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Selection of plant species with a great remediating capacity and a high biomass production is an important step for depolluting soils especially mine soils. Hyperaccumulators are used in phytoextraction for extracting metals from soil to roots and to translocate them to aerial parts. While in phytostabilization that usually requires amendment, metals are accumulated in the plant roots. The purpose of this study is to investigate Oxalis pes-caprae L. tolerance to Pb and As from Pontgibaud mine soil in France amended with compost and/or biochar. Oxalis bulbils were harvested in three sites located around Algiers: (1) an agricultural land in Reghaïa, (2) an area planted with Pines at the USTHB university campus, and (3) the polluted bank of the El Harrach river. The small and medium bulbil sizes were selected from each locality. Concerning the experimental soil, five mixtures of Pontgibaud technosol (P) with amendments compost (C) and biochar (Bc) were prepared: PC, PBc5, PBc10, PBc5 C, PBcC (w/w). The results indicate that amendments alter the soil physico-chemical characteristics and the mobility of metal(loid)s. They also reveal that As and Pb are differently distributed in plant organs. Medium bulbils especially from El Harrach river and the university campus have shown a better growth. Seedlings growth rate has been the highest in Pontgibaud amended with PC and the lowest in PBc10. [ABSTRACT FROM AUTHOR]

Context: The bark beetle, Pityogenes chalcographus, is one of the main pests in Picea abies stands, and it has also been found on other European Pinaceae species. With massive introductions of North American conifer species into European forests, this insect has extended its host range to exotic Pinaceae species. Aim: This study assessed whether a wider host range has influenced the genetic structure of P. chalcographus and has led to host specialization. Methods: Insects were collected from two different regions of France, where eight native and exotic conifer species coexist and were analyzed using mitochondrial and nuclear genetic markers. Results: Considerable haplotypic diversity was observed within the regions and within host species from where P. chalcographus populations were collected. No genetic differentiation, especially with respect to host species associations, could be detected. Moreover, no relationship could be established between closely related P. chalcographus haplotypes and taxonomically related conifer species. Conclusion: The capacity of P. chalcographus for host shifting and dispersal may have played a key role in the rapid extension of its host range. These findings are important for pest management in forests and health and phytosanitary measures in the timber trade, especially for risk assessment in mixed coniferous forests including tree species of major economic importance. [ABSTRACT FROM AUTHOR]

Abstract: Planting exotic conifers offers indigenous forest insects an opportunity to extend their host range and eventually to become significant pests. Knowing the ecological and evolutionary modalities driving the colonisation of exotic tree species by indigenous insects is thus of primary importance. We compared the bark beetle communities (Coleoptera: Curculionidae, Scolytinae) associated with both native and introduced conifers in France. The aim of our study was to estimate the influence of both host- and insect-related factors on the beetles’ likelihood to shift onto new hosts. We considered the influence of host origin (i.e. native vs. exotic), host tree species identity, tree bark thickness and tree taxonomic proximity, as well as insects’ host specificity. A field inventory using trap trees was carried out in two regions in France (Limousin and Jura) during two consecutive years (2006 and 2007) on three European native conifer species [Norway spruce (Picea abies); Scots pine (Pinus sylvestris) and European Silver-fir (Abies alba)] and five North American [Sitka spruce (Picea sitchensis); Eastern white pine (Pinus strobus); Grand fir (Abies grandis); Douglas fir (Pseudotsuga menziesii) and Western red cedar (Thuja plicata)]. A total of 18 indigenous and 2 exotic bark beetle species were collected. All exotic conifer species were colonised by indigenous bark beetle species and no significant difference was observed of the cumulated species richness of the latter between native and exotic tree species (13 vs. 14, P <0.05). The ability of indigenous bark beetles to shift onto exotic conifers appeared to strongly depend on host species (significantly structuring bark beetle assemblages), the presence of phylogenetically related native conifer species and that of similar resources, in combination with insect host specificity. Host tree species status (native or exotic) also seemed to be involved, but its effect did not seem as essential as that of the previous factors. These findings are discussed in terms of adaptation, plasticity and practical aspects of forest management. [Copyright &y& Elsevier]

Coneworms of the genus Dioryctria Zeller include several serious pests of conifer seeds that are notoriously difficult to distinguish as species. We surveyed mitochondrial DNA variation within the abietella species group by sequencing 451 bp of cytochrome oxidase subunit 1 (COI) and 572 bp of cytochrome oxidase subunit 2 (COII) genes from 64 individuals of six major species in the group. In addition to examining phylogenetic relationships within European members of the group, the study focused on the two most damaging species, D. abietivorella Grote from North America and D. abietella Denis & Schiffermüller from Europe and Asia, which have been considered taxonomically synonymous in the past. To detect different levels of divergence, we extensively sampled in seed orchards and natural forests for D. abietella on different hosts. Maximum parsimony and maximum likelihood analyses confirmed the monophyly of the abietella species group and its separation into three clades. The grouping of North American species (clade A) received strong support in both analyses, whereas relationships between clade A and the two European clades were weakly supported. Dioryctria simplicella Heinemann could not be unambiguously separated from D. abietella populations. The diverse haplotypes observed in the network analysis conducted with eight populations of polyphagous D. abietella suggested the presence of two distinct lineages in France. [ABSTRACT FROM AUTHOR]

Pleural mesothelioma usually presents at an advanced, incurable stage. Chemotherapy with platinum–pemetrexed is a standard treatment. We hypothesised that the addition of pembrolizumab to platinum–pemetrexed would improve overall survival in patients with pleural mesothelioma. We did this open-label, international, randomised phase 3 trial at 51 hospitals in Canada, Italy, and France. Eligible participants were aged 18 years or older, with previously untreated advanced pleural mesothelioma, with an Eastern Cooperative Oncology Group performance status score of 0 or 1. Patients were randomly assigned (1:1) to intravenous chemotherapy (cisplatin [75 mg/m2] or carboplatin [area under the concentration-time curve 5–6 mg/mL per min] with pemetrexed 500 mg/m2, every 3 weeks for up to 6 cycles), with or without intravenous pembrolizumab 200 mg every 3 weeks (up to 2 years). The primary endpoint was overall survival in all randomly assigned patients; safety was assessed in all randomly assigned patients who received at least one dose of study therapy. This trial is registered with ClinicalTrials.gov , NCT02784171 , and is closed to accrual. Between Jan 31, 2017, and Sept 4, 2020, 440 patients were enrolled and randomly assigned to chemotherapy alone (n=218) or chemotherapy with pembrolizumab (n=222). 333 (76 %) of patients were male, 347 (79%) were White, and median age was 71 years (IQR 66–75). At final analysis (database lock Dec 15, 2022), with a median follow-up of 16·2 months (IQR 8·3–27·8), overall survival was significantly longer with pembrolizumab (median overall survival 17·3 months [95% CI 14·4–21·3] with pembrolizumab vs 16·1 months [13·1–18·2] with chemotherapy alone, hazard ratio for death 0·79; 95% CI 0·64–0·98, two-sided p=0·0324). 3-year overall survival rate was 25% (95% CI 20–33%) with pembrolizumab and 17% (13–24%) with chemotherapy alone. Adverse events related to study treatment of grade 3 or 4 occurred in 60 (27%) of 222 patients in the pembrolizumab group and 32 (15%) of 211 patients in the chemotherapy alone group. Hospital admissions for serious adverse events related to one or more study drugs were reported in 40 (18%) of 222 patients in the pembrolizumab group and 12 (6%) of 211 patients in the chemotherapy alone group. Grade 5 adverse events related to one or more drugs occurred in two patients on the pembrolizumab group and one patient in the chemotherapy alone group. In patients with advanced pleural mesothelioma, the addition of pembrolizumab to standard platinum–pemetrexed chemotherapy was tolerable and resulted in a significant improvement in overall survival. This regimen is a new treatment option for previously untreated advanced pleural mesothelioma. The Canadian Cancer Society and Merck & Co. [ABSTRACT FROM AUTHOR]