A single polyploidization event at the origin of the tetraploid genome of Coffea arabica is responsible for the extremely low genetic variation in wild and cultivated germplasm

The genome of the allotetraploid species Coffea arabica L. was sequenced to assemble independently the two component subgenomes (putatively deriving from C. canephora and C. eugenioides) and to perform a genome-wide analysis of the genetic diversity in cultivated coffee germplasm and in wild populations growing in the center of origin of the species. We assembled a total length of 1.536 Gbp, 444 Mb and 527 Mb of which were assigned to the canephora and eugenioides subgenomes, respectively, and predicted 46,562 gene models, 21,254 and 22,888 of which were assigned to the canephora and to the eugeniodes subgenome, respectively. Through a genome-wide SNP genotyping of 736 C. arabica accessions, we analyzed the genetic diversity in the species and its relationship with geographic distribution and historical records. We observed a weak population structure due to low-frequency derived alleles and highly negative values of Taijma's D, suggesting a recent and severe bottleneck, most likely resulting from a single event of polyploidization, not only for the cultivated germplasm but also for the entire species. This conclusion is strongly supported by forward simulations of mutation accumulation. However, PCA revealed a cline of genetic diversity reflecting a west-to-east geographical distribution from the center of origin in East Africa to the Arabian Peninsula. The extremely low levels of variation observed in the species, as a consequence of the polyploidization event, make the exploitation of diversity within the species for breeding purposes less interesting than in most crop species and stress the need for introgression of new variability from the diploid progenitors

Prasugrel Metabolites Inhibit Neutrophil Functions s

ABSTRACT Clopidogrel and prasugrel belong to a thienopyridine class of oral antiplatelet drugs that, after having been metabolized in the liver, can inhibit platelet function by irreversibly antagonizing the P2Y 12 receptor. Furthermore, thienopyridines influence numerous inflammatory conditions, but their effects on neutrophils have not been evaluated, despite the important role of these cells in inflammation. Therefore, we investigated the effect of prasugrel metabolites on neutrophils to further clarify the role of thienopyridines in inflammation. Interestingly, a prasugrel metabolite mixture, produced in vitro using rat liver microsomes, significantly inhibited N-formyl-methionyl-leucylphenylalanine (fMLP)-and platelet-activating factor (PAF)-induced neutrophil activation. More specifically, prasugrel metabolites inhibited neutrophil transmigration, CD16 surface expression, and neutrophil-platelet aggregation. Moreover, prasugrel metabolite pretreatment also significantly decreased fMLP-or PAF-induced extracellular-signal-regulated kinase phosphorylation as well as calcium mobilization. To determine the target of prasugrel in neutrophils, the role of both P2Y 12 and P2Y 13 receptors was studied using specific reversible antagonists, AR-C69931MX and MRS2211, respectively. Neither antagonist had any direct effect on the agonist-induced neutrophil functional responses. Our findings indicate that prasugrel metabolites may directly target neutrophils and inhibit their activation, suggesting a possible explanation for their antiinflammatory effects previously observed. However, these metabolites do not act through either the P2Y 12 or P2Y 13 receptor in neutrophils

Uruk: dalla "Rivoluzione Urbana" alla Teoria dei Sistemi

Childe's "urban revolution" was based on the marxist paradigm of change as resulting from two economic factors: (1) a "pristine" accumulation of capital; (2) its subtraction from private consumption, and destination to common use. American neo-evolutionism substituted the "revolution". model with a gradual increase of complexity, following the trajectory from "chiefdom" to "early state" -- a trajectory however based on modem cases, which are mostly "secondary" and as a matter of fact did not give origin to states. Also the complex explanations in the vein of systems theory do not take into due account the merits of the old theories, nor the specific features of the historical cases. It is suggested that the old Marx-Childe paradigm, with its "revolutionary" tempo and its economic factors, be formulated anew and tested against the enlarged set of data available today

L'élément hourrite dans la Syrie du Nord (c. 1350-1200)

Liverani Mario. L'élément hourrite dans la Syrie du Nord (c. 1350-1200). In: Revue hittite et asianique, Tome 36, 1978. pp. 149-156

Dall'acculturazione alla deculturazione

1. Valutazione del peso dei processi acculturativi e dei contatti esterni rispetto alla dinamica di sviluppo interno nell'area siro-palestinese. 2. Fondo di equivoco e incomprensione sempre presente nei momenti di contatto, utilizzabile quale spia per la ricostruzione dei sistemi ideologici. 3. Canali del contatto : scambio di messaggi ; scambio di beni ; scambio di persone (specialisti, donne) : esempi e valutazione dell'efficacia acculturativa. 4. Periodizzazione tradizionale (I : Età di Ebla ; II : Età di Mari ; III : Età di el-Amarna ; IV : Ferro I-II ; V : Assoggettamento agli imperi) ; periodizzazione acculturativa (I : fase di inculturazione strutturante ; II : fase di contatti bilanciati ; III : fase di deculturazione) ; tentativo di inserimento della dinamica acculturativa in una visione storica globale di stampo demografico-ecologico.Liverani Mario. Dall'acculturazione alla deculturazione. Considerazioni sul ruolo dei contatti politici ed economici nella storia siro-palestinese pre-ellenistica. In: Modes de contacts et processus de transformation dans les sociétés anciennes. Actes du colloque de Cortone (24-30 mai 1981) Rome : École Française de Rome, 1983. pp. 503-522. (Publications de l'École française de Rome, 67