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91.
92.
Arachidonic acid (AA) can be metabolized to various metabolites, which can act as mediators of cellular processes. The objective of this work was to identify whether AA, prostaglandin (PG) B1 and E2, and 15- and 20-hydroxyeicosatetraenoic acids (15- and 20-HETE) are metabolized via glucuronidation. Assays with human recombinant UDP-glucuronosyltransferase 1A (UGT1A) isoforms revealed that AA and 15-HETE were glucuronidated by UGT1A1, 1A3, 1A4, 1A9, and 1A10, whereas 20-HETE was glucuronidated by UGT1A1 and 1A4 and PGB1 was glucuronidated by UGT1A1, 1A9, and 1A10. All substrates were glucuronidated by recombinant UGT2B7, with AA and 20-HETE being the best substrates. Kinetic analysis of UGT1A1 and 1A9 with AA resulted in Km values of 37.9 and 45.8 microM, respectively. PGB1 was glucuronidated by UGT1A1 with a Km of 26.3 microM. The Km values for all substrates with UGT2B7 were significantly higher than with the UGT1A isoforms. Liquid chromatography-mass spectrometry of glucuronides biosynthesized from PGB1 and 15-HETE showed that hydroxyl groups were the major target of glucuronidation. This work demonstrates a novel metabolic pathway for HETEs and PGs and the role of UGT1A isoforms in this process. These results indicate that glucuronidation may play a significant role in modulation of the availability of these fatty acid derivatives for cellular processes.  相似文献   
93.
doi:10.1111/j.1741‐2358.2009.00328.x
Number of teeth and selected cardiovascular risk factors among elderly people Objective: To produce evidence on an association between the number of teeth and selected cardiovascular risk factors among an elderly population. Materials and methods: The study population comprised of 523 community‐living elderly people who participated in the population‐based Kuopio 75+ study. The data for each subject were collected using a structured clinical health examination, an interview and laboratory tests. Linear regression models were used to estimate adjusted mean values and confidence limits. Results: Edentulous persons and persons with a small number of teeth had lower serum HDL cholesterol and higher triglyceride, leucocyte and blood glucose levels and a higher body mass index (BMI) compared with subjects to a large number of teeth. Conclusion: The study showed that, in the Finnish home‐dwelling population aged 75 years or older, those with a large number of teeth were less likely to have cardiovascular risk factors such as a low serum HDL cholesterol level, a high triglyceride level and a high BMI than did subjects with a small number of teeth or who were edentulous.  相似文献   
94.
Global climate change is a major threat to biodiversity, posing increasing pressures on species to adapt in situ or shift their ranges. A protected area network is one of the main instruments to alleviate the negative impacts of climate change. Importantly, protected area networks might be expected to enhance the resilience of regional populations of species of conservation concern, resulting in slower species loss in landscapes with a significant amount of protected habitat compared to unprotected landscapes. Based on national bird atlases compiled in 1974–1989 and 2006–2010, this study examines the recent range shifts in 90 forest, mire, marshland, and Arctic mountain heath bird species of conservation concern in Finland, as well as the changes in their species richness in protected versus unprotected areas. The trends emerging from the atlas data comparisons were also related to the earlier study dealing with predictions of distributional changes for these species for the time slice of 2051–2080, developed using bioclimatic envelope models (BEMs). Our results suggest that the observed changes in bird distributions are in the same direction as the BEM‐based predictions, resulting in a decrease in species richness of mire and Arctic mountain heath species and an increase in marshland species. The patterns of changes in species richness between the two time slices are in general parallel in protected and unprotected areas. However, importantly, protected areas maintained a higher level of species richness than unprotected areas. This finding provides support for the significance and resilience provision of protected area networks in preserving species of conservation concern under climate change.  相似文献   
95.
Species ranges are expected to move polewards following the changing climate, which poses novel challenges to the protected area network, particularly at northern latitudes. Here we study how well protected areas are likely to sustain populations of birds of conservation concern under a changing climate in northern Europe, in Finland. We fitted bioclimatic envelope models generated for 100 bird species to climate scenario data for the years 2051–2080 and three alternative emission scenarios in a 10-km grid system to predict changes in the species probability of occurrence. We related the projected changes in the climatic suitability to the amount of protected preferred habitat for the study species in the 10-km grid cells, and based on the cover of four main CORINE Land Cover classes in each conservation area in Finland. The probability of occurrence of all species (except marshland birds) decreased according to all scenarios, the decline being greatest in southern and smallest in northern boreal zones. This decline was slightly greater in unprotected than in protected areas for species of forests, mires and mountain habitats. The climatically suitable areas for the species were predicted to shift northwards, but the potential gain of southern species of conservation concern appears not to compensate for the loss of northern species. Thus, a representative protected area network is needed in all boreal zones. Overall, our results show that species-specific habitat preferences and habitat availability should be taken into account when assessing the efficiency of a protected area network in a changing climate.  相似文献   
96.
Current rates of climate change are unprecedented, and biological responses to these changes have also been rapid at the levels of ecosystems, communities, and species. Most research on climate change effects on biodiversity has concentrated on the terrestrial realm, and considerable changes in terrestrial biodiversity and species’ distributions have already been detected in response to climate change. The studies that have considered organisms in the freshwater realm have also shown that freshwater biodiversity is highly vulnerable to climate change, with extinction rates and extirpations of freshwater species matching or exceeding those suggested for better‐known terrestrial taxa. There is some evidence that freshwater species have exhibited range shifts in response to climate change in the last millennia, centuries, and decades. However, the effects are typically species‐specific, with cold‐water organisms being generally negatively affected and warm‐water organisms positively affected. However, detected range shifts are based on findings from a relatively low number of taxonomic groups, samples from few freshwater ecosystems, and few regions. The lack of a wider knowledge hinders predictions of the responses of much of freshwater biodiversity to climate change and other major anthropogenic stressors. Due to the lack of detailed distributional information for most freshwater taxonomic groups and the absence of distribution‐climate models, future studies should aim at furthering our knowledge about these aspects of the ecology of freshwater organisms. Such information is not only important with regard to the basic ecological issue of predicting the responses of freshwater species to climate variables, but also when assessing the applied issue of the capacity of protected areas to accommodate future changes in the distributions of freshwater species. This is a huge challenge, because most current protected areas have not been delineated based on the requirements of freshwater organisms. Thus, the requirements of freshwater organisms should be taken into account in the future delineation of protected areas and in the estimation of the degree to which protected areas accommodate freshwater biodiversity in the changing climate and associated environmental changes.  相似文献   
97.
This study clarifies the area distribution of Estonian peat soils by three factors: main peat soil groups, peat thickness and peat decomposition degree. A digital soil map (1:10,000) and supplementary database were used for summarizing the distribution of peat soils. From the combined database with 859,701 polygons the soil mapping unit code, formula of soil texture (including peat) and formula of epipedon fabric were compiled using the MapInfo software. Peat soils form altogether 10,038 km2 or 23.5% of the total Estonian soil cover. From the peat soils the fen soils form 59.0%, bog soils 21.7% and transitional bog soils 14.7%. 45% of peat soils are well, 26% moderately and 29% slightly decomposed, by the peat thickness 13% are very shallow, 21% shallow and 66% thick. The general ecological characterization of peat soils and their mutual relationship with plant cover are given for the main peat soil taxa. The dominant natural ecosystems formed on peatlands are: (1) mixed birch, alder, spruce and pine forests on thin (<100 cm) well decomposed eutrophic fen soils, and (2) a sparse pine forests and hummock-ridge-hollow raised bogs wooded sparsely by pine on thick (>100 cm) slightly decomposed oligotrophic bog soils. The accumulation of organic carbon in peatlands soil cover (0–50 cm) totals 269.4±12.7 Tg and in epipedon layer (as superficial part of soil cover; 0–30 cm) 129.9±5.8 Tg. The former is sequestrated into 543.7 Tg of peat, which forms 22.9% of the total Estonian peat resources (2.37 Pg).  相似文献   
98.
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100.
The aim of the study was to evaluate new Mycoplasma pneumoniae IgG, IgA and IgM EIA methods based on the enrichment of P1-protein (ThermoLabsystems, Helsinki, Finland) (L) for the detection of acute infection. This evaluation was performed in two independent routine clinical microbiology laboratories. The first laboratory used samples preselected by IgG and IgM Platelia enzyme immunoassay (P) and the second used samples preseleced by Serion ELISA Classic M. pneumoniae IgG, IgM (V). The L method was also compared to the FDA approved method of ImmunoWell M. pneumoniae IgG and IgM (G). When the agreement of two methods was applied as a serologic criteria for an acute infection, the following ratios of acute to nonacute infection were calculated 32/86 (totally 118) in the first and 20/72 (totally 92) in the second laboratory. In the first laboratory, the corresponding ratios by methods were 35/83 (sensitivity 100%, specificity 96.5%), 31/87 (sensitivity 97%, specificity 100%), and 55/63 (sensitivity 100%, specificity 79%) for the L, P and G methods, respectively. In the second laboratory, the ratios were 21/71 (sensitivity 100%, specificity 99%), 16/76 (sensitivity 83%, specificity 100%), and 53/39 (sensitivity 100, specificity 69%) for the L, V and G methods, respectively. Taking into account that the tested sample material was preselected by the P and V methods, which may have introduced some bias in their favor, the newly developed L method utilizing P1-enriched protein was found reliable for serodiagnosis of acute M. pneumoniae infection. The method G was the least specific in detection of acute infection.  相似文献   
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