558 results on '"Jensen, Louise A"'
Search Results
552. Uranium and toxic metal uptake by the earthworm Eisenia hortensis in contaminated soils
- Author
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Schöpke, Christian Alexander, Skipperud, Lindis, Wærsted, Frøydis Meen, and Jensen, Louise Kiel
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Mathematics and natural science: 400::Chemistry: 440::Environmental chemistry, natural environmental chemistry: 446 [VDP] ,NORM ,Metals ,Mathematics and natural science: 400::Zoology and botany: 480::Ecotoxicology: 489 [VDP] ,Earthworm ,Eisenia hortensis ,Concentration Ratio - Abstract
Earthworms are present in nearly every terrestrial ecosystem worldwide and play an important role in the transport and availability of nutrients and other elements in soil. Even more ubiquitous than earthworms are naturally occurring radioactive material (NORM) and toxic metals – elements that are present in all soils, albeit in widely varying concentrations. These elements often can be found in a bound state (e.g. within a rock matrix), but can as a result of both natural and anthropogenic processes (e.g. mining and construction, wood burning, weathering) become more readily accessible for uptake in living organisms. The aim of this study was to explore uptake of Mg, K, S, Zn, Cu, Cr, Mn, Co, Mo, V, Ni, As, Cd, Sn, Pb and U in varying degrees of contaminated soil by the earthworm species Eisenia hortensis in a laboratory setting. Furthermore, we wanted to compare uptake observed in the laboratory to uptake in earthworms sampled in the same soil as used in one of the laboratory treatments, chosen for its known high natural uranium (U) concentration. A control soil was collected from an area with low concentrations of NORM and toxic metals (Romeriksåsen), and the soil from the high U region (Orrefjell) was mixed with alum shale from Gran, Hadeland, to give a gradient of toxic metals and a stable high U concentration. It was shown that increasing the metal concentration while maintaining a stable high U concentration had no effect on the assimilation of U by E. hortensis. In addition, increased mortality and decreased reproductive health were observed at the highest concentrations of metals tested, while at lower levels a positive effect on reproductive health was observed. Metal and NORM uptake in laboratory and field-sampled earthworms in the same soil was constant for most elements, with an increased concentration in laboratory earthworms for Co and Pb. Meitemark er å finne i de fleste terrestriske økosystemer og er viktige for transport og tilgjenglighet av næringsstoffer og andre grunnstoffer i jord. Enda mer utbredt enn meitemark er «naturlig forekommende radioaktivt materiale (NORM)» og giftige metaller - grunnstoffer som finnes i alle typer jord, men i vidt forskjellige konsentrasjoner. Disse grunnstoffene er ofte sterkt bundet i mineraler eller andre matriser i jord, men kan bli mer tilgjengelige som resultat av menneskelige og naturlige prosesser (for eksempel gruvedrift, bygg- og annleggsvirksomhet, forbrenning av fossilt materiale, forvitring). Målet av denne studien var å undersøke opptak av Mg, K, S, Zn, Cu, Cr, Mn, Co, Mo, V, Ni, As, Cd, Sn, Pb og U fra jord kontaminert i ulik grad til meitemarkarten Eisenia hortensis i laboratorieforsøk. I tillegg var det ønskelig å sammenligne opptak observert i laboratoriet med opptak i mark prøvetatt i felt i samme jord – jord som ble valgt på grunn av kjent høy urankonsentrasjon. Kontrolljord ble hentet fra et område med lave konsentrajoner av NORM og giftige metaller (Romeriksåsen), og jord med høyt uraninnhold (Orrefjell) ble blandet sammen med alunskifer fra Gran (Hadeland) for å skape en gradient av giftige metaller og en stabil høy urankonsentrasjon. Økende metallkonsentrasjoner i jord med en stabil høy urankonsentrasjon hadde ingen påvirkning på opptak av uran i E. Hortensis. Økt dødlighet og lavere reproduksjon ble observert i jorden med høyest innhold av metaller, mens i jorden med middels innhold av metaller ble det observert en positiv effekt på reproduktivitet. Opptak av metaller og NORM i laboratorie- og feltprøver var tilnærmet likt for de fleste grunnstoffer, med unntak av Co og Pb som ble tatt opp i større grad av mark i laboratorieforsøket. M-RAD
- Published
- 2017
553. Elevated natural radioactivity in undisturbed forest and mountain areas of arctic Norway – local geology, soil characteristics, and transfer to biota.
- Author
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Thørring, Håvard, Wærsted, Frøydis Meen, Raaness, Agnes, Skipperud, Lindis, and Jensen, Louise Kiel
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NATURAL radioactivity , *MOUNTAIN forests , *GEOLOGY , *SOIL mineralogy , *HUMUS , *MOUNTAIN soils , *TUNDRAS - Abstract
This study deals with the geology in areas close to a large unexploited uranium deposit and the impact of bedrock characteristics on levels of radionuclides and other elements in soil and biota. Factors influencing soil inventory and ecosystem transfer are discussed, focussing on 238U, 226Ra, and 210Pb. Field work was carried out in Salangen Valley in Northern Norway. Sampling stations for soil and biota covered different habitats – grassland, birch forest and low alpine heathland. The geological survey confirmed uranium-bearing minerals in granitic gneiss and pegmatites. There was large variation in the local occurrence of uranium, reflecting the irregular nature of the pegmatite. Activity concentrations of 238U, 226Ra, and 210Pb in surface soil were elevated at sites close to U-enhanced bedrock, compared to sites with other types of bedrock. Particularly high soil levels were found for 226Ra and 210Pb, whereas activity concentrations of 238U were more variable, depending of local soil characteristics. Levels of other natural radionuclides (40K, 232Th) merely increased with soil mineral content, and concentrations of heavy metals were generally low at all sites. External dose rate (1 m above ground surface) was closely correlated with 226Ra levels in soil. Plant levels of 238U and 226Ra varied by several orders of magnitude depending on soil level and plant species, whereas plant levels of 210Pb and 210Po were largely affected by aerial fallout. Berries generally contained lower levels of 238U and 226Ra than green plant parts. As was the case for plants, the levels of 238U in earthworms were strongly correlated with the respective concentrations in the soil. Soil-to-plant transfer was markedly higher for 226Ra than for 238U. For both radionuclides, a positive correlation was found between concentration ratios of V. myrtillus (heath) and soil organic matter content. The 238U concentration ratios for earthworms were generally two orders of magnitude higher than for plants. Image 1 • Distribution of naturally occurring radionuclides in undisturbed areas. • Geological characterization supports variation in soil inventory of radionuclides. • Transfer data to biota covering a gradient of soil activity concentrations. • Plant activity concentrations and transfer was highest for radium-226. [ABSTRACT FROM AUTHOR]
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- 2020
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554. Realism and usefulness of multispecies experiment designs with regard to application in radioecology: A review.
- Author
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Haanes, Hallvard, Hansen, Elisabeth Lindbo, Hevrøy, Tanya Helena, Jensen, Louise Kiel, Gjelsvik, Runhild, Jaworska, Alicja, and Bradshaw, Clare
- Abstract
• Only 4/406 studies assess ionizing radiation effects; the knowledge gap is clear. • Even small microcosms can be ecologically complex, stable and long lasting. • Small microcosms are beneficial due to radioactive waste and dosimetry constraints. • Designs vary from standardised to ecologically complex excised parts of nature. • Studies of indirect effects benefit from more replicates and longer experiments. Multispecies experiments like microcosms and mesocosms are widely used in many fields of research but not in radioecology. In radioecology, size limitations are important as large experimental volumes involve problems with waste (radionuclides), or shielding, absorption and available space in gamma fields (often within a climate chamber). We have therefore performed a literature review (ISI Web of Science, n = 406) of the design and properties of multispecies effect studies <100 L in size and with three or more mentioned taxa in other research fields to assess their suitability to radioecology. Studies with more mentioned taxa assess structural ecosystem parameters more often than studies with fewer mentioned taxa, while the opposite trend is seen for indirect effects/interactions. Studies of indirect effects benefit from more replicates and longer experiments. Almost all studies assess some ecosystem level parameter but only a quarter take a holistic approach assessing both structural and functional as well as indirect effects. We find that most cosms are custom-made systems, rather than standardised designs. Unmanipulated cosms consist of excised portions of the natural environment with a higher number of mentioned taxa, high ecological complexity and high realism, but have a relatively low replicability. In contrast, standardised cosms with fewer mentioned taxa have less ecological complexity but much higher replicability. This literature review shows that smaller cosm sizes have similar ecological complexity (e.g. number of taxa and trophic levels) and experimental duration as larger sized cosms, allowing for ecologically-relevant investigations, despite their small size. We encourage multispecies radioecology studies, preferably with environmental relevant doses and sufficient detail on dosimetry. [ABSTRACT FROM AUTHOR]
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- 2020
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555. The host response to bacterial bone infection involves a local upregulation of several acute phase proteins.
- Author
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Lüthje, Freja Lea, Blirup-Plum, Sophie Amalie, Møller, Nadia Sara, Heegaard, Peter M.H., Jensen, Henrik Elvang, Kirketerp-Møller, Klaus, Gottlieb, Hans, Skovgaard, Kerstin, and Jensen, Louise Kruse
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ACUTE phase proteins , *BACTERIAL diseases , *CALCITONIN , *BONES , *C-reactive protein , *PORCINE reproductive & respiratory syndrome , *OSTEOMYELITIS - Abstract
Bone infections often become chronic and can be difficult to diagnose. In the present study, the osseous gene expression of several acute phase proteins (APPs) during osteomyelitis was investigated in a porcine model of implant associated osteomyelitis (IAO) (sampled 5, 10 and 15 days after infection) and in slaughter pigs with spontaneous hematogenous osteomyelitis, and compared to gene expression in liver tissue. Furthermore, immunohistochemical (IHC) staining of the APP complement component C3 (C3) was performed on the porcine osteomyelitis lesions together with material from human patients with chronic osteomyelitis. In the porcine bone samples a local upregulation of the expression of several APP genes, including serum amyloid A (SAA) and C3, was observed during infection. In the liver, only C-reactive protein (CRP) and Inter-Alpha-Trypsin Inhibitor Heavy Chain 4 were significantly upregulated. Serum concentrations of CRP, SAA and haptoglobin were only upregulated at day 5 in infected animals of the IAO model. This indicates a limited systemic response to osteomyelitis. Similar numbers of positive IHC stained C3 leukocytes were found in human and porcine bone samples with chronic osteomyelitis, indicating a high transcriptional value of porcine models of osteomyelitis. The local upregulation of APPs could potentially be used for diagnosing osteomyelitis. [ABSTRACT FROM AUTHOR]
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- 2020
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556. Non-BRCA1/BRCA2 high-risk familial breast cancers are not associated with a high prevalence of BRCAness.
- Author
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Andersen LVB, Larsen MJ, Davies H, Degasperi A, Nielsen HR, Jensen LA, Kroeldrup L, Gerdes AM, Lænkholm AV, Kruse TA, Nik-Zainal S, and Thomassen M
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- Humans, Female, Prevalence, Mutation, BRCA2 Protein genetics, Genes, BRCA2, Breast Neoplasms epidemiology, Breast Neoplasms genetics
- Abstract
Background: Familial breast cancer is in most cases unexplained due to the lack of identifiable pathogenic variants in the BRCA1 and BRCA2 genes. The somatic mutational landscape and in particular the extent of BRCA-like tumour features (BRCAness) in these familial breast cancers where germline BRCA1 or BRCA2 mutations have not been identified is to a large extent unknown., Methods: We performed whole-genome sequencing on matched tumour and normal samples from high-risk non-BRCA1/BRCA2 breast cancer families to understand the germline and somatic mutational landscape and mutational signatures. We measured BRCAness using HRDetect. As a comparator, we also analysed samples from BRCA1 and BRCA2 germline mutation carriers., Results: We noted for non-BRCA1/BRCA2 tumours, only a small proportion displayed high HRDetect scores and were characterized by concomitant promoter hypermethylation or in one case a RAD51D splice variant previously reported as having unknown significance to potentially explain their BRCAness. Another small proportion showed no features of BRCAness but had mutationally active tumours. The remaining tumours lacked features of BRCAness and were mutationally quiescent., Conclusions: A limited fraction of high-risk familial non-BRCA1/BRCA2 breast cancer patients is expected to benefit from treatment strategies against homologue repair deficient cancer cells., (© 2023. The Author(s).)
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- 2023
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557. Review of gestational diabetes mellitus effects on vascular structure and function.
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Jensen LA, Chik CL, and Ryan EA
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- Adult, Biomarkers blood, Blood Glucose metabolism, Body Mass Index, Diabetes, Gestational blood, Diabetes, Gestational pathology, Diabetes, Gestational physiopathology, Diabetic Angiopathies blood, Diabetic Angiopathies pathology, Diabetic Angiopathies physiopathology, Female, Humans, Insulin blood, Insulin Resistance, Middle Aged, Obesity complications, Obesity diagnosis, Pregnancy, Risk Assessment, Risk Factors, Diabetic Angiopathies etiology, Endothelial Cells metabolism, Endothelial Cells pathology, Endothelium, Vascular metabolism, Endothelium, Vascular pathology, Endothelium, Vascular physiopathology
- Abstract
Vascular dysfunction has been described in women with a history of gestational diabetes mellitus. Furthermore, previous gestational diabetes mellitus increases the risk of developing Type 2 diabetes mellitus, a risk factor for cardiovascular disease. Factors contributing to vascular changes remain uncertain. The aim of this review was to summarize vascular structure and function changes found to occur in women with previous gestational diabetes mellitus and to identify factors that contribute to vascular dysfunction. A systematic search of electronic databases yielded 15 publications from 1998 to March 2014 that met the inclusion criteria. Our review confirmed that previous gestational diabetes mellitus contributes to vascular dysfunction, and the most consistent risk factor associated with previous gestational diabetes mellitus and vascular dysfunction was elevated body mass index. Heterogeneity existed across studies in determining the relationship of glycaemic levels and insulin resistance to vascular dysfunction., (© The Author(s) 2016.)
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- 2016
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558. Women with a history of gestational diabetes on long-term follow up have normal vascular function despite more dysglycemia, dyslipidemia and adiposity.
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Ajala O, Jensen LA, Ryan E, and Chik C
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- Adiposity, Adult, Blood Glucose analysis, Body Mass Index, C-Reactive Protein analysis, Case-Control Studies, Diabetes Mellitus, Type 2 blood, Female, Follow-Up Studies, Glucose Tolerance Test, Humans, Lipids blood, Postpartum Period, Pregnancy, Risk Factors, Waist-Hip Ratio, Diabetes, Gestational epidemiology, Dyslipidemias epidemiology, Insulin Resistance, Obesity epidemiology
- Abstract
Aims: Previous gestational diabetes (GDM) is a risk factor for type 2 diabetes and increased metabolic risk, but the link with vascular dysfunction is not clear. This study examined vascular function in women 4-10 years after a diagnosis of GDM who had a normal oral glucose tolerance test (OGTT) in the first postpartum year., Methods: We studied 90 women with a history of GDM and 59 age-matched controls, examining differences in insulin resistance as measured by the Homeostatic Model Assessment (HOMA-IR) and glucose responses during an OGTT, adiposity, lipid profile and C-reactive protein (CRP). Using pulse wave analysis, we also measured cardiac function, vascular compliance, and systemic vascular resistance., Results: Women with a history of GDM had higher measures of adiposity (body mass index 28.9 ± 6.5 vs. 26.6 ± 6.9 kg/m(2), P=0.04, waist-hip ratio 0.85 ± 0.06 vs. 0.79 ± 0.07, P<0.001), dyslipidemia (LDL cholesterol 2.78 ± 0.64 vs. 2.41 ± 0.56 mmol/L, P<0.001, total cholesterol: HDL cholesterol 3.93 ± 1.2 vs. 3.21 ± 0.82 mmol/L, P<0.001) and abnormal glucose metabolism (50% vs. 12%, P<0.001). However, there was no difference in CRP, HOMA-IR, or measures of cardiovascular function including pulse rate, pulse pressure, mean arterial pressure, cardiac output, systemic vascular resistance, small and large artery elasticity index. After controlling for adiposity, blood pressure, lipids and CRP, glycemic status did not contribute to vascular function., Conclusion: Despite a higher incidence of adiposity, dyslipidemia, and impaired glycemia, women with a history of GDM who had a normal postpartum OGTT did not have impaired vascular function 4-10 years postpartum, when compared to healthy controls., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2015
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