Temperament clusters in a normal population: implications for health and disease

Background

The object of this study was to identify temperament patterns in the Finnish population, and to determine the relationship between these profiles and life habits, socioeconomic status, and health.

Methods/Principal Findings

A cluster analysis of the Temperament and Character Inventory subscales was performed on 3,761 individuals from the Northern Finland Birth Cohort 1966 and replicated on 2,097 individuals from the Cardiovascular Risk in Young Finns study. Clusters were formed using the k-means method and their relationship with 115 variables from the areas of life habits, socioeconomic status and health was examined.

Results

Four clusters were identified for both genders. Individuals from Cluster I are characterized by high persistence, low extravagance and disorderliness. They have healthy life habits, and lowest scores in most of the measures for psychiatric disorders. Cluster II individuals are characterized by low harm avoidance and high novelty seeking. They report the best physical capacity and highest level of income, but also high rate of divorce, smoking, and alcohol consumption. Individuals from Cluster III are not characterized by any extreme characteristic. Individuals from Cluster IV are characterized by high levels of harm avoidance, low levels of exploratory excitability and attachment, and score the lowest in most measures of health and well-being.

Conclusions

This study shows that the temperament subscales do not distribute randomly but have an endogenous structure, and that these patterns have strong associations to health, life events, and well-being.     

Allergy symptoms in relation to alder and birch pollen concentrations in Finland

In order to study allergic people responding to daily changes in pollen concentrations, we compared personal diary data on allergic symptoms and the use of allergy medicines to daily pollen counts during the two unequal alder and birch pollen seasons of 2009 and 2010. Almost 90% of the 61 subjects with physician-diagnosed birch pollinosis developed conjunctival, nasal or other symptoms during the peak birch pollination. Most subjects (95%) also reported symptoms during the alder pollination. Despite a delay between the most severe symptoms and the pollen peaks and the increased risk of allergy symptoms between the alder and birch pollen peaks at much lower pollen concentrations, the number of subjects with allergy symptoms correlated with the daily pollen concentrations in both years (r ₀₉ = 0.35, r ₁₀ = 0.36, p < 0.01). The positive correlation was even stronger (r ₀₉ = 0.69, r ₁₀ = 0.74, p < 0.001) in relation to the cumulative sum of daily concentrations. The use of allergy medicines precisely followed the abundance of allergy symptoms in both years (r ₀₉ = 0.96, r ₁₀ = 0.70, p < 0.001). We conclude that there is a fair correlation between the daily allergy symptoms and the particular pollen concentrations, but the risk of developing symptoms at low, moderate and high concentrations is affected by the progression of the pollen season.     

Evolution in response to climate change: In pursuit of the missing evidence

Climate change is imposing intensified and novel selection pressures on organisms by altering abiotic and biotic environmental conditions on Earth, but studies demonstrating genetic adaptation to climate change mediated selection are still scarce. Evidence is accumulating to indicate that both genetic and ecological constrains may often limit populations' abilities to adapt to large scale effects of climate warming. These constraints may predispose many organisms to respond to climate change with range shifts and phenotypic plasticity, rather than through evolutionary adaptation. In general, broad conclusions about the role of evolutionary adaptation in mitigating climate change induced fitness loss in the wild are as yet difficult to make. Editor's suggested further reading in BioEssays: How will fish that evolved at constant sub‐zero temperatures cope with global warming? Notothenioids as a case study Abstract     

Co‐inheritance of sea age at maturity and iteroparity in the Atlantic salmon vgll3 genomic region

Co‐inheritance in life‐history traits may result in unpredictable evolutionary trajectories if not accounted for in life‐history models. Iteroparity (the reproductive strategy of reproducing more than once) in Atlantic salmon (Salmo salar) is a fitness trait with substantial variation within and among populations. In the Teno River in northern Europe, iteroparous individuals constitute an important component of many populations and have experienced a sharp increase in abundance in the last 20 years, partly overlapping with a general decrease in age structure. The physiological basis of iteroparity bears similarities to that of age at first maturity, another life‐history trait with substantial fitness effects in salmon. Sea age at maturity in Atlantic salmon is controlled by a major locus around the vgll3 gene, and we used this opportunity demonstrate that these two traits are co‐inherited around this genome region. The odds ratio of survival until second reproduction was up to 2.4 (1.8–3.5 90% CI) times higher for fish with the early‐maturing vgll3 genotype (EE) compared to fish with the late‐maturing genotype (LL). The L allele was dominant in individuals remaining only one year at sea before maturation, but the dominance was reversed, with the E allele being dominant in individuals maturing after two or more years at sea. Post hoc analysis indicated that iteroparous fish with the EE genotype had accelerated growth prior to first reproduction compared to first‐time spawners, across all age groups, whereas this effect was not detected in fish with the LL genotype. These results broaden the functional link around the vgll3 genome region and help us understand constraints in the evolution of life‐history variation in salmon. Our results further highlight the need to account for genetic correlations between fitness traits when predicting demographic changes in changing environments.     

Field‐compatible protocol for detecting tetracyclines with bioluminescent bioreporters without pipetting steps

Whole‐cell bioreporters are living organisms and thus using them for detecting environmental contaminants would reflect biological effects of these pollutants. However, bioreporters are not widely used in field studies. Many of the bioreporter field protocols are suitable for liquid samples or include pipetting steps, which is a demanding task outside the laboratory. We present a bioreporter protocol without pipetting or sample type requirements. The protocol utilizes polyester swabs, commonly used in cleanroom technology. As an example contaminant, we used tetracycline and generated test samples with known concentrations up to the maximum tetracycline residue limit of milk set by the European Union (EU) regulation. The matrices of the test samples were Milli‐Q water, milk and soil. The swabs were first dipped in the bioreporter cell cultures and then to test samples and luminescence was measured after incubation. The standard deviation of measurements from ten replicate swabs was in the same range as commonly in pipetting protocols (4–19%). The test samples with lowest tetracycline concentration (5 ng mL^?1) were distinguished from the control samples (0 ng mL^?1 tetracycline). Our results show that swabs can be used together with luminescent whole cell bioreporters, making it possible to conduct the measurements in field conditions.     

Neutrophil Extracellular Traps Confine Pseudomonas aeruginosa Ocular Biofilms and Restrict Brain Invasion

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Complete mitochondrial genome sequence of the Himalayan Griffon,Gyps himalayensis (Accipitriformes: Accipitridae): Sequence,structure, and phylogenetic analyses

This is the first study to describe the mitochondrial genome of the Himalayan Griffon, Gyps himalayensis, which is an Old World vulture belonging to the family Accipitridae and occurring along the Himalayas and the adjoining Tibetan Plateau. Its mitogenome is a closed circular molecule 17,381 bp in size containing 13 protein‐coding genes, 22 tRNA coding genes, two rRNA‐coding genes, a control region (CR), and an extra pseudo‐control region (CCR) that are conserved in most Accipitridae mitogenomes. The overall base composition of the G. himalayensis mitogenome is 24.55% A, 29.49% T, 31.59% C, and 14.37% G, which is typical for bird mitochondrial genomes. The alignment of the Accipitridae species control regions showed high levels of genetic variation and abundant AT content. At the 5′ end of the domain I region, a long continuous poly‐C sequence was found. Two tandem repeats were found in the pseudo‐control regions. Phylogenetic analysis with Bayesian inference and maximum likelihood based on 13 protein‐coding genes indicated that the relationships at the family level were (Falconidae + (Cathartidae + (Sagittariidae + (Accipitridae + Pandionidae))). In the Accipitridae clade, G. himalayensis is more closely related to Aegypius monachus than to Spilornis cheela. The complete mitogenome of G. himalayensis provides a potentially useful resource for further exploration of the taxonomic status and phylogenetic history of Gyps species.     

c-Myc primed mitochondria determine cellular sensitivity to TRAIL-induced apoptosis

Oncogenic c-Myc renders cells sensitive to TRAIL-induced apoptosis, and existing data suggest that c-Myc sensitizes cells to apoptosis by promoting activation of the mitochondrial apoptosis pathway. However, the molecular mechanisms linking the mitochondrial effects of c-Myc to the c-Myc-dependent sensitization to TRAIL have remained unresolved. Here, we show that TRAIL induces a weak activation of procaspase-8 but fails to activate mitochondrial proapoptotic effectors Bax and Bak, cytochrome c release or downstream effector caspase-3 in non-transformed human fibroblasts or mammary epithelial cells. Our data is consistent with the model that activation of oncogenic c-Myc primes mitochondria through a mechanism involving activation of Bak and this priming enables weak TRAIL-induced caspase-8 signals to activate Bax. This results in cytochrome c release, activation of downstream caspases and postmitochondrial death-inducing signaling complex -independent augmentation of caspase-8-Bid activity. In conclusion, c-Myc-dependent priming of the mitochondrial pathway is critical for the capacity of TRAIL-induced caspase-8 signals to activate effector caspases and for the establishment of lethal caspase feedback amplification loop in human cells.     

Rhizavidin from Rhizobium etli: the first natural dimer in the avidin protein family

Rhizobium etli CFN42 is a symbiotic nitrogen-fixing bacterium of the common bean Phaseolus vulgaris. The symbiotic plasmid p42d of R. etli comprises a gene encoding a putative (strept)avidin-like protein, named rhizavidin. The amino acid sequence identity of rhizavidin in relation to other known avidin-like proteins is 20-30%. The amino acid residues involved in the (strept)avidin-biotin interaction are well conserved in rhizavidin. The structural and functional properties of rhizavidin were carefully studied, and we found that rhizavidin shares characteristics with bradavidin, streptavidin and avidin. However, we found that it is the first naturally occurring dimeric protein in the avidin protein family, in contrast with tetrameric (strept)avidin and bradavidin. Moreover, it possesses a proline residue after a flexible loop (GGSG) in a position close to Trp-110 in avidin, which is an important biotin-binding residue. [3H]Biotin dissociation and ITC (isothermal titration calorimetry) experiments showed dimeric rhizavidin to be a high-affinity biotin-binding protein. Its thermal stability was lower than that of avidin; although similar to streptavidin, it was insensitive to proteinase K. The immunological cross-reactivity of rhizavidin was tested with human serum samples obtained from cancer patients exposed to (strept)avidin. No significant cross-reactivity was observed. The biodistribution of the protein was studied by SPECT (single-photon emission computed tomography) imaging in rats. Similarly to avidin, rhizavidin was observed to accumulate rapidly, mainly in the liver. Evidently, rhizavidin could be used as a complement to (strept)avidin in (strept)avidin-biotin technology.