Molecular systematics, biogeography, and colony fusion in the European dry-wood termites Kalotermes spp. (Blattodea, Termitoidae, Kalotermitidae).

European dry-wood termites belong to the genus Kalotermes (Kalotermitidae), one of the two termite genera in Europe. Until the recent description of two new species, Kalotermes italicus in Italy and Kalotermes phoenicae in the eastern Mediterranean area, Kalotermes flavicollis was the only taxon known in this region. The presence of additional entities, suggested by morphological and physiological variation observed in K. flavicollis, was supported by molecular studies revealing four distinct genetic lineages: lineage A, K. flavicollis sensu strictu, from the Aegean area to Italy; lineage B, in Tuscany; lineage SC, in Sardinia and Corsica; lineage SF, in southern France. Lineages A and B may form mixed colonies, suggesting hybridization. To draw a more detailed picture of Kalotermes evolution and biogeography in Europe, we analyzed samples from previously unsampled areas, such as Spain and southern Italy, by means of the highly informative cox1/trnL/cox2 mitochondrial DNA marker. Overall, phylogenetic analyses confirmed previously identified lineages and taxa, but widened the distribution of the lineage SC to the mainland and of the lineage SF to Spain and Portugal. Results further provided evidence for the synonymy between lineage B and K. italicus. Species delimitation analysis suggested that the three K. flavicollis lineages, as well as K. italicus, can be separate taxa. Data also suggest a possible interspecific hybridization between K. italicus and both K. flavicollis lineages A and SC.

Origin and evolution of the Italian subterranean termite Reticulitermes lucifugus (Blattodea, Termitoidae, Rhinotermitidae).

The Holarctic genus Reticulitermes shows seven species within the Mediterranean Basin. While phylogeny and systematics at continental level has been deeply investigated, a few studies concentrated on local ranges. To gain a clearer picture of the diversity and evolution of the Italian species Reticulitermes lucifugus, we analyzed the mitochondrial cytochrome oxidase II (COII) gene marker in newly collected colonies across the Peninsula. Data were gathered with all R. lucifugus sequences available from previous studies; COII sequences of the closely related Iberian taxa were also added to the data set. Maximum-likelihood, median-joining and statistical parsimony network elaborations on the resulting 119 colonies all agreed in indicating that: (i) the Sardo-Corsican subspecies R. lucifugus corsicus, strictly related to Southern Italian populations (including the Sicilian ones), is phylogenetically closer to the Iberian Reticulitermes grassei; and (ii) R. lucifugus lucifugus peninsular populations are structured into three clusters. The phylogenetic relationships and the biogeography of extant taxa suggest a scenario in which R. lucifugus ancestors colonized the Italian region through the Sardo-Corsican microplate during its Oligocene-Miocene anticlockwise rotation. Moreover, well after the colonization took place, northward range expansion might have produced the presently observed genetic diversity, as inferred from haplotype and nucleotide diversity estimates. On the whole, this study highlights the evolution of Italian Reticulitermes taxa and supports the importance of a wide taxon sampling especially when dealing with organisms easily dispersed by human activities.

Endocytosis and intracellular localisation of type 1 ribosome-inactivating protein saporin-s6.

Saporin-S6 is a single-chain ribosome-inactivating protein (RIP) that has low toxicity in cells and animals. When the protein is bound to a carrier that facilitates cellular uptake, the protein becomes highly and selectively toxic to the cellular target of the carrier. Thus, saporin-S6 is one of the most widely used RIPs in the preparation of immunoconjugates for anti-cancer therapy. The endocytosis of saporin-S6 by the neoplastic HeLa cells and the subsequent intracellular trafficking were investigated by confocal microscopy that utilises indirect immunofluorescence analysis and transmission electron microscopy that utilises a direct assay with gold-conjugated saporin-S6 and an indirect immunoelectron microscopy assay. Our results indicate that saporin-S6 was taken up by cells mainly through receptor-independent endocytosis. Confocal microscopy analysis showed around 30% co-localisation of saporin-S6 with the endosomal compartment and less than 10% co-localisation with the Golgi apparatus. The pathway identified by the immunofluorescence assay and transmission electron microscopy displayed a progressive accumulation of saporin-S6 in perinuclear vesicular structures. The main findings of this work are the following: i) the nuclear localisation of saporin-S6 and ii) the presence of DNA gaps resulting from abasic sites in HeLa nuclei after intoxication with saporin-S6.

Increased serum level of xanthine oxidoreductase in liver transplanted patients.

Xanthine oxidoreductase (XOR) leakage into serum has been observed in various types of liver pathology as well as after liver transplantation (LT). We determined the amount of XOR associated with LT to investigate the changes in serum enzyme level during the LT procedure and the post-operative period. Additionally, we examined whether there was any correlation between XOR levels and the surgical technique. XOR levels were measured by a competitive ELISA. In a first group of patients, the portal vein was flushed before the liver and systemic reperfusions, which occurred simultaneously. In the second group, the graft was flushed with blood from the portal vein before the systemic reperfusion. XOR showed a marked elevation in the caval effluent collected during LT and was higher compared to control serum levels at all time points that were examined after LT. The XOR levels during LT were also higher than samples taken pre-LT or from the portal blood flush before reperfusion. The XOR level was higher in Group 2 than in Group 1. Enhancement of the XOR serum level during LT was not derived from enterocytes, and it should be attributed to enzyme leakage from graft liver cells. We report the elevation of serum XOR during the three weeks following LT for the first time, as well as the influence of the graft reperfusion technique on XOR serum levels.