Genome wide association identifies PPFIA1 as a candidate gene for acute lung injury risk following major trauma

Acute Lung Injury (ALI) is a syndrome with high associated mortality characterized by severe hypoxemia and pulmonary infiltrates in patients with critical illness. We conducted the first investigation to use the genome wide association (GWA) approach to identify putative risk variants for ALI. Genome wide genotyping was performed using the Illumina Human Quad 610 BeadChip. We performed a two-stage GWA study followed by a third stage of functional characterization. In the discovery phase (Phase 1), we compared 600 European American trauma-associated ALI cases with 2266 European American population-based controls. We carried forward the top 1% of single nucleotide polymorphisms (SNPs) at p<0.01 to a replication phase (Phase 2) comprised of a nested case-control design sample of 212 trauma-associated ALI cases and 283 at-risk trauma non-ALI controls from ongoing cohort studies. SNPs that replicated at the 0.05 level in Phase 2 were subject to functional validation (Phase 3) using expression quantitative trait loci (eQTL) analyses in stimulated B-lymphoblastoid cell lines (B-LCL) in family trios. 159 SNPs from the discovery phase replicated in Phase 2, including loci with prior evidence for a role in ALI pathogenesis. Functional evaluation of these replicated SNPs revealed rs471931 on 11q13.3 to exert a cis-regulatory effect on mRNA expression in the PPFIA1 gene (p = 0.0021). PPFIA1 encodes liprin alpha, a protein involved in cell adhesion, integrin expression, and cell-matrix interactions. This study supports the feasibility of future multi-center GWA investigations of ALI risk, and identifies PPFIA1 as a potential functional candidate ALI risk gene for future research.     

Habitat quality favoured over familiarity: a rejection of natal habitat preference induction in the mosquito Aedes albopictus

1. Natal habitat preference induction (NHPI) is a behavioural phenomenon in which offspring show a change in preference in adult oviposition choice as a function of experience as an immature. 2. Although well known in certain systems, such as herbivorous insects, this behaviour has not been well studied in aquatic insects. 3. The container–breeding mosquito, Aedes albopictus (Skuse) was used to test if NHPI occurs in aquatic insects under natural conditions of two leaf species as a nutritive base (Juniperus virginiana L. and Quercus virginiana Mill) and two larval densities. 4. Significant effects of leaf species and density on adult mosquito attributes were found, with J. virginiana and low larval density associated with more, faster developing, larger and more fecund mosquitoes. However, no evidence for NHPI was found. Instead a canalised behavior was found that included spreading eggs between high– and low–quality oviposition choices in the same proportions regardless of larval experience.     

Evaluation of resistance to different insecticides in field strains of Helicoverpa armigera (Lepidoptera: Noctuidae) in Punjab, Pakistan

Susceptibility of field populations of Helicoverpa armigera (Lepidoptera: Noctuidae) from Punjab, Pakistan to selected insecticides was evaluated using the leaf dip method. The resistance factors varied between populations. The general trends were low to moderate resistance to endosulfan; very low to low resistance to chlorpyrifos and profenofos; very low resistance to spinosad, indoxacarb and thiodicarb; moderate to high resistance to bifenthrin; high to very high resistance to cypermethrin; and very high resistance to lambda-cyhalothrin. Integrated pest management strategies aimed at reducing pesticide application, such as rotating the conventional insecticides having low resistance with newly developed synthetic insecticides and conserving natural enemies, are recommended.     

Long-term fire frequency variability in the eastern Canadian boreal forest: the influences of climate vs. local factors

The influence of climatic and local nonclimatic factors on the fire regime of the eastern Canadian boreal forest over the last 8000 years is investigated by examining charred particles preserved in four lacustrine deposits. Herein, we compare the distribution of fire-free intervals (FFIs) and the synchronicity of fire events among sites, using Ripley's K -function to determine the extent of the role of local-scale vs. large-scale processes with respect to fire control. Between 8000 and 5800 cal. bp (calibrated years before present) the climatic and ecological conditions were less conducive to fire events than after this date. After 5800 cal. bp , the number of fires per 1000 years (fire frequency) progressively increased, reaching a maximum ca. 3400 cal. bp . There was a sharp decrease in fire frequency during the last 800 years. Between 8000 and 4000 cal. bp , comparable FFIs and synchronous fire episodes were determined for the study sites. During this period, the fire frequency was predominantly controlled by climate. After 4000 cal. bp , two sites displayed independent fire histories (different FFI distributions or asynchronous fire events), underlining the important influence of local factors, including short-term fuel wetness, characteristics of the watershed and landscape connectivity, in determining fire occurrence. We conclude that climatic changes occurred during the last 4000 years that induced a rise in the water table; this may explain the high spatial heterogeneity in fire history. Current and projected global climatic changes may cause similar spatial variability in fire frequency.     

Floral biology and pollen viability of parental lines of onion hybrids

Parental lines (inbred and hybrid male-sterile lines and inbred pollinators) of prospective F, hybrids from the NVRS spring-sown bulb onion breeding programme were examined to study their floral biology and aspects of pollination under glasshouse conditions. Inbreeding depression occurred in both pollinator and male-sterile inbreds in terms of reduced flower numbers per umbel and a greater proportion of defective pistils. Male-sterile and male-fertile lines differed in their stigma and style characteristics and pattern of development. At flower opening, the styles of male-sterile lines were longer and the stigmatic knob became receptive relatively sooner. The inbred male-sterile line II/3 ms appeared to have a reduced receptive area on its stigmatic knob and remained receptive for a relatively shorter period. Individual lines differed for time of flowering, nectar content and its sugar concentration, and in their effectiveness as male and female parents as judged from pollen tube growth down the style in specific pairings. Assessment of pollen viability using the fluorescein diacetate test did not correlate with assessments based on pollen grain germination and subsequent growth down the style, perhaps as a result of differential receptivity in the inbred lines tested. These results are discussed in relation to future hybrid seed production.     

Effect of water deficit on the cell wall of the date palm (Phoenix dactylifera ‘Deglet nour’, Arecales) fruit during development

Date palm (Phoenix dactylifera) is an important crop providing a valuable nutrition source for people in many countries including the Middle East and North Africa. In recent years, the amount of rain in North Africa and especially in the Tunisian palm grove areas has dropped significantly. We investigated the growth and cell wall remodelling of fruits harvested at three key development stages from trees grown with or without water supply. During development, cell wall solubilization and remodelling was characterized by a decrease of the degree of methylesterification of pectin, an important loss of galactose content and a reduction of the branching of xylan by arabinose in irrigated condition. Water deficit had a profound effect on fruit size, pulp content, cell wall composition and remodelling. Loss of galactose content was not as important, arabinose content was significantly higher in the pectin‐enriched extracts from non‐irrigated condition, and the levels of methylesterification of pectin and O‐acetylation of xyloglucan were lower than in irrigated condition. The lower levels of hydrophobic groups (methylester and O‐acetyl) and the less intensive degradation of the hydrophilic galactan, arabinan and arabinogalactan in the cell wall may be implicated in maintaining the hydration status of the cells under water deficit.