To delay resistance development to Bacillus thuringiensis (Bt) plants expressing their own insecticide, the application of the Insect Resistance Management strategy called "High Dose/Refuge Strategy" ...(HD/R) is recommended by the US Environmental Protection Agency (US EPA). This strategy was developed for Bt plants expressing one toxin. Presently, however, new Bt plants that simultaneously express two toxins are on the market. We used a mathematical model to evaluate the efficiency of the HD/R strategy for both these Bt toxins. As the current two-toxin Bt plants do not express two new Cry toxins but reuse one toxin already in use with a one-toxin plant, we estimated the spread of resistance when the resistance alleles are not rare. This study assesses: (i) whether the two toxins have to be present in high concentration, and (ii) the impact of the relative size of the refuge zone on the evolution of resistance and population density. We concluded that for Bt plants expressing one toxin, a high concentration is an essential condition for resistance management. For the pyramided Bt plants, one toxin could be expressed at a low titer if the two toxins are used for the first time, and a small refuge zone is acceptable.
Pest categorisation of Platypus apicalis Bragard, Claude; Baptista, Paula; Chatzivassiliou, Elisavet ...
EFSA journal,
June 2022, Volume:
20, Issue:
6
Journal Article
Peer reviewed
Open access
The EFSA Panel on Plant Health performed a pest categorisation of Platypus apicalis (Coleoptera: Curculionidae: Platypodinae), an ambrosia beetle, also known as a pinhole borer, for the EU territory. ...P. apicalis is a polyphagous pest native to New Zealand. The majority of its life cycle is spent inside tree wood, but it does not directly feed on plant tissue, instead larvae and adults feed on a symbiotic fungus (Sporothrix nothofagi which is pathogenic to Nothofagus spp.) vectored by adults and introduced when they bore tunnels into the host. P. apicalis feeds within a wide range of live, often stressed trees, in dead or dying hardwood and softwood trees, and fallen or felled trees. Successful reproduction can occur inside a number of living tree species including Castanea sativa, Pinus spp. and Ulmus spp. P. apicalis is not known to have established outside of New Zealand although findings have been reported in Australia. Whilst there are no records of interceptions of this species in the EU, platypodines are intercepted with solid wood packing material (SWPM) and Platypus species, but not P. apicalis, have been intercepted with wooden logs in Japan. Host plants for planting also provide a potential pathway. Hosts are grown widely across the EU in areas with climates comparable to those in New Zealand where the pest occurs suggesting that conditions in the EU are suitable for its establishment. If introduced into the EU, adults could disperse naturally by flight, perhaps tens or hundreds of metres. The movement of infested wood and host plants for planting within the EU could facilitate spread. Economic impacts in forestry and timber industries would result from the galleries created by P. apicalis and from wood staining caused by the symbiotic fungus. Phytosanitary measures are available to inhibit the entry of P. apicalis. P. apicalis satisfies the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest.
Bark beetles use aggregation pheromones to promote group foraging, thus increasing the chances of an individual to find a host and, when relevant, to overwhelm the defences of healthy trees. When a ...male beetle finds a suitable host, it releases pheromones that attract potential mates as well as other ‘spying’ males, which result in aggregations on the new host. To date, most studies have been concerned with the use of aggregation pheromones by bark beetles to overcome the defences of living, well-protected trees. How insects behave when facing undefended or poorly defended hosts remains largely unknown. The spatio-temporal pattern of resource colonization by the European eight-toothed spruce bark beetle, Ips typographus, was quantified when weakly defended hosts (fallen trees) were attacked. In many of the replicates, colonization began with the insects rapidly scattering over the available surface and then randomly filling the gaps until a regular distribution was established, which resulted in a constant decrease in nearest-neighbour distances to a minimum below which attacks were not initiated. The scattered distribution of the first attacks suggested that the trees were only weakly defended. A minimal theoretical distance of 2.5 cm to the earlier settlers (corresponding to a density of 3.13 attacks dm−2) was calculated, but the attack density always remained lower, between 0.4 and 1.2 holes dm−2, according to our observations.
Large, observational genetic studies are commonly used to identify genetic factors associated with diseases and disease‐related traits. Such cohorts have not been commonly used to identify genetic ...predictors of drug dosing or concentrations, perhaps because of the heterogeneity in drug dosing and formulation, and the random timing of blood sampling. We hypothesized that large sample sizes relative to traditional pharmacokinetic studies would compensate for this variability and enable the identification of pharmacogenetic predictors of drug concentrations. We performed a cross‐sectional, proof‐of‐concept association study to replicate the well‐established association between metoprolol concentrations and CYP2D6 genotype‐inferred metabolizer phenotypes in participants from the Montreal Heart Institute Hospital Cohort undergoing metoprolol therapy. Plasma concentrations of metoprolol and α‐hydroxymetoprolol (α‐OH‐metoprolol) were measured in samples collected randomly regarding the previous metoprolol dose. A total of 999 individuals were included. The metoprolol daily dose ranged from 6.25 to 400 mg (mean 84.3 ± 57.1 mg). CYP2D6‐inferred phenotype was significantly associated with both metoprolol and α‐OH‐metoprolol in unadjusted and adjusted models (all p < 10−14). Models for metoprolol daily dose showed consistent results. Our study suggests that randomly drawn blood samples from biobanks can serve as a new approach to discover genetic associations related to drug concentrations and dosing, with potentially broader implications for genomewide association studies on the pharmacogenomics of drug metabolism.
Pulmonary arterial hypertension (PAH) is a rare complication of systemic lupus erythematosus (SLE).
We identified all patients with SLE and PAH (SLE-PAH) who were enrolled in the French Pulmonary ...Hypertension Registry with a diagnosis confirmed by right heart catheterization (RHC). A control group of 101 patients with SLE without known PAH was selected from SLE expert centers participating in the Pulmonary Hypertension Registry. Survival was estimated by the Kaplan-Meier method. Hazard ratios associated with potential predictors of death were estimated using Cox proportional hazard models.
Of the 69 patients with SLE-PAH identified in the French Pulmonary Hypertension Registry, 51 were included in the study. They did not differ from the control group regarding age, sex, or duration of SLE at the time of the analysis but had a higher frequency of anti-SSA and anti-SSB antibodies. The delay between SLE diagnosis and PAH diagnosis was 4.9 years (range, 2.8-12.9) years. The 3- and 5-year overall survival rates were 89.4% (95% CI, 76.2%-96.5%) and 83.9% (95% CI, 68.8%-92.1%), respectively. The survival rate was significantly better in patients with anti-U1-RNP antibodies (P = .04).
Patients with SLE-PAH have an overall 5-year survival rate of 83.9% after the PAH diagnosis. Anti-SSA/SSB antibodies may be a risk factor for PAH, and the presence of anti-U1-RNP antibodies appears to be a protective factor regarding survival.
Whether preventive inhaled antibiotics may reduce the incidence of ventilator-associated pneumonia is unclear.
In this investigator-initiated, multicenter, double-blind, randomized, controlled, ...superiority trial, we assigned critically ill adults who had been undergoing invasive mechanical ventilation for at least 72 hours to receive inhaled amikacin at a dose of 20 mg per kilogram of ideal body weight once daily or to receive placebo for 3 days. The primary outcome was a first episode of ventilator-associated pneumonia during 28 days of follow-up. Safety was assessed.
A total of 850 patients underwent randomization, and 847 were included in the analyses (417 assigned to the amikacin group and 430 to the placebo group). All three daily nebulizations were received by 337 patients (81%) in the amikacin group and 355 patients (83%) in the placebo group. At 28 days, ventilator-associated pneumonia had developed in 62 patients (15%) in the amikacin group and in 95 patients (22%) in the placebo group (difference in restricted mean survival time to ventilator-associated pneumonia, 1.5 days; 95% confidence interval CI, 0.6 to 2.5; P = 0.004). An infection-related ventilator-associated complication occurred in 74 patients (18%) in the amikacin group and in 111 patients (26%) in the placebo group (hazard ratio, 0.66; 95% CI, 0.50 to 0.89). Trial-related serious adverse effects were seen in 7 patients (1.7%) in the amikacin group and in 4 patients (0.9%) in the placebo group.
Among patients who had undergone mechanical ventilation for at least 3 days, a subsequent 3-day course of inhaled amikacin reduced the burden of ventilator-associated pneumonia during 28 days of follow-up. (Funded by the French Ministry of Health; AMIKINHAL ClinicalTrials.gov number, NCT03149640; EUDRA Clinical Trials number, 2016-001054-17.).
The EFSA Panel on Plant Health performed a pest categorisation of Tetraleurodes perseae (Hemiptera: Aleyrodidae), the red‐banded whitefly, for the territory of the EU. T. perseae is a tropical and ...subtropical species that originated in the Neotropical region and has now spread and established in the USA (California and Florida), Israel and Lebanon. T. perseae is not listed in Commission Implementing Regulation (EU) 2019/2072. It is oligophagous on Lauraceae and most frequently reported on avocado (Persea americana), on which it is considered a minor or secondary pest. No evidence was found indicating damage to other plants. T. perseae larvae develop on the foliage and don’t attack the fruit. The number of generations per year varies between one and ten. High populations may promote the growth of black sooty moulds on the foliage and fruit, and adults feeding on the buds can lead to deformed immature leaves and premature leaf drop. However, T. perseae populations are usually effectively controlled by hymenopteran parasitoids, at least one of which (Cales noacki) is widespread in the EU. The producers of organic avocados in the EU could encourage the use of C. noacki, although occasional outbreaks of T. perseae could temporarily impact the fruit quality. Adults disperse naturally by flying and all stages can be moved over long distances by the trade of infested plant material. Plants for planting provide potential pathways for entry and spread in the EU. Climatic conditions and availability of host plants in southern EU countries are conducive for establishment. Phytosanitary measures are available to reduce the risk. T. perseae satisfies all of the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest. However, this conclusion has a high uncertainty regarding magnitude of potential impact as the insect is a minor and sporadic pest in its current area of distribution.
Production of leukotrienes by 5-lipoxygenase (5-LO) has been linked to unstable atherosclerotic plaques and cardiovascular events. VIA-2291 is a potent 5-LO inhibitor.
In a double-blinded study, 191 ...patients were randomly assigned 3 weeks after an acute coronary syndrome to receive 25, 50, or 100 mg VIA-2291 or placebo daily for 12 weeks. The primary study end point, whole blood stimulated leukotriene LTB4 at trough drug level, was reduced in all VIA-2291 groups (P<0.0001) in a dose-dependent fashion, with approximately 80% inhibition in >90% of patients in the 100-mg group. A significant reduction of urine leukotriene LTE4 was obtained in all dose groups. No serious adverse events were considered related to study drug. A subset of 93 patients who had undergone a 64-slice coronary CT examination at baseline continued on study medication for a total of 24 weeks and underwent a repeat scan. Five of these patients withdrew or were noncompliant and 28 had nonevaluable scans. Among the 60 remaining patients, new coronary plaques were observed in 5 of 18 (27.8%) placebo-treated patients and in 2 of 42 (4.8%) VIA-2291-treated patients (P=0.01). A reduction in noncalcified plaque volume at 24 weeks versus placebo was observed in VIA-2291-treated groups in the 34 of these 60 patients in whom this end point was analyzable (P<0.01).
VIA-2291 reduces leukotriene production at 12 weeks after an acute coronary syndrome. Preliminary data from the CT substudy suggest that such a reduction in leukotriene production may influence atherosclerosis; however, this requires confirmation in a larger study. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00358826.
The EFSA Panel on Plant Health performed a pest categorisation of Thecodiplosis japonensis (Diptera: Cecidomyiidae) for the EU territory. This species is not included in the EU Commission ...Implementing Regulation 2019/2072. T. japonensis Uchida & Inouye is a well‐defined species, native to a large part of Japan, which was introduced to the Republic of Korea and eastern China: Fujian and Shandong. It attacks Pinus densiflora, P. thunbergii and P. luchuensis in Japan; P. densiflora and P. thunbergii in Korea; and P. massoniana in China, and has been observed to attack other two‐needle pine species, including species present in the EU. The pest is univoltine and the adults emerge between May and August. The adults live only for 1 day. Each female oviposits in batches on developing needles. The neonate larvae crawl to the base of the needle fascicle and create a gall in which they feed gregariously by sap sucking. The third‐instar larvae leave the galls in November, overwinter in a cocoon in the soil and pupate at the end of the winter. Degree day models have been developed to predict adult emergence. Survival of overwintering stages is poor below 15°C and above 30°C. The pest can be detected by its symptoms (stunted or dead needles, galls at the base of infected needle fascicles), and identified using morphological characters or the mitochondrial COI gene. T. japonensis is one of the major forest pests in the Republic of Korea, where 1.7 million trees were cut to control it in 2014–2015. It flies uneasily (a few hundred metres) but can be transported in galls on Pinus plants for planting, including artificially dwarfed plants, or with cut branches. Climate matching and host tree distribution suggest that T. japonensis would be able to establish and have an impact in the EU territory. T. japonensis satisfies all the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest.
Le typographe (Ips typographus) est un scolyte (Coléoptère scolytinae) dont l’hôte principal en Europe est l’Epicéa commun. Capable de développer plusieurs générations dans l’année en fonction des ...conditions climatiques, des pullulations sont régulièrement observées après des événements lui offrant d’innombrables sites de reproduction comme les chablis après tempête ou des peuplements affaiblis par des sécheresses. À la suite d’une lente coévolution entre l’insecte et son hôte, le typographe a développé une stratégie de colonisation lui permettant de dépasser les réactions de défense de l’arbre et de coloniser des arbres sains en période de pullulation. Cette caractéristique en fait le plus important tueur d’arbres parmi les insectes en Europe. A la suite de canicules et sécheresses inédites au cours des dernières années, le forestier est confronté à des dommages très importants dans les pessières, dans un contexte socioéconomique tel qu’il est difficile d’intervenir efficacement pour contrer l’épidémie en cours.
PDF
