Oxygen and carbon isoscapes for the Baltic Sea: Testing their applicability in fish migration studies

Conventional tags applied to individuals have been used to investigate animal movement, but these methods require tagged individuals be recaptured. Maps of regional isotopic variability known as “isoscapes” offer potential for various applications in migration research without tagging wherein isotope values of tissues are compared to environmental isotope values. In this study, we present the spatial variability in oxygen () and dissolved inorganic carbon (δ¹³C_DIC) isotope values of Baltic Sea water. We also provide an example of how these isoscapes can reveal locations of individual animal via spatial probability surface maps, using the high‐resolution salmon otolith isotope data from salmon during their sea‐feeding phase in the Baltic Sea. A clear latitudinal and vertical gradient was found for both and δ¹³C_DIC values. The difference between summer and winter in the Baltic Sea values was only slight, whereas δ¹³C_DIC values exhibited substantial seasonal variability related to algal productivity. Salmon otolith δ¹⁸O_oto and δ¹³C_oto values showed clear differences between feeding areas and seasons. Our example demonstrates that dual isotope approach offers great potential for estimating probable fish habitats once issues in model parameterization have been resolved.     

Fluxes of N2O,CH4 and CO2 on afforested boreal agricultural soils

After drainage of natural boreal peatlands, the decomposition of organic matter increases and peat soil may turn into a net source of CO₂ and N₂O, whereas CH₄ emission is known to decrease. Afforestation is a potential mitigation strategy to reduce greenhouse gas emission from organic agricultural soils. A static chamber technique was used to evaluate the fluxes of CH₄, N₂O and CO₂ from three boreal organic agricultural soils in western Finland, afforested 1, 6 or 23 years before this study. The mean emissions of CH₄ and N₂O during the growing seasons did not correlate with the age of the tree stand. All sites were sources of N₂O. The highest daily N₂O emission during the growing season, measured in the oldest site, was as high as 29 mg N₂O m^–2d^–1. In general, organic agricultural soils are sinks for methane. Here, the oldest site acted as a small sink for methane, whereas the two youngest afforested organic soils were sources for methane with maximum emission rates (up to 154 mg m^–2d^–1) similar to those reported for minerogenous natural peatlands. Soil respiration rates decreased with the age of the forest. The high soil respiration in the younger sites, probably resulted from the high biomass production of herbs, could create soil anaerobiosis and increase methane production. Our results show that afforestation of agricultural peat soils does not abruptly terminate the N₂O emissions during the first two decades, and afforestation can even enhance methane emission for a few years. The carbon accumulation in the developing tree stand can partly compensate the carbon loss from soil.     

Governing the Interplay between Industrial Ecosystems and Environmental Regulation

Many scholars of industrial ecology have focused on the institutional and organizational challenges of building and maintaining regional industrial symbiosis through the synergistic integration of material and energy flows. Despite the promise that these intellectual developments hold for the future dematerialization of industrial production, they rarely address the actual regulatory obstacles of turning wastes into raw materials. In this article we introduce a potential future industrial symbiosis around the Gulf of Bothnia between Finland and Sweden, and assess the regulatory bottlenecks related to waste by‐product consideration. We find that although the Gulf of Bothnia region has technological and economic potential for industrial symbiosis, the regulatory support for this is insufficient. We suggest a common pool resource‐based governance system that could utilize market and regulatory mechanisms in a regional‐level cross‐border system of governance. Importantly, the suggested governance system would protect the users of potential raw materials from unpredictable waste regulation, market risks related to large‐scale material flows, and societal risks of hazardous waste treatment.     

Endogenous extracellular purine nucleotides redirect α2-adrenoceptor signaling

Many receptors coupled to inhibitory G_o/G_i-type G proteins often also produce stimulatory signals like Ca²⁺ mobilisation. When expressed in CHO cells the α₂-adrenoceptor subtypes α_2A, α_2B and α_2C mobilised Ca²⁺. These responses were strongly reduced by the P_2Y-purinoceptor antagonist suramin. A large proportion of the total pool of purine nucleotides was found extracellularly. Removal of extracellular nucleotides with apyrase or by constant perfusion had a similar effect as suramin. These treatments did not affect the α₂-adrenoceptor-mediated inhibition of cAMP production. This indicates that cells may be primed or their signaling pathways redirected towards Ca²⁺ mobilisation by `autocrine' release of nucleotides.     

Activation of type I collagen genes in cultured scleroderma fibroblasts

Fibroblasts cultured from affected skin areas of five patients with cutaneous scleroderma were found to produce increased amounts of collagen when compared with nonaffected control cells. Total RNA was isolated from the cultures and analyzed for its level of pro alpha 1 (I)collagen mRNA by hybridization of RNA blots with a cloned cDNA probe. The levels of pro alpha 1 (I)collagen mRNAs relative to total RNA were two- to sixfold higher in the samples from affected cells, accounting for the increased synthesis of type I collagen. Cytoplasmic dot hybridizations were performed to measure the cellular content of pro alpha 1 (I)collagen mRNA: up to ninefold increases in the level of this mRNA per cell were found. Upon subculturing, scleroderma fibroblasts were found to reduce gradually the increased synthesis of collagen to the level of nonaffected controls by the tenth passage. The levels of type I collagen mRNAs were also reduced, but more slowly. The results suggest that in scleroderma fibroblasts the genes for type I collagen are activated at procollagen mRNA level or that they are more stable and that the activating factors are lost during prolonged cell culture because cells from affected areas lose their activated state.     

The effects of coffee consumption on lipid peroxidation and plasma total homocysteine concentrations: a clinical trial

Despite extensive research, the cardiovascular effects of coffee consumption in humans remain controversial. Our aim was to investigate the excretion of coffee phenols and the effects of filtered coffee consumption on oxidative stress and plasma homocysteine (tHcy) concentration in humans. The study consisted of a multiple-dose clinical supplementation trial and a single-dose study. In the long-term trial, 43 healthy nonsmoking men optionally consumed daily either no coffee, 3 cups (450 mL), or 6 cups (900 mL) of filtered coffee for 3 weeks, while in the short-term study 35 subjects consumed a single dose of 0, 1 (150 mL), or 2 cups (300 mL) of coffee. Long-term consumption of coffee increased the urinary excretion of caffeic and ferulic acid. The change in the total excretion of phenolic acids in 3 and 6 cups groups represented 3.8 and 2.5% of the amount ingested daily. Plasma tHcy concentrations increased nonsignificantly, but the consumption of coffee had neither short-nor long-term effects on lipid peroxidation or the activity of measured antioxidant enzymes. In conclusion, the consumption of filtered coffee does not have any detectable effects on lipid peroxidation in healthy nonsmoking men. The effect of coffee consumption on tHcy concentrations needs further investigation.     

A duplexed microsphere-based cellular adhesion assay

Interactions of integrin cellular adhesion molecules with matrix proteins play important roles in complex bidirectional signaling pathways. To investigate these interactions, a novel flow-cytometry-based cellular adhesion assay has been developed. Based on the concept of microcarrier cell culture, derivatized polystyrene microspheres (9.6 microm) are used as a substrate for the immobilization of type I collagen to which cells then adhere. Using cytometric detection, the extent of cellular adhesion can be precisely determined by comparison of adhered and nonadhered populations based on the side scatter properties of the microspheres. In combination with immunostaining, the novel format of this assay enables the correlation of adhesive function to other cellular characteristics such as surface expression. In this work, the protein kinase C activator 12-O-tetradecanoylphorbol-13-acetate (TPA) was used to stimulate increased adhesion in Chinese hamster ovary cells stably transfected with the collagen receptor integrin alpha2beta1. Multiple clones of varying expression distributions were analyzed, and correlations of adherent populations versus receptor distributions show a threefold increase in functional cellular adhesion to collagen upon treatment with TPA. Probability binning analysis of duplexed data revealed subtle changes in adhesion versus receptor distribution mediated by TPA which otherwise would not have been detectable.     

Bone Morphogenetic Protein-2 Is a Regulator of Cell Adhesion

Bone morphogenetic proteins (BMPs) are a group of peptide growth factors closely related to transforming growth factors-β. The BMPs are suggested to play an essential role in bone development and they are strong candidate molecules to be used clinically to improve fracture healing. BMPs are also involved in the differentiation of several other tissues during embryogenesis. Here, we show that human recombinant BMP-2 regulates cell–matrix interactions by modifying the expression of integrin-type receptors. The synthesis of α3 integrin was down-regulated by BMP-2 in two osteogenic sarcoma-derived cell lines, Saos-2 and HOS, and also in human fetal chondrocytes. BMP-2 had no effect on the expression of α1, α2, α5, α6, and αV integrins. BMP-2 reduced the expression of α3 integrin subunit at mRNA level. Laminin-5 was shown to be the ligand for α3β1 integrin on Saos cells and BMP-2 decreased the ability of Saos cells to attach to it. These results suggest that BMP-2 has a specific effect on the α3β1 integrin-mediated cell adhesion to laminin-5. Given the fact that BMP-2 is expressed in osteosarcomas, in addition to in bone, this mechanism is putatively important especially in bone development and tumors. We also studied the effect of BMP-2 on a human keratinocyte cell line, HaCaT. In HaCaT cells, the expression of α2 integrin was strongly down-regulated by BMP-2, whereas its effect on the expression of α3 integrin was smaller. We suggest that the effects of BMP-2 may be partially mediated by specifically altered cell adhesion.     

Fish oil and vitamin E supplementation in oxidative stress at rest and after physical exercise

Sen, Chandan K., Mustafa Atalay, Jyrki Ågren,David E. Laaksonen, Sashwati Roy, and Osmo Hänninen. Fishoil and vitamin E supplementation in oxidative stress at rest and afterphysical exercise. J. Appl. Physiol.83(1): 189-195, 1997.Fish oil supplementation and physicalexercise may induce oxidative stress. We tested the effects of 8 wk of-tocopherol (vitamin E) and fish oil (FO) supplementation on resting and exercise-induced oxidative stress. Rats(n = 80) were divided into groupssupplemented with FO, FO and vitamin E (FOVE), soy oil (SO), and SO andvitamin E (SOVE), and for FOVE and SOVE they were dividedinto corresponding exercise groups (FOVE-Ex and SOVE-Ex). Lipidperoxidation [thiobarbituric acid-reacting substances(TBARS)] was 33% higher in FO compared with SO in the liver, butoxidative protein damage (carbonyl levels) remained similar in bothliver and red gastrocnemius muscle (RG). Vitamin E supplementation,compared with FO and SO, markedly decreased liver and RG TBARS, butliver TBARS remained 32% higher in FOVE vs. SOVE. Vitamin E alsomarkedly decreased liver and RG protein carbonyl levels, althoughlevels in FOVE and SOVE were similar. Exercise increased liver and RGTBARS and RG protein carbonyl levels markedly, with similar levels inFOVE-Ex and SOVE-Ex. FO increased lipid peroxidation but not proteinoxidation in a tissue-specific manner. Vitamin E markedly decreasedlipid peroxidation and protein oxidation in both FOVE and SOVE,although liver lipid peroxidation remained higher in FOVE. Despitehigher levels of hepatic lipid peroxidation at rest in FOVE comparedwith SOVE, liver appeared to be relatively less susceptible toexercise-induced oxidative stress in FOVE.

     

Integrin evolution: insights from ascidian and teleost fish genomes.

Integrins are a family of alphabeta heterodimeric receptors essential to cell adhesion in all metazoans. In humans, the family consists of 18 alpha and 8 beta subunits that combine to form 24 dimers. Here, we present phylogenetic reconstructions for the alpha and beta integrin subunits based on sequences from 24 invertebrate and vertebrate species, including the fully sequenced genomes of the ascidian Ciona intestinalis (a urochordate) and the pufferfish Takifugu rubripes (a teleost). Both genomes contain integrin alpha subunits that have the inserted alphaI domain. As for the one alphaI domain containing integrin alpha subunit discovered earlier from the ascidian Halocynthia roretzi, the Ciona alphaI domains are missing the distinctive characteristics of mammalian collagen receptors and segregate from all vertebrate alphaI domain integrins in a phylogenetic tree, forming a new subgroup of alpha subunits with alphaI domains. Each of the pufferfish alphaI domain sequences does have characteristics of the collagen receptor alphaI domains, but no leukocyte-specific alphaI domains were found in pufferfish. Comparative protein modeling suggests that several of these fish alphaI domains are structurally compatible with binding to a GFOGER sequence in a collagen triple helix.