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Insecticide research has often relied on model species for elucidating the resistance mechanisms present in the targeted pests. The accuracy and applicability of extrapolations of these laboratory findings to field conditions varies but, for target site resistance, conserved mechanisms are generally the rule rather than the exception (Perry et al., 2011). The spinosyn class of insecticides appear to fit this paradigm and are a pest control option with many uses in both crop and animal protection. Resistance to spinosyns has been identified in both laboratory-selected and field-collected pest insects. Studies using the model insect, Drosophila melanogaster, have identified the nicotinic acetylcholine receptor subunit, Dα6 as an important target of the insecticide spinosad (Perry et al., 2007; Watson et al., 2010). Field-isolated resistant strains of several agricultural pest insects provide evidence that resistance cases are often associated with mutations in orthologues to Dα6 (Baxter et al., 2010; Puinean et al., 2013). The expression of these receptors is difficult in heterologous systems. In order to examine the biology of the Dα6 receptor subunit further, we used Drosophila as a model and developed an in vivo rescue system. This allowed us to express four different isoforms of Dα6 and show that each is able to rescue the response to spinosad. Regulatory sequences upstream of the Dα6 gene able to rescue the resistance phenotype were identified. Expression of other D. melanogaster subunits revealed that the rescue phenotype appears to be Dα6 specific. We also demonstrate that expression of pest insect orthologues of Dα6 from a variety of species are capable of rescuing the spinosad response phenotype, verifying the relevance of this receptor to resistance monitoring in the field. In the absence of a robust heterologous expression system, this study presents an in vivo model that will be useful in analysing many other aspects of these receptors and their biology.

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In Drosophila melanogaster larvae, the ring gland (RG) is a control center that orchestrates major developmental transitions. It is a composite organ, consisting of the prothoracic gland, the corpus allatum, and the corpora cardiaca, each of which synthesizes and secretes a different hormone. Until now, the RG’s broader developmental roles beyond endocrine secretion have not been explored. RNA sequencing and analysis of a new transcriptome resource from D. melanogaster wandering third instar larval RGs has provided a fascinating insight into the diversity of developmental signaling in this organ. We have found strong enrichment of expression of two gene pathways not previously associated with the RG: immune response and fatty acid metabolism. We have also uncovered strong expression for many uncharacterized genes. Additionally, RNA interference against RG-enriched cytochrome p450s Cyp6u1 and Cyp6g2 produced a lethal ecdysone deficiency and a juvenile hormone deficiency, respectively, flagging a critical role for these genes in hormone synthesis. This transcriptome provides a valuable new resource for investigation of roles played by the RG in governing insect development.

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The TBS could significantly improve the prediction of ICVD risk and should be used in clinical practice and future studies.

Carotid plaque (CP) is associated with cardiovascular and cerebrovascular events. However, population-based studies with a large sample are rare in China, particularly those in the low-income population. We aimed to determine the prevalence of CP and the associated risk factors in the rural areas of northern China. Between April 2014 and June 2014, we recruited 3789 residents aged ≥45 years. B-mode ultrasonography was performed to measure the extent of CP. The prevalence of CP was 40.3% overall, 47.1% in men, and 35.4% in women (P < 0.001). The prevalence of CP increased with increasing age (P < 0.001). The participants with CP were more likely to have hypertension, diabetes, high total cholesterol (TC) levels, and high low-density lipoprotein-cholesterol levels and be a current smoker; however, they were less likely to be obese. Multiple logistic regression analysis, adjusted for confounders, indicated that age, male sex, hypertension, diabetes, current smoking, and high LDL-C levels were the independent risk factors for CP. There was a lower risk of CP with alcohol consumption. The findings suggest that managing the conventional risk factors is crucial to reduce the burden of cardiovascular and cerebrovascular diseases in the low-income population in China.