| 1. |
- Moschella, P. S., et al.
(författare)
-
Low-crested coastal defence structures as artificial habitats for marine life: Using ecological criteria in design
- 2005
-
Ingår i: Coastal Engineering. - : Elsevier BV. - 0378-3839. ; 52:10-11, s. 1053-1071
-
Tidskriftsartikel (refereegranskat)abstract
- Coastal defence structures to protect sedimentary coastlines from erosion and flooding are increasingly common throughout Europe. They will become more widespread over the next 10-30 years in response to rising and stormier seas and accelerating economic development of the coastal zone. Building coastal defences results in the loss and fragmentation of sedimentary habitats and their replacement by artificial rocky habitats that become colonised by algae and marine animals. The engineering design and construction of these structures have received considerable attention. However, the ecological consequences of coastal defences have been less extensively investigated. Furthermore, due to their rapid proliferation, there is a growing need to understand the role of these man-made habitats in the coastal ecosystems in order to implement impact minimisation and/or mitigation measures. As part of the DELOS project, targeted studies were carried out throughout Europe to assess the ecological similarity of low-crested coastal defence structures (LCS) to natural rocky shores and to investigate the influence of LCS design features on the colonising marine epibiota. LCSs can be considered as a relatively poor surrogate of natural rocky shores. Epibiotic communities were qualitatively similar to those on natural rocky shores as both habitats are regulated by the same physical and biological factors. However, there were quantitative differences in the diversity and abundance of epibiota on artificial structures. Typically, epibiotic assemblages were less diverse than rocky shore communities. Also, LCSs offered less structurally complex habitats for colonisation and in some locations experienced higher disturbance than natural shores. We propose several criteria that can be integrated into the design and construction of LCSs to minimise ecological impacts and allow targeted management of diversity and natural living resources. (c) 2005 Elsevier B.V. All rights reserved.
|
|
| 2. |
- Airoldi, L., et al.
(författare)
-
An ecological perspective on the deployment and design of low-crested and other hard coastal defence structures
- 2005
-
Ingår i: Coastal Engineering. - : Elsevier BV. - 0378-3839. ; 52:10-11, s. 1073-1087
-
Tidskriftsartikel (refereegranskat)abstract
- Coastal areas play a crucial role in the economical, social and political development of most countries; they support diverse and productive coastal ecosystems that provide valuable goods and services. Globally flooding and coastal erosion represent serious threats along many coastlines, and will become more serious as a consequence of human-induced changes and accelerated sea-level rise. Over the past century, hard coastal defence structures have become ubiquitous features of coastal landscapes as a response to these threats. The proliferation of defence works can affect over half of the shoreline in some regions and results in dramatic changes to the coastal environment. Surprisingly little attention has been paid to the ecological consequences of coastal defence. Results from the DELOS (Environmental Design of Low Crested Coastal Defence Structures, EVK3-CT-2000-00041) project indicate that the construction of coastal defence structures will affect coastal ecosystems. The consequences can be seen on a local scale, as disruption of surrounding soft-bottom environments and introduction of new artificial hard-bottom habitats, with consequent changes to the native assemblages of the areas. Proliferation of coastal defence structures can also have critical impacts on regional species diversity, removing isolating barriers, favouring the spread of non-native species and increasing habitat heterogeneity. Knowledge of the environmental context in which coastal defence structures are placed is fundamental to an effective management of these structures as, while there are some general consequences of such construction, many effects are site specific. Advice is provided to meet specific management goals, which include mitigating specific impacts on the environment, such as minimising changes to surrounding sediments, spread of exotic species or growth of nuisance species, and/or enhancing specific natural resources, for example enhancing fish recruitment or promoting diverse assemblages for eco-tourism. The DELOS project points out that the downstream effects of defence structures on coastal processes and regional-scale impacts on biodiversity necessitate planning and management at a regional (large coastline) scale. To effectively understand and manage coastal defences, environmental management goals must be clearly stated and incorporated into the planning, construction, and monitoring stages. (c) 2005 Elsevier B.V. All rights reserved.
|
|
| 3. |
- Bergemalm, Daniel, 1977-, et al.
(författare)
-
Changes in the spinal cord proteome of an amyotrophic lateral sclerosis murine model determined by differential in-gel electrophoresis
- 2009
-
Ingår i: Molecular and cellular proteomics. - : The American Society for Biochemistry and Molecular Biology,Inc. - 1535-9484. ; 8:6, s. 1306-1317
-
Tidskriftsartikel (refereegranskat)abstract
- Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by loss of motor neurons resulting in progressive paralysis. To date, more than 140 different mutations in the gene encoding CuZn-superoxide dismutase (SOD1) have been associated with ALS. Several transgenic murine models exist in which various mutant SOD1s are expressed. We have used differential in-gel electrophoresis (DIGE) to analyze the changes in the spinal cord proteome induced by expression of the unstable SOD1 truncation mutant G127insTGGG (G127X) in mice. Unlike mutants used in most other models, G127X lacks SOD activity and is present at low levels, thus reducing the risk of overexpression artifacts. The mice were analyzed at their peak body weights, just before onset of symptoms. Variable importance plot (VIP) analysis showed that 420 of 1,800 detected protein spots contributed significantly to the differences between the groups. By MALDI-TOF MS analysis, 54 proteins were identified. One spot was found to be a covalently linked mutant SOD1 dimer, apparently analogous to SOD1 immunoreactive bands migrating at double the molecular weight of SOD1 monomers previously detected in humans and mice carrying mutant SOD1s and in sporadic ALS cases. Analyses of affected functional pathways, and the subcellular representation of alterations suggest that the toxicity exerted by mutant SODs induces oxidative stress and affects mitochondria, cellular assembly/organization, and protein degradation.
|
|
| 4. |
- Bergemalm, Daniel, 1977-, et al.
(författare)
-
Overloading of stable and exclusion of unstable human superoxide dismutase-1 variants in mitochondria of murine amyotrophic lateral sclerosis models
- 2006
-
Ingår i: Journal of Neuroscience. - : Society for Neuroscience. - 0270-6474 .- 1529-2401. ; 26:16, s. 4147-4154
-
Tidskriftsartikel (refereegranskat)abstract
- Mutants of human superoxide dismutase-1 (hSOD1) cause amyotrophic lateral sclerosis (ALS), and mitochondria are thought to be primary targets of the cytotoxic action. The high expression rates of hSOD1s in transgenic ALS models give high levels of the stable mutants G93A and D90A as well as the wild-type human enzyme, significant proportions of which lack Cu and the intrasubunit disulfide bond. The endogenous murine SOD1 (mSOD1) also lacks Cu and is disulfide reduced but is active and oxidized in mice expressing the low-level unstable mutants G85R and G127insTGGG. The possibility that the molecular alterations may cause artificial loading of the stable hSOD1s into mitochondria was explored. Approximately 10% of these hSOD1s were localized to mitochondria, reaching levels 100-fold higher than those of mSOD1 in control mice. There was no difference between brain and spinal cord and between stable mutants and the wild-type hSOD1. mSOD1 was increased fourfold in mitochondria from high-level hSOD1 mice but was normal in those with low levels, suggesting that the Cu deficiency and disulfide reduction cause mitochondrial overloading. The levels of G85R and G127insTGGG mutant hSOD1s in mitochondria were 100- and 1000-fold lower than those of stable mutants. Spinal cords from symptomatic mice contained hSOD1 aggregates covering the entire density gradient, which could contaminate isolated organelle fractions. Thus, high hSOD1 expression rates can cause artificial loading of mitochondria. Unstable low-level hSOD1s are excluded from mitochondria, indicating other primary locations of injury. Such models may be preferable for studies of ALS pathogenesis.
|
|
| 5. |
- Dahlin, Andreas, 1980, et al.
(författare)
-
High-Resolution Microspectroscopy of Plasmonic Nanostructures for Miniaturized Biosensing
- 2009
-
Ingår i: Analytical Chemistry. - : American Chemical Society. - 0003-2700 .- 1520-6882. ; 81:16, s. 6572-6580
-
Tidskriftsartikel (refereegranskat)abstract
- In this article, we demonstrate how to perform microscale spectroscopy of plasmonic nanostructures in order to minimize the noise when determining the resonance peak wavelength. This is accomplished using an experimental setup containing standard optical components mounted on an ordinary light microscope. We present a detailed comparison between extinction spectroscopy in transmission mode and scattering spectroscopy under dark field illumination, which shows that extinction measurements provide higher signal-to-noise in almost all situations. Furthermore, it is shown that rational selection of nanostructure, hardware components, and data analysis algorithms enables tracking of the particle plasmon resonance wavelength from a 10 mu m x 50 mu m area with a resolution of 10(-3) nm in transmission mode. We investigate how the temporal resolution, which can be improved down to 17 Ins, affects, the noise characteristics. In addition, we show how data can be acquired from an area as small as 2 mu m x 10 mu m (similar to 240 particles) at the expense of higher noise on longer time scales. In comparison with previous work on macroscopic sensor designs, this represents a sensor miniaturization of 5 orders of magnitude, without any loss in signal-to-noise performance. As a model system, we illustrate biomolecular detection using gold nanodisks prepared by colloidal lithography. The microextinction measurements of nanodisks described here provide detection of protein surface coverages as low as 40 pg/cm(2) (less than0.1% of saturated binding). In fact, the miniaturized system provides a detection limit in terms of surface coverage comparable to state of the art macroscopic sensors, while simultaneously being as close to single protein molecule detection as sensors based on a single nanoparticle.
|
|
| 6. |
- Jonsson, Andreas P., et al.
(författare)
-
Disulphide-reduced superoxide dismutase-1 in CNS of transgenic amyotrophic lateral sclerosis models
- 2006
-
Ingår i: Brain. - : Oxford University Press. - 0006-8950 .- 1460-2156. ; 129:Pt 2, s. 451-644
-
Tidskriftsartikel (refereegranskat)abstract
- Mutant forms of superoxide dismutase-1 (SOD1) cause amyotrophic lateral sclerosis (ALS) by an unknown noxious mechanism. Using an antibody against a novel epitope in the G127insTGGG mutation, mutant SOD1 was studied for the first time in spinal cord and brain of an ALS patient. The level was below 0.5% of the SOD1 level in controls. In corresponding transgenic mice the content of mutant SOD1 was also low, although it was enriched in spinal cord and brain compared with other tissues. In the mice the misfolded mutant SOD1 aggregated rapidly and 20% occurred in steady state as detergent-soluble protoaggregates. The misfolded SOD1 and the protoaggregates form, from birth until death, a potentially noxious burden that may induce the motor neuron injury. Detergent-resistant aggregates, as well as inclusions of mutant SOD1 in motor neurons and astrocytes, accumulated in spinal cord ventral horns of the patient and mice with terminal disease. The inclusions and aggregates may serve as terminal markers of long-term assault by misfolded SOD1 and protoaggregates.
|
|
| 7. |
|
|
| 8. |
- Jonsson, Andreas P., et al.
(författare)
-
Motor neuron disease in mice expressing the wild type-like D90A mutant superoxide dismutase-1
- 2006
-
Ingår i: Journal of Neuropathology and Experimental Neurology. - : Oxford University Press (OUP). - 0022-3069 .- 1554-6578. ; 65:12, s. 1126-1136
-
Tidskriftsartikel (refereegranskat)abstract
- Mutant human CuZn-superoxide dismutases (hSOD1s) cause amyotrophic lateral sclerosis (ALS). The most common mutation is the wild type-like D90A and to explore its properties, transgenic mice were generated and compared with mice expressing wild-type hSOD1. D90A hSOD1 was both in vivo in mice and in vitro under denaturing conditions nearly as stable as the wild-type human enzyme. It appeared less toxic than other tested mutants, but mice homozygous for the transgene insertion developed a fatal motor neuron disease. In these mice, the disease progression was slow and there were bladder disturbances similar to what is found in human ALS cases homozygous for the D90A mutation. The homozygous D90A mice accumulated detergent-resistant hSOD1 aggregates in spinal cords, and abundant hSOD1 inclusions and vacuoles were seen in the ventral horns. Mice expressing wild-type hSOD1 at a comparable rate showed similar pathologic changes but less and later. Hemizygous D90A mice showed even milder alterations. At 600 days, the wild-type hSOD1 transgenic mice had lost more ventral horn neurons than hemizygous D90A mice (38% vs 31% p < 0.01). Thus, wild-type hSOD1 shows a significant neurotoxicity in the spinal cord, that is less than equal but more than half as large as that of D90A mutant enzyme.
|
|
| 9. |
|
|
| 10. |
- Jonsson, P. Andreas, 1973-
(författare)
-
Superoxide dismutase 1 and amyotrophic lateral sclerosis
- 2005
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease affecting motor neurons in the spinal cord, brain stem and motor cortex, leading to paralysis, respiratory failure and death. In about 5% of ALS cases, the disease is associated with mutations in the CuZn-superoxide dismutase (hSOD1) gene. As a rule, ALS caused by hSOD1 mutations is inherited dominantly and the mutant hSOD1s cause ALS by the gain of a noxious property. The present study focused on two hSOD1 mutations with widely differing characters. In Scandinavia, ALS caused by the D90A mutation is inherited in a recessive pattern. Elsewhere, families with dominant inheritance have been found. The properties of D90A mutant hSOD1 are very similar to those of the wild-type protein. The G127insTGGG (G127X) mutation causes a 21 amino acid C-terminal truncation which probably results in an unstable protein. The aim of this thesis was to generate transgenic mice expressing D90A and G127X mutant hSOD1s and to compare these mice with each other and with mice expressing other mutant hSOD1s, in search of a common noxious property. The findings were also compared with the results from studies of human CNS tissue. The cause of the different inheritance patterns associated with D90A mutant hSOD1 was investigated by analyzing erythrocytes from heterozygous individuals from dominant and recessive pedigrees. There was no evidence that a putative protective factor in recessive pedigrees acts by down-regulating the synthesis of D90A mutant hSOD1. In cerebrospinal fluid, there was no difference in hSOD1 content between homozygous D90A patients, ALS patients without hSOD1 mutations and controls. hSOD1 cleaved at the N-terminal end was found in both controls and D90A patients, but the proportion was significantly larger in the latter group. This indicates a difference in degradation routes between mutant and wild-type hSOD1. Both D90A and G127X transgenic mice develop an ALS-like phenotype. Similar to humans, the levels of D90A protein were high. The levels of G127X hSOD1 were very low in the tissues but enriched in the CNS. Similarly, in an ALS patient heterozygous for G127X hSOD1, the levels of the mutant protein were overall very low, but highest in affected CNS areas. Despite the very different levels of mutant hSOD1, both D90A and G127X transgenic mice developed similar levels of detergent-resistant aggregates in the spinal cord when terminally ill. Surprisingly, mice overexpressing wild-type hSOD1 also developed detergent-resistant aggregates, although less and later. Most of the hSOD1 in the CNS of transgenic mice was inactive due to deficient copper charging or because of reduced affinity for the metal. The stabilizing intrasubunit disulfide bond of hSOD1 was partially or completely absent in the different hSOD1s. Both these alterations could increase the propensity of mutant hSOD1s to misfold and form aggregates. The results presented here suggest that the motor neuron degeneration caused by mutant hSOD1s may be attributable to long-term exposure to misfolded, aggregation-prone, disulfide-reduced hSOD1s and that the capacity to degrade such hSOD1s is lower in susceptible CNS areas compared with other tissues. The data also suggest that wild-type hSOD1 has the potential to participate in the pathogenesis of sporadic ALS.
|
|
