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排序方式: 共有279条查询结果,搜索用时 15 毫秒
1.
Jyri Seppla Matti Melanen Ilmo Menp Sirkka Koskela Jyrki Tenhunen Marja‐Riitta Hiltunen 《Journal of Industrial Ecology》2005,9(4):117-130
The concept of eco-efficiency is commonly referred to as a business link to sustainable development. In this article, ecoefficiency is examined at a regional level as an approach to promoting the competitiveness of economic activities in the Finnish Kymenlaakso region and mitigating their harmful impacts on the environment. The aim is to develop appropriate indicators for monitoring changes in the eco-efficiency of the region. A starting point is to produce indicators for the environmental and economic dimensions of regional development and use them for measuring regional eco-efficiency. The environmental impact indicators are based on a life-cycle assessment method, producing different types of environmental impact indicators: pressure indicators (e.g., emissions of CO2 ), impact category indicators (e.g., CO2 equivalents in the case of climate change), and a total impact indicator (aggregating different impact category indicator results into a single value). Environmental impact indicators based on direct material input, total material input, and total material requirement of the Kymenlaakso region are also assessed. The economic indicators used are the gross domestic product, the value added, and the output of the main economic sectors of Kymenlaakso. In the eco-efficiency assessment, the economic and environmental impact indicators are monitored in the same graph. In a few cases eco-efficiency ratios can also be calculated (the economic indicators are divided by the environmental indicators). Output (= value added + intermediate consumption) is used as an economic indicator related to the environmental impact indicators, which also cover the upstream processes of the region's activities. In the article, we also discuss the strengths and weaknesses of using the different environmental impact indicators. 相似文献
2.
J.Kalervo Hiltunen E.Jack Davis 《Biochimica et Biophysica Acta (BBA)/General Subjects》1981,678(1):115-121
The mechanism of depletion of tricarboxylic acid cycle intermediates by isolated rat heart mitochondria was studied using hydroxymalonate (an inhibitor of malic enzymes) and mercaptopicolinate (an inhibitor of phosphoenolpyruvate carboxykinase) as tools. Hydroxymalonate inhibited the respiration rate of isolated mitochondria in state 3 by 40% when 2 mM malate was the only external substrate, but no inhibition was found with 2 mM malate plus 0.5 mM pyruvate as substrates. In the prescence od bicarbonate, arsenite and ATP, propionate was converted to pyruvate and malate at the rates of 14.0 ± 2.9 and 2.8 ± 1.8 nmol/mg protein in 5 min, respectively. Under these conditions, 0.1 mM mercaptopicolinate did not affect this conversion, but 2 mM hydroxymalonate inhibited pyruvate formation completely and resulted in an accumulation of malate up to 13.2 ± 2.9 nmol/mg protein. No accumulation of phosphoenolpyruvate was found under any condition tested. It is concluded that malic enzymes but not phosphoenolpyruvate carboxykinase, are involved in conversion of propionate to pyruvate in isolated rat heart mitochondria. 相似文献
3.
Epimerization of 3-hydroxyacyl-CoA esters in rat liver. Involvement of two 2-enoyl-CoA hydratases 总被引:1,自引:0,他引:1
Interconversion of D- and L-isomers of 3-hydroxy-decanoyl-CoA was catalyzed by rat liver homogenate. Cation exchange chromatography followed by ammonium sulfate precipitation and PBE-94 chromatofocusing column was used to separate the peroxisomal bifunctional protein, the classic 2-enoyl-CoA hydratase (crotonase), and a novel 2-enoyl-CoA hydratase. Epimerization activity was lost during the last purification step. None of the above proteins was capable of catalyzing the epimerization by itself, but reconstitution was achieved by recombining crotonase and the novel 2-enoyl-CoA hydratase. Since hydration by the latter enzyme follows a different stereochemical course from that with crotonase, these two hydratases are distinguished as 2-enoyl-CoA hydratase 1 (crotonase) and 2-enoyl-CoA hydratase 2 (the novel hydratase). The data strongly suggested that epimerization in the rat liver proceeds via dehydration-hydration catalyzed by the two different hydratases. The intermediate of this two step mechanism appears to be trans-2-enoyl-CoA. 相似文献
4.
Anu Lipsanen Stefanie Flunkert Kristina Kuptsova Mikko Hiltunen Manfred Windisch Birgit Hutter-Paier Jukka Jolkkonen 《PloS one》2013,8(3)
Experimental studies have identified a complex link between neurodegeneration, β-amyloid (Aβ) and calcium homeostasis. Here we asked whether early phase β-amyloid pathology in transgenic hAPPSL mice exaggerates the ischemic lesion and remote secondary pathology in the thalamus, and whether a non-selective calcium channel blocker reduces these pathologies. Transgenic hAPPSL (n = 33) and non-transgenic (n = 30) male mice (4–5 months) were subjected to unilateral cortical photothrombosis and treated with the non-selective calcium channel blocker bepridil (50 mg/kg, p.o., once a day) or vehicle for 28 days, starting administration 2 days after the operation. Animals were then perfused for histological analysis of infarct size, Aβ and calcium accumulation in the thalamus. Cortical photothrombosis resulted in a small infarct, which was associated with atypical Aβ and calcium accumulation in the ipsilateral thalamus. Transgenic mice had significantly smaller infarct volumes than non-transgenic littermates (P<0.05) and ischemia-induced rodent Aβ accumulation in the thalamus was lower in transgenic mice compared to non-transgenic mice (P<0.01). Bepridil decreased calcium load in the thalamus (P<0.01). The present data suggest less pronounced primary and secondary pathology in hAPPSL transgenic mice after ischemic cortical injury. Bepridil particularly decreased calcium pathology in the thalamus following ischemia. 相似文献
5.
DANIEL TRAN TAKASHI KADONO MARIA LIA MOLAS RAFIK ERRAKHI JOËL BRIAND BERNADETTE BILIGUI TOMONORI KAWANO FRANÇOIS BOUTEAU 《Plant, cell & environment》2013,36(3):569-578
Ozone (O3) is an air pollutant with an impact increasingly important in our industrialized world. It affects human health and productivity in various crops. We provide the evidences that treatment of Arabidopsis thaliana with O3 results in ascorbate‐derived oxalic acid production. Using cultured cells of A. thaliana as a model, here we further showed that oxalic acid induces activation of anion channels that trigger depolarization of the cell, increase in cytosolic Ca2+ concentration, generation of reactive oxygen species and cell death. We confirmed that O3 reacts with ascorbate in the culture, thus resulting in production of oxalic acid and this could be part of the O3‐induced signalling pathways that trigger programmed cell death. 相似文献
6.
Sascha M. Kirchner Lea Hiltunen Thomas F. D?ring Elina Virtanen Jukka P. Palohuhta Jari P. T. Valkonen 《PloS one》2013,8(8)
Background
The species diversity of aphids and seasonal timing of their flight activity can have significant impacts on crop production, as aphid species differ in their ability to transmit plant viruses and flight timing affects virus epidemiology. The aim of the study was to characterise the species composition and phenology of aphid fauna in Finland in one of the northernmost intensive crop production areas of the world (latitude 64°).Methodology/Principal Findings
Flight activity was monitored in four growing seasons (2007–010) using yellow pan traps (YPTs) placed in 4–8 seed potato fields and a Rothamsted suction trap. A total of 58,528 winged aphids were obtained, identified to 83 taxa based on morphology, and 34 species were additionally characterised by DNA barcoding. Seasonal flight activity patterns analysed based on YPT catch fell into three main phenology clusters. Monoecious taxa showed early or middle-season flight activity and belonged to species living on shrubs/trees or herbaceous plants, respectively. Heteroecious taxa occurred over the entire potato growing season (ca. 90 days). Abundance of aphids followed a clear 3-year cycle based on suction trap data covering a decade. Rhopalosiphum padi occurring at the end of the potato growing season was the most abundant species. The flight activity of Aphis fabae, the main vector of Potato virus Y in the region, and Aphis gossypii peaked in the beginning of potato growing season.Conclusions/Significance
Detailed information was obtained on phenology of a large number aphid species, of which many are agriculturally important pests acting as vectors of plant viruses. Aphis gossypii is known as a pest in greenhouses, but our study shows that it occurs also in the field, even far in the north. The novel information on aphid phenology and ecology has wide implications for prospective pest management, particularly in light of climate change. 相似文献7.
Lyzel S. Elias-Sonnenschein Seppo Helisalmi Teemu Natunen Anette Hall Teemu Paajanen Sanna-Kaisa Herukka Marjo Laitinen Anne M. Remes Anne M. Koivisto Kari M. Mattila Terho Lehtim?ki Frans R. J. Verhey Pieter Jelle Visser Hilkka Soininen Mikko Hiltunen 《PloS one》2013,8(4)
Objectives
To understand the relation between risk genes for Alzheimer’s disease (AD) and their influence on biomarkers for AD, we examined the association of AD in the Finnish cohort with single nucleotide polymorphisms (SNPs) from top AlzGene loci, genome-wide association studies (GWAS), and candidate gene studies; and tested the correlation between these SNPs and AD markers Aβ1–42, total tau (t-tau), and phosphorylated tau (p-tau) in cerebrospinal fluid (CSF).Methods
We tested 25 SNPs for genetic association with clinical AD in our cohort comprised of 890 AD patients and 701-age matched healthy controls using logistic regression. For the correlational study with biomarkers, we tested 36 SNPs in a subset of 222 AD patients with available CSF using mixed models. Statistical analyses were adjusted for age, gender and APOE status. False discovery rate for multiple testing was applied. All participants were from academic hospital and research institutions in Finland.Results
APOE-ε4, CLU rs11136000, and MS4A4A rs2304933 correlated with significantly decreased Aβ1–42 (corrected p<0.05). At an uncorrected p<0.05, PPP3R1 rs1868402 and MAPT rs2435211 were related with increased t-tau; while SORL1 rs73595277 and MAPT rs16940758, with increased p-tau. Only TOMM40 rs2075650 showed association with clinical AD after adjusting for APOE-ε4 (p = 0.007), but not after multiple test correction (p>0.05).Conclusions
We provide evidence that APOE-ε4, CLU and MS4A4A, which have been identified in GWAS to be associated with AD, also significantly reduced CSF Aβ1–42 in AD. None of the other AlzGene and GWAS loci showed significant effects on CSF tau. The effects of other SNPs on CSF biomarkers and clinical AD diagnosis did not reach statistical significance. Our findings suggest that APOE-ε4, CLU and MS4A4A influence both AD risk and CSF Aβ1–42. 相似文献8.
9.
10.
Riikka Jokinen Taina Lahtinen Paula Marttinen Maarit My?h?nen Pilvi Ruotsalainen Nicolas Yeung Antonina Shvetsova Alexander J. Kastaniotis J. Kalervo Hiltunen Tiina ?hman Tuula A. Nyman Hartmut Weiler Brendan J. Battersby 《Genetics》2015,200(1):221-235
Mammalian mitochondrial DNA (mtDNA) is a high-copy maternally inherited genome essential for aerobic energy metabolism. Mutations in mtDNA can lead to heteroplasmy, the co-occurence of two different mtDNA variants in the same cell, which can segregate in a tissue-specific manner affecting the onset and severity of mitochondrial dysfunction. To investigate mechanisms regulating mtDNA segregation we use a heteroplasmic mouse model with two polymorphic neutral mtDNA haplotypes (NZB and BALB) that displays tissue-specific and age-dependent selection for mtDNA haplotypes. In the hematopoietic compartment there is selection for the BALB mtDNA haplotype, a phenotype that can be modified by allelic variants of Gimap3. Gimap3 is a tail-anchored member of the GTPase of the immunity-associated protein (Gimap) family of protein scaffolds important for leukocyte development and survival. Here we show how the expression of two murine Gimap3 alleles from Mus musculus domesticus and M. m. castaneus differentially affect mtDNA segregation. The castaneus allele has incorporated a uORF (upstream open reading frame) in-frame with the Gimap3 mRNA that impairs translation and imparts a negative effect on the steady-state protein abundance. We found that quantitative changes in the expression of Gimap3 and the paralogue Gimap5, which encodes a lysosomal protein, affect mtDNA segregation in the mouse hematopoietic tissues. We also show that Gimap3 localizes to the endoplasmic reticulum and not mitochondria as previously reported. Collectively these data show that the abundance of protein scaffolds on the endoplasmic reticulum and lysosomes are important to the segregation of the mitochondrial genome in the mouse hematopoietic compartment. 相似文献