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Knowledge about elevational β diversity patterns and processes is limited for microorganisms, especially in sensitive aquatic ecosystems at high latitudes. Our aim is to investigate elevational β diversity patterns and underlying assembly processes for three biofilm microbial groups in subarctic freshwater ponds.We sampled 89 ponds covering an elevational gradient from 10 to 1038 m above sea level in subarctic Finland and Norway. The microbial groups studied included benthic diatoms, cyanobacteria, and bacteria (i.e., bacteria other than cyanobacteria). We expected to find elevational distance decay in community similarity, driven primarily by variation in the local environment. We further tested whether the level of β diversity decreased towards higher elevations, and whether the relative influence of deterministic and stochastic processes on community assembly changed along the elevational gradient, with increasing effect of deterministic processes at higher elevations under more extreme environmental conditions. As statistical methods, we used generalised dissimilarity modelling, Mantel tests, and a null model with Raup–Crick dissimilarities.For all microbial groups, community dissimilarities increased with increasing environmental or elevational distances. The pure effects of environment were significant for all groups, and pH was the most important variable affecting community dissimilarities. Mean community dissimilarities generally decreased with elevation for all microbial groups. The communities were influenced by both deterministic and stochastic processes, the former of which was stronger towards higher elevations. The influence of deterministic processes was strongest for bacteria. Generally, the communities under deterministic control were more similar to each other than expected by chance.Elevational β diversity patterns of subarctic pond microorganisms primarily reflected environmental effects, showing decreasing β diversity towards high elevations owing to stronger environmental filtering. The relative effects of deterministic or stochastic assembly processes varied among microbial groups, highlighting the need for including multiple groups when studying biodiversity patterns and underlying ecological processes. [ABSTRACT FROM AUTHOR]

Aim: To discover how biological traits, ecological preferences and taxonomic relatedness are associated with occupancy and abundance of diatom species across lakes and streams. Location: Finland. Taxon: Diatoms. Methods: We studied 288 diatom species from 492 stream sites and 230 diatom species from 290 lake sites. For each species, we calculated logit‐transformed regional occupancy and log‐transformed mean local abundance, and further determined biological traits, ecological preferences and taxonomic levels for each species. Boosted regression tree (BRT) analysis was used to reveal the linear and nonlinear associations of biological, ecological and taxonomic predictors with occupancy or abundance of lake and stream diatoms. Results: There were strong and positive interspecific occupancy–abundance relationships across both lakes and streams. The BRT models explained more deviances in variation in occupancy and abundance and their relationship for lakes than streams. Biological traits, especially cell size, but also life‐form and guild, were the strongest predictors of diatom occupancy and abundance in lakes and streams when controlling for ecological preferences and taxonomic relatedness. Main conclusions: In general, biological traits were the strongest predictors of occupancy and abundance in both freshwater systems. Species with similar biological traits thus tended to show similar occupancies and abundances. As indicated by lower explained deviances, occupancy and abundance in streams seemed to be more complexly structured than in lakes, suggesting that these two freshwater system types differ in the formation of biodiversity patterns. This difference may be related to the differences in hydrological connectedness between lakes and streams. Understanding how variations in species' occupancy and abundance are formed across various waterbodies is important for meaningful biodiversity conservation. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- We investigated the relationship of the metabolic syndrome and its single components, defined by four different criteria, with peripheral vascular disease (PVD) in a prospective population-based study. RESEARCH DESIGN AND METHODS-- The metabolic syndrome was defined according to the World Health Organization (WHO), the National Cholesterol Education Program (NCEP), the International Diabetes Federation (IDF), and the American Heart Association (updated NCEP) criteria. We investigated the relationship of the metabolic syndrome defined by the aforementioned four criteria with PVD (revacularization and amputation) by Cox regression analyses in a Finnish population of 1,212 subjects, aged 65-74 years, with and without diabetes during a 14-year follow-up. RESULTS -- The metabolic syndrome defined by the WHO, NCEP, and updated NCEP criteria was associated with a statistically significant risk for incident PVD (n = 57) with adjustment for all confounding variables except for prevalent diabetes (hazard ratios [HRs] from 1.91 to 2.62). After adjustment for prevalent diabetes or after the exclusion of subjects with prevalent diabetes, there was no association between the metabolic syndrome by any criteria and incident PVD. Of the single components of the metabolic syndrome, elevated fasting glucose by the WHO and NCEP criteria (HR 2.35) and microalbuminuria by the WHO definition (2.56) predicted PVD in multivariable models (prevalent diabetes included). CONCLUSIONS -- The metabolic syndrome defined by the WHO, NCEP, and updated NCEP criteria predicted incident end-stage PVD in elderly Finns but only when not adjusted for diabetes status. Two of the single components of the metabolic syndrome, elevated fasting plasma glucose and microalbuminuria, predicted PVD. We conclude that the metabolic syndrome predicts PVD but not above and beyond the risk associated with diabetes and microalbuminuria. [ABSTRACT FROM AUTHOR]

The spatial structure and underlying assembly mechanisms of bacterial communities have been studied widely across aquatic systems, focusing primarily on isolated sites, such as different lakes, ponds and streams. Here, our main aim was to determine the underlying mechanisms for bacterial biofilm assembly within a large, highly connected lake system in Northern Finland using associative methods based on taxonomic and phylogenetic alpha- and beta-diversity and a large number of abiotic and biotic variables. Furthermore, null model approaches were used to quantify the relative importance of different community assembly processes. We found that spatial variation in bacterial communities within the lake was structured by different assembly processes, including stochasticity, species sorting and potentially even dispersal limitation. Species sorting by abiotic environmental conditions explained more of the taxonomic and particularly phylogenetic turnover in community composition compared with that by biotic variables. Finally, we observed clear differences in alpha diversity (species richness and phylogenetic diversity), which were to a stronger extent determined by abiotic compared with biotic factors, but also by dispersal effects. In summary, our study shows that the biodiversity of bacterial biofilm communities within a lake ecosystem is driven by within-habitat gradients in abiotic conditions and by stochastic and deterministic dispersal processes.

Background: The Finnish Diabetes Risk Score (FINDRISC) is a well established method to evaluate the risk of type 2 diabetes. However, it is unknown whether biochemical markers or confirmed type 2 diabetes risk genes improve the risk evaluation beyond the FINDRISC., Objective: We investigated the role of biochemical markers and type 2 diabetes risk loci in the identification of previously undiagnosed diabetic subjects beyond the FINDRISC in a cross-sectional study., Research Design and Methods: A random sample of 7232 Finnish men aged 45-74 yr (including 518 men with new type 2 diabetes) participated in the study. Insulin sensitivity and insulin secretion were evaluated by oral glucose tolerance test-derived indices. Total triglycerides, high-density lipoprotein cholesterol, adiponectin, and alanine transaminase were measured. Nineteen type 2 diabetes risk single-nucleotide polymorphisms were genotyped., Results: FINDRISC was the best single indicator of prevalent undiagnosed diabetes among all variables tested and strongly associated with insulin resistance. It was also more strongly associated with insulin secretion compared with the type 2 risk alleles. The receiver operating characteristics area under the curve based on logistic regression models for the identification of previously undiagnosed type 2 diabetic subjects with the FINDRISC alone was 0.727, and 0.772 after adding total triglycerides, high-density lipoprotein cholesterol, adiponectin, and alanine transaminase in the model. Adding type 2 risk alleles did not further improve the model (0.772)., Conclusions: Biochemical markers, but not genetic markers, improve the identification of previously undiagnosed type 2 diabetes beyond the FINDRISC alone.

Objective: We investigated whether the metabolic syndrome (MetS) and its components defined by four different criteria including subjects with prevalent diabetes in their definitions were associated with congestive heart failure (CHF) independent of interim myocardial infarction (MI) and prevalent diabetes during a 20-year follow-up in an elderly population-based study., Methods and Results: The MetS was defined according to the World Health Organization (WHO), the National Cholesterol Education Program (NCEP), the International Diabetes Federation (IDF), and the American Heart Association and the National Heart, Lung, and Blood Institute (AHA) criteria. The association of the MetS with incident CHF (303 cases) was investigated with Cox regression analyses in a 20-year follow-up study of 1032 Finns, aged 65-74 years at baseline. Among all subjects the MetS by all four criteria was significantly associated with a 1.45-1.74-fold risk for incident CHF after the adjustment for confounding factors. When subjects with interim MI during the follow-up and with prevalent diabetes were excluded, the MetS was significantly associated with a 1.37-1.87-fold risk for incident CHF after the adjustment for confounding factors. Of the single components of the MetS, the following were associated with incident CHF: impaired fasting glucose (IFG) [fasting plasma glucose (FPG)> or = 6.1 mmol/l, Hazards ratio (HR) 1.46 or FPG > or = 5.6 mmol/l, HR 1.62)]; raised blood pressure (BP) [(BP > or = 140/90 mmHg or antihypertensive medications, HR 1.89); central obesity (waist circumference > or = 94 cm in men or > or = 80 cm in women, HR 1.49); (waist circumference > or = 102 cm in men or > or = 88 cm in women, HR 1.48); obesity (body mass index > or = 30 kg/m(2), HR 1.79); and low high-density lipoprotein cholesterol (<1.03 mmol/l in men or <1.29 mmol/l in women, HR 1.55)., Conclusions: The MetS defined by four different criteria predicted CHF independent of interim MI and prevalent diabetes in elderly Finns, but not above and beyond the risk associated with one component of the MetS, hypertension., (Copyright 2009 Elsevier Ireland Ltd. All rights reserved.)