Fragmentation branching ratios of highly excited hydrocarbon molecules CnH and their cations CnH+ (n<4)

We have measured fragmentation branching ratios of neutral CnH and CnH+ cations produced in high velocity (4.5 a.u) collisions between incident CnH+ cations and helium atoms. Electron capture gives rise to excited neutral species CnH and electronic excitation to excited cations CnH+. Thanks to a dedicated set-up, based on coincident detection of all fragments, the dissociation of the neutral and cationic parents were recorded separately and in a complete way. For the fragmentation of CnH, the H-loss channel is found to be dominant, as already observed by other authors. By contrast, the H-loss and C-loss channels equally dominate the two-fragment break up of CnH+ species. For these cations, we provide the first fragmentation data (n > 2). Results are also discussed in the context of astrochemistry

Performance of Coffea arabica F1 hybrids in agroforestry and full-sun cropping systems in comparison with American pure line cultivars

Coffea arabica F1 hybrids derived from crosses between wild Sudan-Ethiopian and American cultivars and propagated by somatic embryogenesis have been obtained in Central America. These new hybrids considerably enhanced the genetic diversity of coffee in the region. We conducted 15 trials to assess whether using hybrids represents substantial genetic progress in terms of productivity in agroforestry and full-sun cropping systems. The new germplasm was grown in the same conditions as the best American cultivar (homozygous pure lines). The results showed that yields of hybrids were earlier and superior to those of American cultivars. The hybrids were also more stable than the American cultivars in all environments. In the agroforestry system, the mean yield of hybrids was 58% higher than that of the American cultivars, while the mean yield of hybrids in the full-sun system was 34% higher. Coffee-based agroforestry systems (AS) are considered effective in protecting the environment in the volcanic cordilleras of Central America. We found that introducing hybrids in coffee-based AS can considerably increase productivity. This finding could be a convincing argument to encourage coffee growers who have adopted the full-sun cropping system to return to agroforestry cropping systems. Finally, the conditions for large-scale dissemination of those new hybrids—which represent a major innovation for C. arabica cropping—was analysed

Potential neoplastic evolution of Vero cells: in vivo and in vitro characterization

Vero cell lines are extensively employed in viral vaccine manufacturing. Similarly to all established cells, mutations can occur during Vero cells in vitro amplification which can result in adverse features compromising their biological safety. To evaluate the potential neoplastic evolution of these cells, in vitro transformation test, gene expression analysis and karyotyping were compared among low- (127 and 139 passages) and high-passage (passage 194) cell lines, as well as transformed colonies (TCs). In vivo tumorigenicity was also tested to confirm preliminary in vitro data obtained for low passage lines and TCs. Moreover, Vero cells cultivated in foetal bovine serum-free medium and derived from TCs were analysed to investigate the influence of cultivation methods on tumorigenic evolution. Low-passage Vero developed TCs in soft agar, without showing any tumorigenic evolution when inoculated in the animal model. Karyotyping showed a hypo-diploid modal chromosome number and rearrangements with no difference among Vero cell line passages and TCs. These abnormalities were reported also in serum-free cultivated Vero. Gene expression revealed that high-passage Vero cells had several under-expressedand a few over-expressed genes compared to low-passage ones.Gene ontology revealed no significant enrichment of pathways related to oncogenic risk. These findings suggest that in vitro high passage, and not culture conditions, induces Vero transformation correlated to karyotype and gene expression alterations. These data, together with previous investigations reporting tumour induction in high-passage Vero cells, suggest the use of low-passage Vero cells or cell lines other than Vero to increase the safety of vaccine manufacturing

A novel canine kidney cell line model for the evaluation of neoplastic development: karyotype evolution associated with spontaneous immortalization and tumorigenicity

The molecular mechanisms underlying spontaneous neoplastic transformation in cultured mammalian cells remain poorly understood, confounding recognition of parallels with the biology of naturally occurring cancer. The broad use of tumorigenic canine cell lines as research tools, coupled with the accumulation of cytogenomic data from naturally occurring canine cancers, makes the domestic dog an ideal system in which to investigate these relationships. We developed a canine kidney cell line, CKB1-3T7, which allows prospective examination of the onset of spontaneous immortalization and tumorigenicity. We documented the accumulation of cytogenomic aberrations in CKB1-3T7 over 24 months in continuous culture. The majority of aberrations emerged in parallel with key phenotypic changes in cell morphology, growth kinetics, and tumor incidence and latency. Focal deletion of CDKN2A/B emerged first, preceding the onset and progression of tumorigenic potential, and progressed to a homozygous deletion across the cell population during extended culture. Interestingly, CKB1-3T7 demonstrated a tumorigenic phenotype in vivo prior to exhibiting loss of contact inhibition in vitro. We also performed the first genome-wide characterization of the canine tumorigenic cell line MDCK, which also exhibited CDKN2A/B deletion. MDCK and CKB1-3T7 cells shared several additional aberrations that we have reported previously as being highly recurrent in spontaneous canine cancers, many of which, as with CDKN2A/B deletion, are evolutionarily conserved in their human counterparts. The conservation of these molecular events across multiple species, in vitro and in vivo, despite their contrasting karyotypic architecture, is a powerful indicator of a common mechanism underlying emerging neoplastic activity. Through integrated cytogenomic and phenotypic characterization of serial passages of CKB1-3T7 from initiation to development of a tumorigenic phenotype, we present a robust and readily accessible model (to be made available through the American Type Culture Collection) of spontaneous neoplastic transformation that overcomes many of the limitations of earlier studies. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10577-015-9474-8) contains supplementary material, which is available to authorized users