| 1. |
- Grönlund, Eric, 1987-, et al.
(författare)
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Robust treatment planning of dose painting for prostate cancer based on ADC-to-Gleason score mappings : what is the potential to increase the tumor control probability?
- 2021
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Ingår i: Acta Oncologica. - : Taylor & Francis. - 0284-186X .- 1651-226X. ; 60:2, s. 199-206
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Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose The aim of this study was to evaluate the potential to increase the tumor control probability (TCP) with ‘dose painting by numbers’ (DPBN) plans optimized in a treatment planning system (TPS) compared to uniform dose plans. The DPBN optimization was based on our earlier published formalism for prostate cancer that is driven by dose-responses of Gleason scores mapped from apparent diffusion coefficients (ADC).Material and MethodsFor 17 included patients, a set of DPBN plans were optimized in a TPS by maximizing the TCP for an equal average dose to the prostate volume (CTVT) as for a conventional uniform dose treatment. For the plan optimizations we applied different photon energies, different precisions for the ADC-to-Gleason mappings, and different CTVT positioning uncertainties. The TCP increasing potential was evaluated by the DPBN efficiency, defined as the ratio of TCP increases for DPBN plans by TCP increases for ideal DPBN prescriptions (optimized without considering radiation transport phenomena, uncertainties of the CTVT positioning, and uncertainties of the ADC-to-Gleason mapping).ResultsThe median DPBN efficiency for the most conservative planning scenario optimized with a low precision ADC-to-Gleason mapping, and a positioning uncertainty of 0.6 cm was 10%, meaning that more than half of the patients had a TCP gain of at least 10% of the TCP for an ideal DPBN prescription. By increasing the precision of the ADC-to-Gleason mapping, and decreasing the positioning uncertainty the median DPBN efficiency increased by up to 40%.ConclusionsTCP increases with DPBN plans optimized in a TPS were found more likely with a high precision mapping of image data into dose-responses and a high certainty of the tumor positioning. These findings motivate further development to ensure precise mappings of image data into dose-responses and to ensure a high spatial certainty of the tumor positioning when implementing DPBN clinically.
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| 2. |
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| 3. |
- Berglund, Åsa, 1978-, et al.
(författare)
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Effects of reduced lead deposition on Pied flycatcher (Ficedula hypoleuca) : tracing exposure routes using stable lead Isotopes
- 2009
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Ingår i: Environmental Science and Technology. - : American Chemical Society. - 0013-936X .- 1520-5851. ; 43:1, s. 208-213
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Tidskriftsartikel (refereegranskat)abstract
- To what extent the lead burden of birds living in strongly contaminated ecosystems is responding to decreased atmospheric lead deposition is not well known. In this study, we measured lead concentrations and stable lead isotope ratios (206Pb/207Pb and 208Pb/207Pb) in liver and feces from pied flycatcher nestlings (Ficedula hypoleuca) along a 90 km pollution gradient from the Rönnskär smelter in northern Sweden. Changes in lead concentration in the birds from 1984 to 2006 were used for assessing the recovery of the environment following reduced lead emissions at the smelter. The 206Pb/207Pb and 208Pb/207Pb ratios were used to identify lead sources to the birds. Lead concentrations in liver and feces have decreased since the 1980s, typically by 9−15% (liver) and 18−40% (feces) as a result of a 98% emission reduction. This relatively weak recovery is explained by a transfer of old lead contaminants accumulated in soil to the birds via their prey, which was evident by a 206Pb/207Pb ratio in liver tissue (1.15 ± 0.01) that overlapped with the ratio in ants (1.16 ± 0.01) and organic soil horizon (1.17 ± 0.01) rather than the current atmospheric lead pollution (1.11 ± 0.01). Our findings suggest that insectivorous birds living around smelters may remain contaminated decades after ceased emissions.
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| 4. |
- Berglund, Åsa, 1978-, et al.
(författare)
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Lead exposure and biological effects in pied flycatchers (Ficedula hypoleuca) before and after the closure of a lead mine in northern Sweden.
- 2010
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Ingår i: Environmental Pollution. - : Elsevier Ltd. - 0269-7491 .- 1873-6424. ; 158:5, s. 1368-75
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Tidskriftsartikel (refereegranskat)abstract
- Mining activities affect the surrounding environment by increasing exposure to metals. In this study, metal accumulation and its effects on reproduction and health of pied flycatcher (Ficedula hypoleuca) nestlings were monitored before and up to five years after a lead mine and enrichment plant closed down. The lead concentration in moss, nestling blood, liver and feces all indicated decreased lead exposure by at least 31% after closure, although only blood lead decreased significantly. Although the birds responded fairly well to the changed atmospheric deposition (based on moss samples), concentrations were still higher compared with birds in a reference area, and breeding was affected at the mine (smaller clutches and higher mortality). Surviving nestlings suffered from lower hemoglobin levels, mean cell hemoglobin concentrations and inhibited delta-aminolevulinic acid dehydratase activity. Lead poisoning contributed to poor health and adverse reproductive effects, but other factors (e.g. increased parasitic load) probably also affected the birds.
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| 5. |
- Berglund, Åsa, 1978-, et al.
(författare)
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Oxidative stress in pied flycatcher (Ficedula hypoleuca) nestlings from metal contaminated environments in northern Sweden.
- 2007
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Ingår i: Environmental Research. - : Elsevier BV. - 0013-9351 .- 1096-0953. ; 105:3, s. 330-339
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Tidskriftsartikel (refereegranskat)abstract
- Metals have been shown to induce oxidative stress in animals. One of the most metal polluted terrestrial environments in Sweden is the surroundings of a sulfide ore smelter plant located in the northern part of the country. Pied flycatcher nestlings (Ficedula hypoleuca) that grew up close to the industry had accumulated amounts of arsenic, cadmium, mercury, lead, iron and zinc in their liver tissue. The aim of this study was to investigate if pied flycatcher nestlings in the pollution gradient of the industry were affected by oxidative stress using antioxidant molecules and enzyme activities. The antioxidant assays were also evaluated in search for useful biomarkers in pied flycatchers. This study indicated that nestlings in metal contaminated areas showed signs of oxidative stress evidenced by up regulated hepatic antioxidant defense given as increased glutathione reductase (GR) and catalase (CAT) activities and slightly but not significantly elevated lipid peroxidation and glutathione-S-transferase (GST) activities. Stepwise linear regression indicated that lipid peroxidation and CAT activities were influenced mostly by iron, but iron and lead influenced the CAT activity to a higher degree. Positive relationships were found between GST and lead as well as GR activities and cadmium. We conclude that GR, CAT, GST activities and lipid peroxidation levels may function as useful biomarkers for oxidative stress in free-living pied flycatcher nestlings exposed to metal contaminated environments.
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| 6. |
- Berglund, Åsa, 1978-
(författare)
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Responses to reduced industrial metal emissions : An ecotoxicological study on Pied Flycatcher (Ficedula hypoleuca, Aves)
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Metals have been used by humans for thousands of years, and this has resulted in increased concentrations in the biosphere. The environment around point-sources, such as mines and smelters, are of particular concern, as metals may accumulate to high concentrations, and potentially reach levels toxic to the local flora and fauna. This thesis focuses on the effects on pied flycatcher populations of two such point-sources, a lead mine and enrichment plant, and a sulfide ore smelter. Mining activities at the lead mine ceased in 2001 and pied flycatcher populations were assessed before and after the closure. At the sulfide ore smelter, pied flycatchers were studied during the 1980s. Since then, the metal emissions to air from the smelter (e.g. arsenic, cadmium, copper, mercury, lead and zinc) have been greatly reduced (by 93 – 99%).Pied flycatchers from these two contaminated environments differed in their responses to reduced atmospheric deposition. At the mine site, nestling responses reflected the reduced atmospheric deposition and less lead accumulated in their tissues. However, lead levels were still high enough to cause negative effects on blood status (δ-aminolevulinic acid dehydratase [ALAD], hemoglobin [Hb], hematocrit [ht], and mean cell hemoglobin concentration) and reproduction (reduced clutch size, increased mortality and reduced breeding success), as was observed when the mine was in operation. Along the pollution gradient away from the smelter, nestling concentrations reflected the metal load in the soil pool, accumulating over time, rather than the atmospheric deposition. This resulted in only a minor response to decreased metal deposition (slightly reduced liver lead concentrations at 3.5 – 90 km from the smelter). This suggests that in environments with highly polluted soils, decreased inputs of atmospheric metal deposition have only minor impacts, and recovery from contamination should not be expected within decades.The high metal concentrations in the vicinity of the smelter contributed to poorer blood status (ALAD, Hb and ht), induced oxidative damage and defenses, and decreased reproduction (increased mortality and reduced breeding success). There were only minor improvements in blood and reproductive variables at 3.5 km from the smelter.
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| 7. |
- Berglund, Åsa, et al.
(författare)
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Slow improvements of metal exposure, health- and breeding conditions of pied flycatchers (Ficedula hypoleuca) after decreased industrial heavy metal emissions
- 2011
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Ingår i: Science of the Total Environment. - Amsterdam : Elsevier. - 0048-9697 .- 1879-1026. ; 409:20, s. 4326-4334
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Tidskriftsartikel (refereegranskat)abstract
- The environment around metal industries, such as smelters, is often highly contaminated due to continuous deposition of metals. We studied nest box breeding populations of pied flycatchers (Ficedula hypoleuca) in a well-studied pollution gradient from a sulfide ore smelter in Northern Sweden, after reduced aerial metal emissions (by 93-99%) from the smelter. The deposition of arsenic, cadmium, copper and zinc (based on moss samples) reflected the reduced emissions fairly well. However, nestling pied flycatchers had similar concentrations of these elements and mercury in tissues (bone, liver and blood) and feces in the 2000s, as in the 1980s, when the emissions were substantially higher. The exposure to high metal concentrations in the close vicinity of the smelter resulted in inhibited ALAD activities, depressed hemoglobin and hematocrit levels and increased mortality of nestlings. Our results indicate that in the highly contaminated environment around the smelter, nestlings reflected the slowly cycling soil pool, rather than the atmospheric deposition, and the concentration in soils plays an important role for the response of pied flycatchers to reduced atmospheric deposition.
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| 8. |
- Berglund, Åsa, 1978-, et al.
(författare)
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Slow improvements of metal exposure, health- and breeding conditions of pied flycatchers (Ficedula hypoleuca) after decreased industrial heavy metal emissions
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The environment around metal industries, such as smelters, is often highly contaminated due to continuous deposition of metals. We studied nest box breeding populations of pied flycatchers (Ficedula hypoleuca) in a well-studied pollution gradient from a sulfide ore smelter in Northern Sweden, after reduced aerial metal emissions (by 93 – 99%) from the smelter. The deposition of As, Cd, Cu and Zn (based on moss samples) reflected the reduced emissions fairly well. However, nestling pied flycatchers had similar concentrations of these elements and Hg in tissue (bone, liver and blood) and feces in the 2000s, as in the 1980s, when the emissions were substantially higher. The slow improvement of metal accumulation in birds was explained by a food web transfer of metals mainly from the highly polluted soils, and it was concluded that nestlings reflected the slowly cycling soil pool, rather than the current atmospheric deposition. The exposure to high metal concentrations in the close vicinity of the smelter resulted in inhibited ALAD activities, depressed hemoglobin and hematocrit levels and increased mortality of nestlings. Our results indicate that in metal contaminated environments, the concentration in soils plays an important role for the response of pied flycatchers to reduced atmospheric deposition.
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| 9. |
- Both, C., et al.
(författare)
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Large-scale geographical variation confirms that climate change causes birds to lay earlier
- 2004
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Ingår i: Proceedings of the Royal Society of London Series B-Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 271:1549, s. 1657-1662
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Tidskriftsartikel (refereegranskat)abstract
- Advances in the phenology of organisms are often attributed to climate change, but alternatively, may reflect a publication bias towards advances and may be caused by environmental factors unrelated to climate change. Both factors are investigated using the breeding dates of 25 long-term studied populations of Ficedula flycatchers across Europe. Trends in spring temperature varied markedly between study sites, and across populations the advancement of laying date was stronger in areas where the spring temperatures increased more, giving support to the theory that climate change causally affects breeding date advancement.
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| 10. |
- Both, C., et al.
(författare)
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Pied Flycatchers Ficedula hypoleuca travelling from Africa to breed in Europe: differential effects of winter and migration conditions on breeding date
- 2006
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Ingår i: ARDEA. - 0373-2266 .- 2213-1175. ; 94:3, s. 511-525
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Tidskriftsartikel (refereegranskat)abstract
- In most bird species there is only a short time window available for optimal breeding due to variation in ecological conditions in a seasonal environment. Long-distance migrants must travel before they start breeding, and conditions at the wintering grounds and during migration may affect travelling speed and hence arrival and breeding dates. These effects are to a large extent determined by climate variables such as rainfall and temperature, and need to be identified to predict how well species can adapt to climate change. In this paper we analyse effects of vegetation growth on the wintering grounds and sites en route on the annual timing of breeding of 17 populations of Pied Flycatchers Ficedula hypoleuca studied between 1982–2000. Timing of breeding was largely correlated with local spring temperatures, supplemented by striking effects of African vegetation and NAO. Populations differed in the effects of vegetation growth on the wintering grounds, and on their northern African staging grounds, as well as ecological conditions in Europe as measured by the winter NAO. In general, early breeding populations (low altitude, western European populations) bred earlier in years with more vegetation in the Northern Sahel zone, as well as in Northern Africa. In contrast, late breeding populations (high altitude and northern and eastern populations) advanced their breeding dates when circumstances in Europe were more advanced (high NAO). Thus, timing of breeding in most Pied Flycatcher populations not only depends upon local circumstances, but also on conditions encountered during travelling, and these effects differ across populations dependent on the timing of travelling and breeding.
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