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81.
Jani Heino Jari Ilmonen Juho Kotanen Heikki Mykr Lauri Paasivirta Janne Soininen Risto Virtanen 《Ecological Indicators》2009,9(6):1179-1187
Extensive surveys of biodiversity in protected and managed areas have not been conducted for a majority of taxonomic groups and ecosystem types, which makes it difficult to assess how large a portion of biodiversity is at least potentially under protection. The situation is the same in boreal regions, and only preliminary analyses of the biodiversity patterns of less well-known organism groups, including many freshwater taxa, within the protected area network have been conducted. We studied patterns of species richness and community composition of algae, macrophytes (bryophytes and vascular plants), and macroinvertebrates of headwater streams draining protected areas and managed forests in a boreal drainage basin in Finland. We found no significant differences in the species richness and community composition of these organism groups between the protected and managed streams. Gamma- and beta-diversity varied strongly among the protected and managed stream groups, yet this variation was contingent on the organism group and the beta-diversity measure used. In general, there was much species turnover within both protected and managed stream groups, masking any between-group differences. However, we found a number of redlisted and rare species in our surveys. Of these species, several macrophyte species occurred more frequently in the protected streams. By contrast, rare species of algae and macrophytes did not generally show such inclinations to the protected streams. We found no strong congruence in species richness or community dissimilarity between algae, macrophytes, and macroinvertebrates, suggesting that the main anthropogenic gradient in terms of forestry is not strong enough to modify stream environmental conditions and thereby shape biodiversity in the focal drainage basin. This finding also suggests that surveys of aquatic biodiversity across protected and managed landscapes should not rely too heavily on the surrogate taxon approach, but instead should consider patterns shown by multiple taxonomic groups that represent biologically and ecologically disparate organisms. Our results indeed suggest that the levels of alpha-, beta-, and gamma-diversity show differing among-taxon responses to forest management and naturalness of headwater streams. 相似文献
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Niko M. Jukarainen Samuli-Petrus Korhonen Mikko P. Laakso Minna A. Korolainen Matthias Niemitz Pasi P. Soininen Kari Tuppurainen Jouko Vepsäläinen Tuula Pirttilä Reino Laatikainen 《Metabolomics : Official journal of the Metabolomic Society》2008,4(2):150-160
A protocol for quantitative 1H NMR analysis of human cerebrospinal fluid (hCSF) was built up and assessed as based on Constrained Total-Line-Shape (CTLS)
fitting. In this method, linear constraints were applied to spectral structures. The 1H NMR spectra of 45 human CSF samples were measured and quantified using the CTLS method. The quantification strategies based
on total-line-shape fitting are discussed. The metabolic model for CTLS includes 31 metabolites covering 85% of the total
spectral intensity, excluding the protein contribution. Prior to data analysis, the data was divided into patients with no
Alzheimer’s disease (AD), but with a normal AD marker profile (the peptide β-amyloid42 and tau protein) present in CSF, and into controls that do not have an AD marker profile in CSF. Unexpectedly large variations
in metabolite concentrations within the two patient groups were detected, but an analysis of variance revealed a significant
(P = 0.027) difference only in the concentration of creatinine which was higher in patients that had a normal AD marker profile.
Multivariate classification tools such as self-organizing maps (SOM) failed in separation of the two classes. 相似文献
84.
Jianjun Wang Janne Soininen Emilio O. Casamayor Feiyan Pan Xiangming Tang Xiangdong Yang Yunlin Zhang Qinglong Wu Jizhong Zhou Ji Shen 《Ecography》2017,40(3):393-402
Although elevational gradients in microbial biodiversity have attracted increasing attention recently, the generality in the patterns and underlying mechanisms are still poorly resolved. Further, previous studies focused mostly on species richness, while left understudied evenness, another important aspect of biodiversity. Here, we studied the elevational patterns in species richness and evenness of stream biofilm bacteria and diatoms in six mountains in Asia and Europe. We also reviewed published results for elevational richness patterns for soil and stream microbes in a literature analysis. Our results revealed that even within the same ecosystem type (that is, stream) or geographical region, bacteria and diatoms showed contrasting patterns in diversity. Stream microbes, including present stream data, tend to show significantly increasing or decreasing elevational patterns in richness, contrasting the findings for soil microbes that typically showed nonsignificant or significantly decreasing patterns. In all six mountains for bacteria and in four mountains for diatoms, species richness and evenness were positively correlated. The variation in bacteria and diatom richness and evenness were substantially explained by anthropogenic driven factors, such as total phosphorus (TP). However, diatom richness and evenness were also related to different main drivers as richness was mostly related to pH, while evenness was most explained by TP. Our results highlight the lack of consistent elevational biodiversity patterns of microbes and further indicate that the two facets of biodiversity may respond differently to environmental gradients. 相似文献
85.
Qi Li Xue Yang Janne Soininen Cheng-Jin Chu Jie-Qi Zhang Kai-Liang Yu Gang Wang 《Journal of Plant Ecology》2011,4(4):249
Aims Spatial processes and environmental control are the two distinct, yet not mutually exclusive forces of community structuring, but the relative importance of these factors is controversial due to the species-specific dispersal ability, sensitivity towards environmental variables, organism's abundance and the effect of spatial scale. In the present paper, we explored spatial versus environmental control in shaping community composition (i.e. β-diversity) and species turnover (i.e. change of β-diversity) at an alpine meadow along a slope aspect gradient on the Qinghai–Tibetan Plateau at different spatial scales of sampling (quadrats and plots), by taking account of seed dispersal mode and abundance.Methods We examined the relative importance of spatial processes and environmental factors using all species and four additional subsets of selected species. Moreover, we attempted to explore the effect of scale (quadrat refers to scale of ~0.3 m and plot of ~8 m) on their counter balance. The data were analyzed both by variation partitioning and multiple regressions on distance matrices. The spatial structure was modelled using Moran's eigenvector maps (MEM).Important findings Both spatial processes and environmental factors were important determinants of the community composition and species turnover. The community composition in the alpine meadow was controlled by spatially structured environment (17.6%), space independent of environment (18.0%) and a negligible effect of environment independent of space (4.4%) at the scale of quadrats. These three components contributed 21.8, 9.9 and 13.9%, respectively, at the scale of plots. The balance between the forces at different spatial scales drove community structures along the slope aspect gradient. The importance of environmental factors on β-diversity at alpine meadow increased with scale while that of spatial processes decreased or kept steady, depending on dispersal mode and abundance of species comprising the subset. But the 'pure' effect of spatial processes on species turnover increased with scale while that of environmental factors decreased. This discrepancy highlights that β-diversity and species turnover were determined jointly by spatial processes and environmental factors. We also found that the relative roles of these processes vary with spatial scale. These results underline the importance of considering species-specific dispersal ability and abundance of species comprising the communities and the appropriate spatial scale in understanding the mechanisms of community assembly. 相似文献
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88.
In a double-blind, placebo-controlled study, the central nervous system effects of an ACTH4-9 analog, Org2766 (40 mg/day), in Alzheimer's disease were assessed by measuring cerebrospinal fluid parameters during 6 months' treatment. Somatostatin-like immunoreactivity and cholinesterase activity, which are known to be reduced in cerebrospinal fluid of Alzheimer patients compared with controls, did not change during treatment. As a marker of noradrenergic and dopaminergic systems, we measured dopamine-beta-hydroxylase and homovanillic acid, but both levels were static. These results suggest that Org2766 did not interact with the transmitter systems, which are thought to be disturbed in Alzheimer's disease. 相似文献
89.
Mitochondrial DNA polymorphisms as risk factors for Parkinson’s disease and Parkinson’s disease dementia 总被引:8,自引:0,他引:8
Autere J Moilanen JS Finnilä S Soininen H Mannermaa A Hartikainen P Hallikainen M Majamaa K 《Human genetics》2004,115(1):29-35
The activity of complex I of the mitochondrial respiratory chain has been found to be decreased in patients with Parkinsons disease (PD), but no mutations have been identified in genes encoding complex I subunits. Recent studies have suggested that polymorphisms in mitochondrial DNA (mtDNA)-encoded complex I genes (MTND) modify susceptibility to PD. We hypothesize that the risk of PD is conveyed by the total number of nonsynonymous substitutions in the MTND genes in various mtDNA lineages rather than by single mutations. To test this possibility, we determined the number of nonsynonymous substitutions of the seven MTND genes from 183 Finns. The differences in the total number of nonsynonymous substitutions and the nonsynonymous to synonymous substitution rate ratio (Ka/Ks) of MTND genes between the European mtDNA haplogroup clusters (HV, JT, KU, IWX) were analysed by using a statistical approach. Patients with PD (n=238) underwent clinical examination together with mtDNA haplogroup analysis and the clinical features between patient groups defined by the number of nonsynonymous substitutions were compared. Our analysis revealed that the haplogroup clusters HV and KU had a lower average number of amino acid replacements and a lower Ka/Ks ratio in the MTND genes than clusters JT and IWX. Supercluster JTIWX with the highest number of amino acid replacements was more frequent among PD patients and even more frequent among patients with PD who developed dementia. Our results suggest that a relative excess of nonsynonymous mutations in MTND genes in supercluster JTWIX is associated with an increased risk of PD and the disease progression to dementia. 相似文献
90.
Koistinen KM Soininen P Venäläinen TA Häyrinen J Laatikainen R Peräkylä M Tervahauta AI Kärenlampi SO 《Phytochemistry》2005,66(21):2524-2533
PR-10c is a unique member of PR-10 proteins in birch, since it is the only one known to be post-translationally modified by glutathione and is not constitutively expressed in pollen. Both reduced and S-glutathiolated forms of PR-10c show low ribonuclease activity. However, the major function of the protein is apparently not yet resolved. Our protein-ligand interaction studies with saturation transfer difference (STD) NMR revealed that PR-10c interacts with several biologically important molecules, including cytokinin, flavonoid glycosides, sterols and emodin. Competition study with deoxycholate and kinetin revealed no statistically significant binding interference, indicating that these ligands have different binding sites in PR-10c. Ligand docking studies with a molecular model of PR-10c support the STD NMR results of ligand binding and binding epitopes, suggesting that there are three potential binding sites in PR-10c: two in the hydrophobic cavity and one in the glycine-rich loop. Our docking calculations suggested that only kinetin interacts with the glycine-rich loop, the binding occurring through its adenine moiety. Clear ligand specificity could be observed in the binding of nucleotide derivatives. S-glutathiolation of PR-10c did not affect kinetin binding. The present results suggest that birch PR-10c is a multifunctional protein, which has diverse roles in plant stress responses. 相似文献