RECQ1 Helicase Silencing Decreases the Tumour Growth Rate of U87 Glioblastoma Cell Xenografts in Zebrafish Embryos

RECQ1 helicase has multiple roles in DNA replication, including restoration of the replication fork and DNA repair, and plays an important role in tumour progression. Its expression is highly elevated in glioblastoma as compared to healthy brain tissue. We studied the effects of small hairpin RNA (shRNA)-induced silencing of RECQ1 helicase on the increase in cell number and the invasion of U87 glioblastoma cells. RECQ1 silencing reduced the rate of increase in the number of U87 cells by 30%. This corresponded with a 40% reduction of the percentage of cells in the G2 phase of the cell cycle, and an accumulation of cells in the G1 phase. These effects were confirmed in vivo, in the brain of zebrafish (Danio rerio) embryos, by implanting DsRed-labelled RECQ1 helicase-silenced and control U87 cells. The growth of resulting tumours was quantified by monitoring the increase in xenograft fluorescence intensity during a three-day period with fluorescence microscopy. The reduced rate of tumour growth, by approximately 30% in RECQ1 helicase-silenced cells, was in line with in vitro measurements of the increase in cell number upon RECQ1 helicase silencing. However, RECQ1 helicase silencing did not affect invasive behaviour of U87 cells in the zebrafish brain. This is the first in vivo confirmation that RECQ1 helicase is a promising molecular target in the treatment of glioblastoma

New records of Trachelipus vespertilio (Budde-Lund, 1896) (Isopoda, Oniscidea) with a description of the male

Background The existing descriptions of the woodlouse Trachelipus vespertilio are based on a single female collected in Croatia in the nineteenth century. No further information on the occurrence of this species has been reported in published literature and the morphology of the male, which may offer additional reliable diagnostic characters, has remained unknown. New information On the basis of new material collected in Slovenia, a description of the male morphology of T. vespertilio is provided along with a species diagnosis. The rediscovery of this woodlouse after more than a century extends its distribution range to Slovenia

The Mechanical Consequences of the Interplay of Mineral Distribution and Organic Matrix Orientation in the Claws of the Sea Slater Ligia pallasii

Exposed regions of the arthropod exoskeleton have specialized structure and mineral composition. Their study can provide insights into the evolutionary optimization of the cuticle as a material. We determined the structural and compositional features of claws in the crustacean Ligia pallasii using X-ray micro-computed tomography, scanning electron microscopy (SEM), and analytical scanning transmission electron microscopy (STEM). In addition, we used nanoindentation to determine how these features fine-tune the mechanical properties of the claw cuticle. We found that the inner layer of the claw cuticle—the endocuticle—contains amorphous calcium phosphate, while the outer layer—the exocuticle—is not mineralized and contains elevated amounts of bromine. While the chitin–protein fibers in crustacean exoskeletons generally shift their orientation, they are aligned axially in the claws of L. pallasii. As a consequence, the claw cuticle has larger elastic modulus and hardness in the axial direction. We show that amorphous calcium phosphate mineralization and the brominated cuticle are widespread in isopod crustaceans inhabiting terrestrial habitats. We discuss how the features of the claw cuticle may aid in minimizing the likelihood of fracture. Ultimately, our study points out the features that increase the durability of thin skeletal elements

A bibliometric analysis of research on terrestrial isopods

Terrestrial isopods (Oniscidea) are crustaceans that thrive in terrestrial environments. This study provides an overview of the major topics in terrestrial isopod research during the last 70 years in order to provide an example of publication practices in invertebrate zoology and to examine how basic research in this area is transferred to its applications. Co-citation analysis and bibliographic coupling based on citation data from the Web of Science Core Collection was used. Findings show that while research on terrestrial isopods expanded in applicative research prioritised by research policies, basic research continues to flourish. The most productive countries in the field include the major developed economies and several smaller nations. In the smaller countries, as well as in France and Italy, the bulk of woodlouse research is performed at a few institutions with traditions in this field. Some of the most influential works have been published in periodicals or monographs that are not indexed in Web of Science or Scopus and lack impact factors. Conference proceedings represent some of the most influential publications in the field. Our findings indicate that smaller and developing economies make significant contributions in invertebrate zoology if their research organisations can achieve continuity of research on a topic. Another conclusion is that journal metrics may be a misleading descriptor of the impact of studies and researchers in this field. Ultimately, these results identify several examples of how basic research in invertebrate zoology leads to applications with considerable socio-economic impact