PETROLOGICAL CONSTRAINTS ON THE ORIGIN OF PYROXENITE DYKES IN THE LITHOSPHERIC MANTLE OF THE CHESHMEH-BID OPHIOLITIC MASSIF, SOUTHERN IRAN

The Cheshmeh-Bid ophiolitic massif in the Khajeh-Jamali district (Southern Iran) is dominated by harzburgite-dunite tectonites locally intruded by orthopy-roxenite dikes. These latter are composed of dominant coarse orthopyroxene with minor olivine, Cr-spinel, clinopyroxene and amphibole. Estimated equilibrium temperatures for Mg-hornblende and edenitic amphibole reveal a late stage magmatic origin.The Cheshmeh-Bid orthopyroxenites are characterized by very low Al2O3, CaO, Na2O and TiO2 abundances coupled to relatively high MgO and SiO2contents. They display U-shaped REE patterns, selective LILE enrichment and positive Pb and Sr anomalies. The host harzburgites are highly refractory mantle residues resulting from fluid-assisted melting. Field observations and mineral assemblages suggest that the pyroxenites formed by melt injection along fractures within rather cold ambient harzburgites and chromitites at moderate pressure (P > 1 GPa). Based on bulk-rock compositions and mineral chemistry, we infer that the Cheshmeh-Bid orthopyroxenites originated from the intrusion and crystallization of hydrous Si-rich, low-Ca melts with a boninite signature in a supra-subduction environment. Fine-grained neoblastic domains developed in the pyroxenites in response to subsolidus ductile deformation and recrystallization, which were most likely related to the exhumation of the Cheshmeh-Bid ophiolite massif

Multi-stage rodingitization of ophiolitic bodies from Northern Apennines (Italy): Constraints from petrography, geochemistry and thermodynamic modelling

n/

Single-dose palonosetron for prevention of chemotherapy-induced nausea and vomiting in patients with aggressive non-Hodgkin's lymphoma receiving moderately emetogenic chemotherapy containing steroids: results of a phase II study from the Gruppo Italiano per lo Studio dei Linfomi (GISL)

PURPOSE: The control of nausea and vomiting induced by chemotherapy is paramount for overall treatment success in cancer patients. Antiemetic therapy during chemotherapy in lymphoma patients generally consists of anti-serotoninergic drugs and dexamethasone. The aim of this trial was to evaluate the efficacy of a single dose of palonosetron, a second-generation serotonin type 3 (5-HT(3)) receptor antagonist, in patients with aggressive non-Hodgkin's lymphoma receiving moderately emetogenic chemotherapy (MEC) containing steroids. METHODS: Patients received a single intravenous bolus of palonosetron (0.25 mg) before administration of chemotherapy. Complete response (CR) defined as no vomiting and no rescue therapy during overall phase (0-120 h) was the primary endpoint. Complete control (CC) defined as CR and only mild nausea was a secondary endpoint. RESULTS: Eighty-six evaluable patients entered in the study. A CR was observed in 74 patients (86.0%) during the overall phase; the CR during the acute (0-24 h) and delayed (24-120 h) phases was 90.7% and 88.4%, respectively. CC was 89.5% during the acute and 84.9% during the delayed phase; the overall CC was 82.6%. CONCLUSIONS: This was the first trial, which demonstrated the efficacy of a single dose of palonosetron in control CINV in patients with aggressive non-Hodgkin's lymphoma receiving MEC regimen containing steroids

Périgord black truffle genome uncovers evolutionary origins and mechanisms of symbiosis

LetterInternational audienceThe Périgord black truffle ($Tuber\ melanosporum$ Vittad.) and the Piedmont white truffle dominate today's truffle market. The hypogeous fruiting body of $T.\ melanosporum$ is a gastronomic delicacy produced by an ectomycorrhizal symbiont endemic to calcareous soils in southern Europe. The worldwide demand for this truffle has fuelled intense efforts at cultivation. Identification of processes that condition and trigger fruit body and symbiosis formation, ultimately leading to efficient crop production, will be facilitated by a thorough analysis of truffle genomic traits. In the ectomycorrhizal $Laccaria\ bicolor$, the expansion of gene families may have acted as a 'symbiosis toolbox'. This feature may however reflect evolution of this particular taxon and not a general trait shared by all ectomycorrhizal species. To get a better understanding of the biology and evolution of the ectomycorrhizal symbiosis, we report here the sequence of the haploid genome of $T.\ melanosporum$, which at $\sim$125 megabases is the largest and most complex fungal genome sequenced so far. This expansion results from a proliferation of transposable elements accounting for $\sim$58% of the genome. In contrast, this genome only contains $\sim$7,500 protein-coding genes with very rare multigene families. It lacks large sets of carbohydrate cleaving enzymes, but a few of them involved in degradation of plant cell walls are induced in symbiotic tissues. The latter feature and the upregulation of genes encoding for lipases and multicopper oxidases suggest that $T.\ melanosporum$ degrades its host cell walls during colonization. Symbiosis induces an increased expression of carbohydrate and amino acid transporters in both $L.\ bicolor$ and $T.\ melanosporum$, but the comparison of genomic traits in the two ectomycorrhizal fungi showed that genetic predispositions for symbiosis $-$'the symbiosis toolbox'$-$ evolved along different ways in ascomycetes and basidiomycete

Magmatism and mantle evolution in the Northern Apennines: a tale of rifting, oceanization and subduction

The Apennine magmatism from Early Permian to present may be considered as the result of a Wilson cycle. Here, the main stages of this magmatic activity will be reviewed from a mantle source perspective in the framework of the Alpine-Apennine system. The oldest magmatic event is represented by gabbro-derived granulites of Late Variscan age, now occurring as blocks in Late Cretaceous orogenic melanges. Their protholiths were recognized as deep crustal cumulates derived from MOR-type tholeiitic liquids. This event may be related to the extensive magmatic underplating affecting SW Europe in conjuction with lithospheric thinning and orogenic collapse of the Variscan belt. The subsequent Mesozoic continental rifting preceding the opening of the Jurassic Ligurian Tethys was mostly amagmatic. Nevertheless, widespread evidence of melt migration in the ascending lithosphere during passive asthenospheric upwelling is testified in the exhumed mantle bodies from the Northern Apennine ophiolites. Mantle rocks showing a considerable geochemical and isotope heterogeneity were a dominant component of the Ligurian Tethys oceanic lithosphere. In contrast, the short-lived magmatism of the Ligurian Tethys (ca. 160-165 Ma) was characterized by uniform N-MORB signatures, both in marginal and oceanward domains of the basin, which were related to embryonic and slow-spreading ridge type oceanic lithosphere, respectively. The Nd-Hf isotopic contrast between magmatic products and associated mantle rocks (Rampone et al., 1998; Mc Carthy et al., 2015; Barry et al., 2017; this work) is a debated issue, which could reflect the occurrence of inherited subcontinental mantle or ancient depleted domains in the convecting upper mantle. The subduction initiation in the Northern Apennine was not related to igneous activity. No record of island-arc magmatism linked to the Alpine east-dipping subduction stage has been recognized, possibly due to dry, mantle-dominated, subducted lithosphere (Mc Carthy et al., 2018). On the other hand, the collisional calc-alkaline magmatism coheval with the west-dipping Apennine subduction system was found only as clasts in sediments from the nascent orogen (Aveto-Petrignacola Formation). Ancient modifications of mantle sources, possibly related to the previous subduction event, have been proposed for the origin of this magmatism (Mattioli et al., 2012). The imprint of Apennine subduction on mantle sources is strikingly attested by the recent volcanism (< 5 Ma), which includes the unique magmatic associations from Tuscany and Roman provinces. Here, leucite-free (lamproites, shoshonites) and leucite-bearing (kamafugite, leucitite, plagioleucitite) K-rich magmas, were erupted in the former domains, and locally hybridized with anatectic melts. Mantle melting was triggered by post-orogenic extension following the eastward migration of the Adriatic slab. Mantle source modification through recycling of different sedimentary lithologies from the subducted slab may explain the extreme incompatible trace element enrichments and Sr-Pb-Nd-Hf isotopic signatures of the ultrapotassic magmas, coupled with their subduction-related geochemical affinity (Conticelli et al., 2015). References Barry et al., 2017. Sci. Reports 7, 1870 Conticelli et al., 2015. Lithos 232, 174–196 Mattioli et al., 2012. Lithos 134-135, 201–220. Mc Carthy and Muntener, 2015. Geology 43, 255–258 Mc Carthy et al., 2018. Geology 46, 1059–1062 Rampone et al., 1998. Earth Planet. Sci. Lett. 163, 175–18