage two of preeclampsia by administering species-specific cell-free HbF starting mid-gestation until term, and evaluated the therapeutic effect of A1M on the induced symptoms. Female pregnant rabbits received HbF infusions i.v. with or without A1M every second day from gestational day 20. The HbF-infused animals developed proteinuria and a significantly increased glomerular sieving coefficient in kidney that was ameliorated by co-administration of A1M. Transmission electron microscopy analysis of kidney and placenta showed both intracellular and extracellular tissue damages after HbF-treatment, while A1M co-administration resulted in a significant reduction of the structural and cellular changes. Neither of the HbF-treated animals displayed any changes in blood pressure during pregnancy. In conclusion, infusion of cell-free HbF in the pregnant rabbits induced tissue damage and organ failure similar to those seen in preeclampsia, and was restored by co-administration of A1M. This study provides preclinical evidence supporting further examination of A1M as a potential new therapy for preeclampsia.
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| 14. |
- Strandh, Maria, et al.
(författare)
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Natural selection acts on floral traits associated with selfing rate among populations of Mixed-Mating collinsia heterophylla (Plantaginaceae)
- 2017
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Ingår i: International Journal of Plant Sciences. - : University of Chicago Press. - 1058-5893 .- 1537-5315. ; 178:8, s. 594-606
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Tidskriftsartikel (refereegranskat)abstract
- Premise of research. A major aim in plant research is to understand the micro-and macroevolutionary processes generating the great diversity of mating systems and floral traits found in flowering plants. Using Collinsia heterophylla, a mixed-mating species in a genus with described variation in selfing rate and associated floral traits among species, we investigated (i) intraspecific selfing rate variation in relation to variation in environmental factors and floral traits and (ii) whether selection or genetic drift determine floral trait variation. Methodology. We estimated selfing rate in 21 Californian populations by means of microsatellite markers and investigated its relationship with sampling region, altitude, population ground cover, stage of stigma receptivity, stage of anther-stigma contact (indicating stage of self-pollination), flower size, and start of flowering. Phenotypic floral trait differentiation (PST) for the floral traits was contrasted with neutral genetic differentiation (FST). Pivotal results. The population selfing rate ranged between 0.16 and 0.71 and differed between regions, but it did not correlate with environmental factors. The best predictor of high selfing rate was early stigma receptivity. Stage of anther-stigma contact showed a nonlinear quadratic relation with selfing rate. PST was substantially higher than FST in the four traits, suggesting that variation in mating-related floral traits is shaped by natural selection. Conclusions. The importance of stage of stigma receptivity for predicting selfing rate in C. heterophylla is in line with the pattern found among Collinsia species, potentially indicating that microevolutionary processes in mixed mating influence macroevolutionary processes. The detected effect of natural selection acting on stage of stigma receptivity, in combination with previously detected genetic influence on this trait, gives support to the hypothesis that variability in mating system is adaptive.
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| 15. |
- Sverrisson, Kristinn, et al.
(författare)
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Extracellular fetal hemoglobin induces increases in glomerular permeability: inhibition with alfa-1-microglobulin and tempol
- 2014
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Ingår i: American Journal of Physiology-Renal Physiology. - : American Physiological Society. - 1522-1466 .- 1931-857X. ; 306:4, s. 442-448
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Tidskriftsartikel (refereegranskat)abstract
- Extracellular fetal hemoglobin (HbF) and adult hemoglobin (HbA) are proinflammatory and generate ROS. Increased plasma levels of extracellular HbF have recently been reported to occur in early preeclampsia. α1-Microglobulin (A1M) is a physiological heme-binding protein and radical scavenger that has been shown to counteract vascular permeability increases induced by HbA in the perfused placenta. The present study was performed to investigate whether HbF and HbA will increase glomerular permeability in vivo and to test whether A1M and tempol, a ROS scavenger, can prevent their effects. Anesthetized Wistar rats were continuously infused intravenously with either HbA, HbF, or cyano-inactivated HbF together with FITC-Ficoll-70/400, inulin, and51Cr-labeled EDTA for 2 h. Plasma samples and urine samples (left ureter) were taken repeatedly and analyzed by high-performance size exclusion chromatography to assess glomerular sieving coefficients for Ficoll of radius 10–80 Å. In separate experiments, A1M or tempol was given before and during Hb infusions. Extracellular HbF caused rapid, transient increases in glomerular permeability to large Ficoll molecules (50–80Å), contrary to the effects of HbA and cyano-inactivated HbF. For HbF, glomerular sieving coefficients for Ficoll of radius 60Å increased from 3.85 ± 0.85 × 10−5to 2.60 ± 0.96 × 10−4at 15 min, changes that were abrogated by tempol and reduced by A1M. In conclusion, our data demonstrate that extracellular HbF, infused systemically, can acutely increase glomerular permeability through inducing oxidative stress.
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| 16. |
- Titelman, Josefin, 1973, et al.
(författare)
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Feeding rates of the jellyfish Aurelia aurita on fish larvae
- 2006
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Ingår i: Marine Biology. - 0025-3162. ; 149:2, s. 297-306
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Tidskriftsartikel (refereegranskat)abstract
- We quantified feeding rates of field caught Aurelia aurita feeding on yolk sac cod (Gadus morhua) larvae in a series of incubation experiments. A short-time (similar to 1 h) functional response experiment with a wide range of prey concentrations (0.5-16 prey l(-1)supercript stop, initial concentration) revealed that ingestion rates increased linearly over this range, such that clearance rates were similar between the different prey concentrations. This suggests that A. aurita is capable of efficiently utilizing dense prey patches. This indication was further supported by a linear increase of prey captured by A. aurita during 2.5 h of feeding at extremely high prey concentration (> 200 prey l(-1)). Clearance rate in darkness scaled with jellyfish diameter to a power of similar to 1.7 for jellyfish 3.9-9.5 cm in diameter. The jellyfish did not alter their umbrella pulse frequency in response to presence of fish larvae. There were no significant differences between A. aurita feeding rates in light and darkness for yolk sac prey ages 0-7 days (at 7.5 degrees C). Although prey vision and escape abilities of fish may develop rapidly during early larval ontogeny, these factors apparently have little impact on interactions with predators such as A. aurita during the yolk sac stage.
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| 17. |
- Titelman, Josefin, 1973, et al.
(författare)
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Predator-induced vertical behavior of a ctenophore
- 2012
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Ingår i: Hydrobiologia. - : Springer Science and Business Media LLC. - 0018-8158 .- 1573-5117. ; 690:1, s. 181-187
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Tidskriftsartikel (refereegranskat)abstract
- Although many studies have focused on Mnemiopsis leidyi predation, little is known about the role of this ctenophore as prey when abundant in native and invaded pelagic systems. We examined the response of the ctenophore M. leidyi to the predatory ctenophore Beroe ovata in an experiment in which the two species could potentially sense each other while being physically separated. On average, M. leidyi responded to the predator's presence by increasing variability in swimming speeds and by lowering their vertical distribution. Such behavior may help explain field records of vertical migration, as well as stratified and near-bottom distributions of M. leidyi.
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| 18. |
- Wester Rosenlöf, Lena, et al.
(författare)
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A1M/α1-Microglobulin Protects from Heme-Induced Placental and Renal Damage in a Pregnant Sheep Model of Preeclampsia.
- 2014
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Preeclampsia (PE) is a serious pregnancy complication that manifests as hypertension and proteinuria after the 20(th) gestation week. Previously, fetal hemoglobin (HbF) has been identified as a plausible causative factor. Cell-free Hb and its degradation products are known to cause oxidative stress and tissue damage, typical of the PE placenta. A1M (α1-microglobulin) is an endogenous scavenger of radicals and heme. Here, the usefulness of A1M as a treatment for PE is investigated in the pregnant ewe PE model, in which starvation induces PE symptoms via hemolysis. Eleven ewes, in late pregnancy, were starved for 36 hours and then treated with A1M (n = 5) or placebo (n = 6) injections. After injections, the ewes were re-fed and observed for additional 72 hours. They were monitored for blood pressure, proteinuria, blood cell distribution and clinical and inflammation markers in plasma. Before termination, the utero-placental circulation was analyzed with Doppler velocimetry and the kidney glomerular function was analyzed by Ficoll sieving. At termination, blood, kidney and placenta samples were collected and analyzed for changes in gene expression and tissue structure. The starvation resulted in increased amounts of the hemolysis marker bilirubin in the blood, structural damages to the placenta and kidneys and an increased glomerular sieving coefficient indicating a defect filtration barrier. Treatment with A1M ameliorated these changes without signs of side-effects. In conclusion, A1M displayed positive therapeutic effects in the ewe starvation PE model, and was well tolerated. Therefore, we suggest A1M as a plausible treatment for PE in humans.
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