Proinflammatory genotype is associated with the frailty phenotype in the English Longitudinal Study of Ageing

Background: Frailty is a state of increased vulnerability to poor resolution of homeostasis after a stressor event, which increases the risk of adverse outcomes including falls, disability and death. The underlying pathophysiological pathways of frailty are not known but the hypothalamic–pituitary–adrenal axis and heightened chronic systemic inflammation appear to be major contributors. Methods: We used the English Longitudinal Study of Ageing dataset of 3160 individuals over the age of 50 and assessed their frailty status according to the Fried-criteria. We selected single nucleotide polymorphisms in genes involved in the steroid hormone or inflammatory pathways and performed linear association analysis using age and sex as covariates. To support the biological plausibility of any genetic associations, we selected biomarker levels for further analyses to act as potential endophenotypes of our chosen genetic loci. Results: The strongest association with frailty was observed in the Tumor Necrosis Factor (TNF) (rs1800629, P = 0.001198, β = 0.0894) and the Protein Tyrosine Phosphatase, Receptor type, J (PTPRJ) (rs1566729, P = 0.001372, β = 0.09397) genes. Rs1800629 was significantly associated with decreased levels of high-density lipoprotein (HDL) (P = 0.00949) and cholesterol levels (P = 0.00315), whereas rs1566729 was associated with increased levels of HDL (P = 0.01943). After correcting for multiple testing none of the associations remained significant. Conclusions: We provide potential evidence for the involvement of a multifunctional proinflammatory cytokine gene (TNF) in the frailty phenotype. The implication of this gene is further supported by association with the endophenotype biomarker results

Climate versus in-lake processes as controls of the development of community structure in a low-arctic lake (South-West Greenland)

The dominant processes determining biological structure in lakes at millennial timescales are unclear. In this study, we used a multi-proxy approach to determine the relative importance of autogenic versus allogenic processes on the Holocene development of an oligotrophic lake in SW Greenland (66.99º N, 50.97º W). A 14C and 210Pb-dated sediment core covering ~8400 years BP was analysed for organic-inorganic carbon content, pigments, diatoms, chironomids, zooplankton and stable isotopes (13C, 18O). Relationships among the different proxies and a number of independent controlling variables (Holocene temperature, the 8.2 Kyr event, and immigration of Betula nana into the catchment) were explored using redundancy analysis (RDA) independent of time. The main ecological trajectories in the lake biota were captured by ordination first axis sample scores (18 – 32% variance explained). The importance of the arrival of Betula (ca. 6500 yBP) into the catchment was indicated by a series of partial-constrained ordinations, uniquely explaining ~15% of the variance in chironomids and ~9% in pigments. Climate influences on lake biota were strongest during the 8.2 Kyr cooling event, when all proxies responded rapidly although only chironomids had a unique component (in a partial-RDA) explained by the 8.2 Kyr event (8%). Holocene climate explained less variance than either catchment changes or biotic relationships. The sediment record at this site indicates the importance of catchment factors for lake development, the complexity of community trends even in relatively simple systems (invertebrates are the top predators in the lake) and the challenges of deriving palaeoclimate inferences from sediment records in low arctic freshwater lakes

De novo transcriptome assembly and comparative analysis of differentially expressed genes in Prunus dulcis Mill. in response to freezing stress.

Almond (Prunus dulcis Mill.), one of the most important nut crops, requires chilling during winter to develop fruiting buds. However, early spring chilling and late spring frost may damage the reproductive tissues leading to reduction in the rate of productivity. Despite the importance of transcriptional changes and regulation, little is known about the almond's transcriptome under the cold stress conditions. In the current research, we used RNA-seq technique to study the response of the reproductive tissues of almond (anther and ovary) to frost stress. RNA sequencing resulted in more than 20 million reads from anther and ovary tissues of almond, individually. About 40,000 contigs were assembled and annotated de novo in each tissue. Profile of gene expression in ovary showed significant alterations in 5,112 genes, whereas in anther 6,926 genes were affected by freezing stress. Around two thousands of these genes were common altered genes in both ovary and anther libraries. Gene ontology indicated the involvement of differentially expressed (DE) genes, responding to freezing stress, in metabolic and cellular processes. qRT-PCR analysis verified the expression pattern of eight genes randomly selected from the DE genes. In conclusion, the almond gene index assembled in this study and the reported DE genes can provide great insights on responses of almond and other Prunus species to abiotic stresses. The obtained results from current research would add to the limited available information on almond and Rosaceae. Besides, the findings would be very useful for comparative studies as the number of DE genes reported here is much higher than that of any previous reports in this plant