Adenovirus vectors can induce activation of endothelial cells: CD40-CD40L interactions partly participate in the endothelial cells activation induced by adenovirus vectors in an NF-kappaB-dependent manner

Replication-defective adenovirus vector without both E1 and E3 is one of the most popular tools in transgenic therapies. However, more attention should be paid to adenovirus vectors mediated-gene modified study on endothelial cells (ECs). To verify the possible danger in that process, we explored the effect of adenovirus on ECs in this study. By using western blot analysis, we showed that the level of both CD40 and CD40L on human umbilical vein endothelial cells (HUVECs) were upregraduated by adenovirus vector infection at 100 multiplicity of infection (MOI). The activation of ECs induced by adenovirus vector infection at MOI 100 can be partly inhibited by a blockade of CD40/CD40L interactions by using the recombinant adenovirus Ad-sCD40LIg or an anti-CD40L monoclonal antibody (mAb) in vitro. On ECs, blockade of CD40/CD40L decreased the expression of IL (interleukin)-6, IL-8 and intercellular adhesion molecule (ICAM) in adenovirus vector-induced cells. In electrophoretic mobility shift assay (EMSA), both Ad-sCD40LIg and anti-CD40L mAb can attenuate the activity of NF-kappaB (NF-κB) pathway contributing to the activation of ECs, which indicated that CD40-CD40L interactions played significant role in the activation of ECs induced by adenovirus vectors via an NF-κB pathway. Our study provide evidences for a supplementary mechanism of the ECs activation induced by adenovirus vector infection and suggests that CD40-CD40L interactions partly participate in the ECs activation induced by adenovirus vectors in an NF-κB-dependent manner.Key words: Adenovirus vector, CD40, CD40L, endothelial cells, NF-kappaB

Vertex importance extension of betweenness centrality algorithm

Variety of real-life structures can be simplified by a graph. Such simplification emphasizes the structure represented by vertices connected via edges. A common method for the analysis of the vertices importance in a network is betweenness centrality. The centrality is computed using the information about the shortest paths that exist in a graph. This approach puts the importance on the edges that connect the vertices. However, not all vertices are equal. Some of them might be more important than others or have more significant influence on the behavior of the network. Therefore, we introduce the modification of the betweenness centrality algorithm that takes into account the vertex importance. This approach allows the further refinement of the betweenness centrality score to fulfill the needs of the network better. We show this idea on an example of the real traffic network. We test the performance of the algorithm on the traffic network data from the city of Bratislava, Slovakia to prove that the inclusion of the modification does not hinder the original algorithm much. We also provide a visualization of the traffic network of the city of Ostrava, the Czech Republic to show the effect of the vertex importance adjustment. The algorithm was parallelized by MPI (http://www.mpi-forum.org/) and was tested on the supercomputer Salomon (https://docs.it4i.cz/) at IT4Innovations National Supercomputing Center, the Czech Republic.808726

High-level production of violacein by the newly isolated Duganella violaceinigra str. NI28 and its impact on Staphylococcus aureus

A violacein-producing bacterial strain was isolated and identified as a relative of Duganella violaceinigra YIM 31327 based upon phylogenetic analyses using the 16S rRNA, gyrB and vioA gene sequences and a fatty acid methyl ester (FAME) analysis. This new strain was designated D. violaceinigra str. NI28. Although these two strains appear related based upon these analyses, the new isolate was phenotypically different from the type strain as it grew 25% faster on nutrient media and produced 45-fold more violacein. When compared with several other violacein producing strains, including Janthinobacterium lividum, D. violaceinigra str. NI28 was the best violacein producer. For instance, the crude violacein yield with D. violaceinigra str. NI28 was 6.0 mg/OD at 24 hours, a value that was more than two-fold higher than all the other strains. Finally, the antibacterial activity of D. violaceinigra str. NI28 crude violacein was assayed using several multidrug resistant Staphylococcus aureus. Addition of 30 mu M crude violacein led to a 96% loss in the initial S. aureus population while the minimum inhibitory concentration was 1.8 mu M. Consequently, this novel isolate represents a phenotypic variant of D. violaceinigra capable of producing much greater quantities of crude violacein, an antibiotic effective against multidrug resistant S. aureusopen

Superelasticity of Carbon Nanocoils from Atomistic Quantum Simulations

A structural model of carbon nanocoils (CNCs) on the basis of carbon nanotubes (CNTs) was proposed. The Young’s moduli and spring constants of CNCs were computed and compared with those of CNTs. Upon elongation and compression, CNCs exhibit superelastic properties that are manifested by the nearly invariant average bond lengths and the large maximum elastic strain limit. Analysis of bond angle distributions shows that the three-dimensional spiral structures of CNCs mainly account for their unique superelasticity

Benchmarking the Self-Assembly of Surfactin Biosurfactant at the Liquid–Air Interface to those of Synthetic Surfactants

The adsorption of surfactin, a lipopeptide biosurfactant, at the liquid–air interface has been investigated in this work. The maximum adsorption density and the nature and the extent of lateral interaction between the adsorbed surfactin molecules at the interface were estimated from surface tension data using the Frumkin model. The quantitative information obtained using the Frumkin model was also compared to those obtained using the Gibbs equation and the Langmuir–Szyszkowski model. Error analysis showed a better agreement between the experimental and the calculated values using the Frumkin model relative to the other two models. The adsorption of surfactin at the liquid–air interface was also compared to those of synthetic anionic, sodium dodecylbenzenesulphonate (SDBS), and nonionic, octaethylene glycol monotetradecyl ether (C14E8), surfactants. It has been estimated that the area occupied by a surfactin molecule at the interface is about 3- and 2.5-fold higher than those occupied by SDBS and C14E8 molecules, respectively. The interaction between the adsorbed molecules of the anionic biosurfactant (surfactin) was estimated to be attractive, unlike the mild repulsive interaction between the adsorbed SDBS molecules

Clinicopathological significance of homeoprotein Six1 in hepatocellular carcinoma

Tumour recurrence and metastases of hepatocellular carcinoma (HCC) after hepatectomy are the major obstacles of long-term survival. The present study investigated the clinicopathological significance of a possible metastasis regulator Six1 in HCC patients who were undergone hepatectomy. Seventy-two pairs of RNA and 103 pairs of protein from tumour and adjacent nontumour liver tissues of HCC patients were examined. About 85 and 60% of HCC tumour tissues were found to overexpress Six1 mRNA and protein, respectively, compared with nontumour liver tissues. No Six1 protein was detected in HCC nontumour liver tissues and normal liver tissues. Increased Six1 protein expression in HCC patients was significantly correlated with pathologic tumour-node-metastasis (pTNM) stage (P=0.002), venous infiltration (P=0.004) and poor overall survival (P=0.0423). We concluded that Six1 is frequently overexpressed in HCC patients and elevated Six1 protein in HCC patients may be an indication of advanced stage and poor overall survival after hepatectomy

Regulation of Pax6 by CTCF during Induction of Mouse ES Cell Differentiation

Pax6 plays an important role in embryonic cell (ES) differentiation during embryonic development. Expression of Pax6 undergoes from a low level to high levels following ES cell differentiation to neural stem cells, and then fades away in most of the differentiated cell types. There is a limited knowledge concerning how Pax6 is regulated in ES cell differentiation. We report that Pax6 expression in mouse ES cells was controlled by CCCTC binding factor (CTCF) through a promoter repression mechanism. Pax6 expression was significantly enhanced while CTCF activity was kept in the constant during ES cell differentiation to radial glial cells. Instead, the interaction of CTCF with Pax6 gene was regulated by decreased CTCF occupancy in its binding motifs upstream from Pax6 P0 promoter following the course of ES cell differentiation. Reduced occupancy of CTCF in the binding motif region upstream from the P0 promoter was due to increased DNA methylations in the CpG sites identified in the region. Furthermore, changes in DNA methylation levels in vitro and in vivo effectively altered methylation status of these identified CpG sites, which affected ability of CTCF to interact with the P0 promoter, resulting in increases in Pax6 expression. We conclude that there is an epigenetic mechanism involving regulations of Pax6 gene during ES cell differentiation to neural stem cells, which is through increases or decreases in methylation levels of Pax6 gene to effectively alter the ability of CTCF in control of Pax6 expression, respectively