Tracking the global dispersal of a cosmopolitan insect pest, the peach potato aphid

<p>Abstract</p> <p>Background</p> <p>Global commerce and human transportation are responsible for the range expansion of various insect pests such as the plant sucking aphids. High resolution DNA markers provide the opportunity to examine the genetic structure of aphid populations, identify aphid genotypes and infer their evolutionary history and routes of expansion which is of value in developing management strategies. One of the most widespread aphid species is the peach-potato aphid <it>Myzus persicae</it>, which is considered as a serious pest on various crops in many parts of the world. The present study examined the genetic variation of this aphid at a world scale and then related this to distribution patterns. In particular, 197 aphid parthenogenetic lineages from around the world were analysed with six microsatellite loci.</p> <p>Results</p> <p>Bayesian clustering and admixture analysis split the aphid genotypes into three genetic clusters: European <it>M. persicae persicae</it>, New Zealand <it>M. persicae persicae </it>and Global <it>M. persicae nicotianae</it>. This partition was supported by <it>F</it>_STand genetic distance analyses. The results showed two further points, a possible connection between genotypes found in the UK and New Zealand and globalization of <it>nicotianae </it>associated with colonisation of regions where tobacco is not cultivated. In addition, we report the presence of geographically widespread clones and for the first time the presence of a <it>nicotianae </it>genotype in the Old and New World. Lastly, heterozygote deficiency was detected in some sexual and asexual populations.</p> <p>Conclusion</p> <p>The study revealed important genetic variation among the aphid populations we examined and this was partitioned according to region and host-plant. Clonal selection and gene flow between sexual and asexual lineages are important factors shaping the genetic structure of the aphid populations. In addition, the results reflected the globalization of two subspecies of <it>M. persicae </it>with successful clones being spread at various scales throughout the world. A subspecies appears to result from direct selection on tobacco plants. This information highlights the ultimate ability of a polyphagous aphid species to generate and maintain ecologically successful gene combinations through clonal propagation and the role of human transportation and global commerce for expanding their range.</p

Predicting outcomes in rheumatoid arthritis related interstitial lung disease

Aims: To compare radiology-based prediction models in rheumatoid arthritis-related interstitial lung disease (RA-ILD) to identify patients with a progressive fibrosis phenotype.Methods: RAILD patients had CTs scored visually and by CALIPER and forced vital capacity (FVC) measurements. Outcomes were evaluated using three techniques: 1.Scleroderma system evaluating visual ILD extent and FVC values; 2.Fleischer Society IPF diagnostic guidelines applied to RAILD; 3.CALIPER scores of vessel-related structures (VRS). Outcomes were compared to IPF patients.Results: On univariable Cox analysis, all three staging systems strongly predicted outcome: Scleroderma System:HR=3.78, p=9×10-5; Fleischner System:HR=1.98, p=2×10-3; 4.4% VRS threshold:HR=3.10, p=4×10-4 When the Scleroderma and Fleischner Systems were combined, termed the Progressive Fibrotic System (C-statistic=0.71), they identified a patient subset (n=36) with a progressive fibrotic phenotype and similar 4-year survival to IPF.On multivariable analysis, with adjustment for patient age, gender and smoking status, when analysed alongside the Progressive Fibrotic System, the VRS threshold of 4.4% independently predicted outcome (Model C-statistic=0.77).Conclusions: The combination of two visual CT-based staging systems identified 23% of an RAILD cohort with an IPF-like progressive fibrotic phenotype. The addition of a computer-derived VRS threshold further improved outcome prediction and model fit, beyond that encompassed by RAILD measures of disease severity and extent

Global patterns in genomic diversity underpinning the evolution of insecticide resistance in the aphid crop pest Myzus persicae

Abstract: The aphid Myzus persicae is a destructive agricultural pest that displays an exceptional ability to develop resistance to both natural and synthetic insecticides. To investigate the evolution of resistance in this species we generated a chromosome-scale genome assembly and living panel of >110 fully sequenced globally sampled clonal lines. Our analyses reveal a remarkable diversity of resistance mutations segregating in global populations of M. persicae. We show that the emergence and spread of these mechanisms is influenced by host–plant associations, uncovering the widespread co‐option of a host-plant adaptation that also offers resistance against synthetic insecticides. We identify both the repeated evolution of independent resistance mutations at the same locus, and multiple instances of the evolution of novel resistance mechanisms against key insecticides. Our findings provide fundamental insights into the genomic responses of global insect populations to strong selective forces, and hold practical relevance for the control of pests and parasites.Peer reviewedFinal Published versio

Dimethyl fumarate in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Dimethyl fumarate (DMF) inhibits inflammasome-mediated inflammation and has been proposed as a treatment for patients hospitalised with COVID-19. This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple treatments in patients hospitalised for COVID-19 (NCT04381936, ISRCTN50189673). In this assessment of DMF performed at 27 UK hospitals, adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. Between 2 March 2021 and 18 November 2021, 713 patients were enroled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95% of patients received corticosteroids as part of routine care. There was no evidence of a beneficial effect of DMF on clinical status at day 5 (common odds ratio of unfavourable outcome 1.12; 95% CI 0.86-1.47; p = 0.40). There was no significant effect of DMF on any secondary outcome

Dimethyl fumarate in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Dimethyl fumarate (DMF) inhibits inflammasome-mediated inflammation and has been proposed as a treatment for patients hospitalised with COVID-19. This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing multiple treatments in patients hospitalised for COVID-19 (NCT04381936, ISRCTN50189673). In this assessment of DMF performed at 27 UK hospitals, adults were randomly allocated (1:1) to either usual standard of care alone or usual standard of care plus DMF. The primary outcome was clinical status on day 5 measured on a seven-point ordinal scale. Secondary outcomes were time to sustained improvement in clinical status, time to discharge, day 5 peripheral blood oxygenation, day 5 C-reactive protein, and improvement in day 10 clinical status. Between 2 March 2021 and 18 November 2021, 713 patients were enroled in the DMF evaluation, of whom 356 were randomly allocated to receive usual care plus DMF, and 357 to usual care alone. 95% of patients received corticosteroids as part of routine care. There was no evidence of a beneficial effect of DMF on clinical status at day 5 (common odds ratio of unfavourable outcome 1.12; 95% CI 0.86-1.47; p = 0.40). There was no significant effect of DMF on any secondary outcome

Toxicity and Influence of Sublethal Exposure to Sulfoxaflor on the Aphidophagous Predator <i>Hippodamia variegata</i> (Coleoptera: Coccinellidae)

Hippodamia variegata (Goeze), the variegated ladybug, is a predator of many insect pests, especially aphids. Sulfoxaflor is a chemical insecticide that can be used to control many sap-feeding insect pests, for instance, plant bugs and aphids, as an alternative to neonicotinoids in different crops. To improve the combination of the H. variegata and sulfoxaflor in an IPM (integrated pest management) program, we studied the ecological toxicity of the insecticide to the coccinellid predator at sublethal and lethal doses. We examined the influence of sulfoxaflor on larvae of H. variegata using exposure doses of 3, 6, 12, 24, 48 (maximum recommended field rate (MRFR)), and 96 ng a.i. per insect. In a 15-day toxicity test, we observed decreased adult emergence percentage and survival, as well as an increased hazard quotient. The LD50 (dose causing 50% mortality) of H. variegata due to sulfoxaflor decreased from 97.03 to 35.97 ng a.i. per insect. The total effect assessment indicated that sulfoxaflor could be grouped as slightly harmful for H. variegata. Additionally, most of the life table parameters were significantly decreased after exposure to sulfoxaflor. Overall, the results present a negative influence of sulfoxaflor on H. variegata when applied at the recommended field dose for controlling aphids in Greece, which demonstrates that this insecticide may only be employed with care when used in IPM programs

Insecticide resistance in Tephritid flies

a b s t r a c t Tephritid flies attack a large variety of fruits, which constitute highly-priced commodities in many countries. Insecticides have been used extensively for their control. Although resistance development in fruit flies has not kept pace with that in other insects, possibly due to their high mobility and tendency for wide spatial dispersal, recent studies have indicated that selection pressure has now reached the point where resistance is detectable in the field and control may therefore become problematic. The status of resistance to the commonly used insecticides in the most significant Tephritid pests, such as the Mediterranean fruit fly Ceratitis capitata, the oriental fruit fly Bactrocera dorsalis, the olive fly Bactrocera oleae and the melon fly Bactrocera cucurbitae, is reviewed. Emphasis has been placed on the resistance mechanisms that have been elucidated at the biochemical and molecular level. Prospects for using this knowledge alongside genomic information in Tephritidae to develop novel strategies of potential practical importance for resistance management are discussed

Toxicity, Sublethal and Low Dose Effects of Imidacloprid and Deltamethrin on the Aphidophagous Predator Ceratomegilla undecimnotata (Coleoptera: Coccinellidae)

Ceratomegilla undecimnotata (Coleoptera: Coccinellidae) is a common aphidophagous coccinellid predator used in biological control against aphid pests. Knowing toxicity, lethal, and sublethal effects of insecticides on natural enemies is essential in order to incorporate them into Integrated Pest Management (IPM). In the present study, the lethal and sublethal effects of imidacloprid and deltamethrin were evaluated on the fourth instar larvae of C. undecimnotata and subsequently on the full life cycle. Our results strongly suggest that sublethal and low doses of imidacloprid and deltamethrin at LD10 and LD30 affected fourth instar larvae duration time, adult preoviposition period, total preoviposition period, and fecundity. Moreover, the intrinsic (r) and finite (λ) rate of increase and the net reproduction rate (R0) significantly decreased in populations treated with imidacloprid compared to the control population. The data clearly suggest that imidacloprid and deltamethrin have a negative influence on population growth parameters of C. undecimnotata at sublethal and low doses and, therefore, these insecticides should be used with caution within the context of IPM