Identification of tammar wallaby SIRH12, derived from a marsupial-specific retrotransposition event

In humans and mice, there are 11 genes derived from sushi-ichi related retrotransposons, some of which are known to play essential roles in placental development. Interestingly, this family of retrotransposons was thought to exist only in eutherian mammals, indicating their significant contributions to the eutherian evolution, but at least one, PEG10, is conserved between marsupials and eutherians. Here we report a novel sushi-ichi retrotransposon-derived gene, SIRH12, in the tammar wallaby, an Australian marsupial species of the kangaroo family. SIRH12 encodes a protein highly homologous to the sushi-ichi retrotransposon Gag protein in the tammar wallaby, while SIRH12 in the South American short-tailed grey opossum is a pseudogene degenerated by accumulation of multiple nonsense mutations. This suggests that SIRH12 retrotransposition occurred only in the marsupial lineage but acquired and retained some as yet unidentified novel function, at least in the lineage of the tammar wallaby.     

Throwing the baby out with the bathwater: does laurel forest restoration remove a critical winter food supply for the critically endangered Azores bullfinch?

The invasive Clethra arborea has a dual-role in the diet of the Azores bullfinch, a critically endangered bird species endemic to the island of São Miguel (Azores, Portugal). This is a crucial winter food resource but it lowers the availability of native laurel forest species that compose most of the bird’s diet throughout the year. The removal of this and other invasive alien species is part of current laurel forest habitat restoration programmes, disregarding the impact on the Azores bullfinch population. In order to evaluate the first responses of the Azores bullfinch to habitat restoration, we studied bird diet, foraging behaviour, food availability and habitat occupancy in managed (without C. arborea) and control areas. Significant increases in the availability of native food resources in managed areas were noticeable in the diet, particularly the intake of Ilex perado ssp. azorica and Prunus lusitanica ssp. azorica flower buds. In most of the studied months birds heavily used and foraged in managed over control areas. The one exception was in December, when a resource-gap occurred in managed areas, which may be overcome in the short-term due to re-establishment of native plants following removal of invasive aliens.     

Insect attraction to synthetic herbivore‐induced plant volatile‐treated field crops

• 1 Plants produce natural enemy‐attracting semiochemicals known as herbivore‐induced plant volatiles (HIPV) in response to herbivore damage. Deployment of synthetic HIPV in crops could enhance the biological control of pests. To test this, six HIPV [methyl salicylate (MeSA), methyl anthranilate (MeA), methyl jasmonate (MeJA), benzaldehyde (Be), cis‐3‐hexenyl acetate (HA), cis‐hexen‐1‐ol (He)] in three concentrations (0.5%, 1.0% and 2.0% v/v) mixed with a vegetable oil adjuvant, Synertrol® (Organic Crop Protectants Pty Ltd, Australia), were sprayed onto winegrape, broccoli and sweet corn plants.
• 2 The relative abundance of insects within treated plots was assessed with non‐attracting, transparent sticky traps at varying time intervals up to 22 days after spraying.
• 3 In the vineyard experiment, Trichogrammatidae responded to Be and MeA (0.5%) and Be (1.0%); Encyrtidae and Bethylidae responded to MeA (1.0%); Scelionidae responded to all compounds at 1.0% and 2.0%; and predatory insects responded to MeA. In sweet corn, parasitoids as a group and Encyrtidae responded to MeA (0.5%); Braconidae responded to all compounds at 0.5% and Synertrol‐only; thrips responded to all compounds at 0.5% and 1.0%; while all parasitoids responded to all compounds at 0.5% and 1.0% and Synertrol‐only. In broccoli, parasitoids as a group and Scelionidae responded to Be, HA, He and Synertrol‐only; Trichogrammatidae responded to Be (0.5%), He (0.5% and 1.0%), MeJA (1.0%) and MeSA (0.5%); and thrips responded to all compounds at to 0.5% and 1.0%.
• 4 Significant attraction of insects occurred up to 6 days after the HIPV application, suggesting that plants may have been induced to produce endogenous volatiles that attracted insects over an extended period.
• 5 The results obtained are discussed in relation to the potential utility of synthetic HIPV to enhance the biological control of pests.

     

The interrelationship between crypsis and colour polymorphism

The mechanisms behind the evolution and maintenance of conspicuous visible polymorphisms comprising tens of morphs present a challenge to evolutionary theory. However, for cryptic forms Endler (Evol. Biol., 11, 1978, 319) conjectured that complex backgrounds facilitate polymorphism because in such habitats there are several ways to resemble the resting surface. We use computer simulation to explore the evolution of cryptic morphs on increasingly complex backgrounds under regimes that include selection for crypsis, apostatic predation and dietary wariness. We show that there is a monotonic increase in the number of morphs evolving in a population as the potential number of cryptic morphs increases. The relationship is very weak with selection for crypsis alone, but much stronger with the addition of apostatic selection. In contrast, when dietary wariness is added to the model the plot of number of morphs maintained, as a function of the potential number of cryptic forms available, is minimized at an intermediate number of cryptic forms, i.e. is V-shaped. These counter-intuitive patterns are robust to varying strengths of apostatic selection and different implementations of dietary wariness, and are more pronounced when predator and prey generation lengths are similar.     

Conformational plasticity of proNGF

Nerve Growth Factor is an essential protein that supports neuronal survival during development and influences neuronal function throughout adulthood, both in the central and peripheral nervous system. The unprocessed precursor of NGF, proNGF, seems to be endowed with biological functions distinct from those of the mature protein, such as chaperone-like activities and apoptotic and/or neurotrophic properties. We have previously suggested, based on Small Angle X-ray Scattering data, that recombinant murine proNGF has features typical of an intrinsically unfolded protein. Using complementary biophysical techniques, we show here new evidence that clarifies and widens this hypothesis through a detailed comparison of the structural properties of NGF and proNGF. Our data provide direct information about the dynamic properties of the pro-peptide and indicate that proNGF assumes in solution a compact globular conformation. The N-terminal pro-peptide extension influences the chemical environment of the mature protein and protects the protein from proteolytic digestion. Accordingly, we observe that unfolding of proNGF involves a two-steps mechanism. The distinct structural properties of proNGF as compared to NGF agree with and rationalise a different functional role of the precursor.     

Treating seeds with activators of plant defence generates long-lasting priming of resistance to pests and pathogens

? Priming of defence is a strategy employed by plants exposed to stress to enhance resistance against future stress episodes with minimal associated costs on growth. Here, we test the hypothesis that application of priming agents to seeds can result in plants with primed defences. ? We measured resistance to arthropod herbivores and disease in tomato (Solanum lycopersicum) plants grown from seed treated with jasmonic acid (JA) and/or β-aminobutryric acid (BABA). ? Plants grown from JA-treated seed showed increased resistance against herbivory by spider mites, caterpillars and aphids, and against the necrotrophic fungal pathogen, Botrytis cinerea. BABA seed treatment provided primed defence against powdery mildew disease caused by the biotrophic fungal pathogen, Oidium neolycopersici. Priming responses were long-lasting, with significant increases in resistance sustained in plants grown from treated seed for at least 8 wk, and were associated with enhanced defence gene expression during pathogen attack. There was no significant antagonism between different forms of defence in plants grown from seeds treated with a combination of JA and BABA. ? Long-term defence priming by seed treatments was not accompanied by reductions in growth, and may therefore be suitable for commercial exploitation.     

Australian native flowering plants enhance the longevity of three parasitoids of brassica pests

Floral resources from native plants that are adapted to the local environment could be more advantageous than the use of nonnative plants. In Australia, there is a dearth of information on the benefits of native plants to natural enemies and their selectivity against pests. Accordingly, we examined the longevity of the parasitoids Diaeretiella rapae (McIntosh) and Cotesia glomerata (L.) (both Hymenoptera: Braconidae), and Diadegma semiclausum (Hellen) (Hymenoptera: Ichneumonidae) exposed to flowering shoots from Australian native plants which was compared with the nonnative buckwheat (Fagopyrum esculentum), often used in conservation biological control. Longevity of parasitoids was significantly enhanced by the Australian natives Westringia fruticosa, Mentha satureioides, Callistemon citrinus, Leptospermum cv. ‘Rudolph’, Grevillea cv. ‘Bronze Rambler’, Myoporum parvifolium, Lotus australis, and nonnative F. esculentum. The highest mean survival by native plant species was 3.4× higher for D. rapae with Leptospermum sp. and 4.3× higher for D. semiclausum with M. parvifolium. For C. glomerata, Grevillea sp. increased longevity by 6.9× compared with water only. Longevity of Plutella xylostella (L.) (Lepidoptera: Plutellidae), a major crop pest, was enhanced by all plants against which it was screened except Acacia baileyana, a species that had no effect on parasitoid longevity. Several Australian native plant species that benefit parasitoids were identified. None of the plant species provided a selective benefit to the parasitoid D. semiclausum compared with its host P. xylostella; however, the benefit of M. parvifolium and Grevillea sp. on the longevity of D. semiclausum was relatively higher compared with the pest. These results suggest the need for field studies to determine whether native Australian plants increase P. xylostella impact in nearby brassica crops.     

Assessing the Assessment in Emergency Care Training

Objective

Each year over 1.5 million health care professionals attend emergency care courses. Despite high stakes for patients and extensive resources involved, little evidence exists on the quality of assessment. The aim of this study was to evaluate the validity and reliability of commonly used formats in assessing emergency care skills.

Methods

Residents were assessed at the end of a 2-week emergency course; a subgroup was videotaped. Psychometric analyses were conducted to assess the validity and inter-rater reliability of the assessment instrument, which included a checklist, a 9-item competency scale and a global performance scale.

Results

A group of 144 residents and 12 raters participated in the study; 22 residents were videotaped and re-assessed by 8 raters. The checklists showed limited validity and poor inter-rater reliability for the dimensions “correct” and “timely” (ICC = .30 and.39 resp.). The competency scale had good construct validity, consisting of a clinical and a communication subscale. The internal consistency of the (sub)scales was high (α = .93/.91/.86). The inter-rater reliability was moderate for the clinical competency subscale (.49) and the global performance scale (.50), but poor for the communication subscale (.27). A generalizability study showed that for a reliable assessment 5–13 raters are needed when using checklists, and four when using the clinical competency scale or the global performance scale.

Conclusions

This study shows poor validity and reliability for assessing emergency skills with checklists but good validity and moderate reliability with clinical competency or global performance scales. Involving more raters can improve the reliability substantially. Recommendations are made to improve this high stakes skill assessment.     

Mechanisms linking diabetes mellitus to the development of atherosclerosis: a role for endoplasmic reticulum stress and glycogen synthase kinase-3

Recent decades have seen a significant increase in the incidence of diabetes mellitus. The number of individuals with diabetes is projected to reach 300 million by the year 2025. Diabetes is a leading cause of blindness, renal failure, lower limb amputation, and an independent risk factor for atherosclerotic cardiovascular disease (CVD)--a leading cause of death in Western society. Understanding the molecular and cellular mechanisms by which diabetes mellitus promotes atherosclerosis is essential to developing methods to treat and prevent diabetes-associated CVD. This review summarizes our current knowledge of the mechanisms by which diabetes may promote atherogenesis and specifically focuses on a novel pathway linking these 2 conditions. We hypothesize that the accumulation of intracellular glucosamine observed in conditions of chronic hyperglycaemia may promote atherogenesis via a mechanism involving dysregulated protein folding, activation of endoplasmic reticulum (ER) stress, and increased glycogen synthase kinase (GSK)-3 activity. The identification of this novel mechanism provides a promising hypothesis and multiple new targets for potential therapeutic intervention in the treatment of diabetes mellitus and accelerated atherosclerosis.