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Summary Increased vascular permeability and leakage are hallmarks of several pathologies and determine disease progression and severity by facilitating inflammatory/metastatic cell infiltration. Using tissue-specific genetic ablation in endothelial cells, we have investigated in vivo the role of Tumor progression locus 2 (Tpl2), a mitogen-activated protein kinase kinase kinase (MAP3K) member with pleiotropic effects in inflammation and cancer. In response to proinflammatory stimuli, endothelial Tpl2 deletion alters tight junction claudin-5 protein expression through inhibition of JNK signaling and lysosomal degradation activation, resulting in reduced vascular permeability and immune cell infiltration. This results in significantly attenuated disease scores in experimental autoimmune encephalomyelitis and fewer tumor nodules in a hematogenic lung cancer metastasis model. Accordingly, pharmacologic inhibition of Tpl2 or small interfering RNA (siRNA)-mediated Tpl2 knockdown recapitulates our findings and reduces lung metastatic tumor invasions. These results establish an endothelial-specific role for Tpl2 and highlight the therapeutic potential of blocking the endothelial-specific Tpl2 pathway in chronic inflammatory and metastatic diseases.

Increased vascular permeability and leakage are hallmarks of several pathologies and determine disease progression and severity by facilitating inflammatory / metastatic cell infiltration. Using tissue-specific genetic ablation in endothelial cells, we have investigated in vivo the role of Tpl2, a MAP3 kinase with pleiotropic effects in inflammation and cancer. In response to pro-inflammatory stimuli, endothelial Tpl2 deletion alters Tight Junction (TJ) claudin-5 protein expression and attenuates the increase in vascular permeability, inflammatory cell infiltration and accumulation of plasma proteins. This results in significantly attenuated disease scores in Experimental Autoimmune Encephalomyelitis and significantly less tumor nodules in a haematogenic lung cancer metastasis model. Accordingly, pharmacologic inhibition of Tpl2 or siRNA-mediated Tpl2 knockdown recapitulates our findings and reduces lung metastatic tumor invasions. These results establish a novel endothelial-specific role for Tpl2 in the regulation of TJ-mediated endothelial permeability and highlight the therapeutic potential of Tpl2 blockade in chronic inflammatory and metastatic diseases.

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder with no effective treatment to date. Despite its multi-factorial aetiology, oxidative stress is hypothesized to be one of the key pathogenic mechanisms. It is thus proposed that manipulation of the expression of antioxidant genes that are downregulated in the presence of mutant SOD1 may serve as a therapeutic strategy for motor neuronal protection. Lentiviral vectors expressing either PRDX3 or NRF2 genes were tested in the motor neuronal-like NSC34 cell line, and in the ALS tissue culture model, NSC34 cells expressing the human SOD1(G93A) mutation. The NSC34 SOD1(G93A) cells overexpressing either PRDX3 or NRF2 showed a significant decrease in endogenous oxidation stress levels by 40 and 50% respectively compared with controls, whereas cell survival was increased by 30% in both cases. The neuroprotective potential of those two genes was further investigated in vivo in the SOD1(G93A) ALS mouse model, by administering intramuscular injections of adenoassociated virus serotype 6 (AAV6) expressing either of the target genes at a presymptomatic stage. Despite the absence of a significant effect in survival, disease onset or progression, which can be explained by the inefficient viral delivery, the promising in vitro data suggest that a more widespread CNS delivery is needed.

Summary Coupled modelling of surface and subsurface systems is a valuable tool for quantifying surface water–groundwater interactions. In the present paper, the 3-D non-steady state Navier–Stokes equations, after Reynolds averaging and with the assumption of a hydrostatic pressure distribution, are for the first time coupled to the 3-D saturated groundwater flow equations in an Integrated suRface watEr–grouNdwater modEl (IRENE). A finite-difference method is used for the solution of the governing equations of IRENE. A semi-implicit scheme is used for the discretisation of the surface water flow equations and a fully implicit scheme for the discretisation of the groundwater flow equations. The two sets of equations are coupled at the common interface of the surface water and groundwater bodies, where water exchange takes place, using Darcy’s law. A new approach is proposed for the solution of the coupled surface water and groundwater equations in a simultaneous manner, in such a fashion that gives computational efficiency at low computational cost. IRENE is verified against three analytical solutions of surface water–groundwater interaction, which are chosen so that different components of the model can be tested. The model closely reproduces the results of the analytical solutions and can therefore be used for analysing and predicting surface water–groundwater interactions in real-world cases.

The objective of this chapter is the analysis of the three major components of drought assessment and management in Greece. First, the legal framework and the structure of services related to the water management are presented. Second, drought characterisation is applied for two river basins, Nestos and Mornos, and thresholds for drought management are defined. A new meteorological drought index, the Reconnaissance Drought Index (RDI), similar to the well-known Standardised Precipitation Index (SPI), is introduced. Finally, the operational component for drought management is analysed. This component consists of the formulation of a preparedness master plan and the adoption of proactive and reactive actions.

Gene therapy approaches to treat inherited and acquired disorders offer many unique advantages over conventional therapeutic approaches. For neurodegenerative diseases, gene therapy is particularly attractive due to the restricted bioavailability of conventional therapeutic substances to the affected structures of the brain and progressive nature of these diseases. With the development of lentiviral vector systems, many issues have been addressed and new delivery routes to the nervous system have been identified. Lentiviral vectors can efficiently deliver genes to postmitotic neuronal cell types offering long-term expression, can be generated in high titers, and do not give immunological complications. Various animal studies have demonstrated the effectiveness of these vectors to deliver therapeutic genes into the nervous system, as well as to model human diseases. This chapter will describe the basic features of lentiviral vectors, the progress, and their applications as a therapeutic strategy to treat diseases such as amyotrophic lateral sclerosis, spinal muscular atrophy, Parkinson's disease, and Huntington's disease.

The process of allelic exclusion ensures that each B cell expresses a B-cell receptor encoded by only one of its Ig heavy (IgH) and light (IgL) chain alleles. Although its precise mechanism is unknown, recruitment of the nonfunctional IgH allele to centromeric heterochromatin correlates with the establishment of allelic exclusion. Similarly, recruitment in activated splenic B cells correlates with cell division. In the latter, the recruited IgH allele was reported to be transcriptionally silent. However, it is not known whether monoallelic recruitment during establishment of allelic exclusion correlates with transcriptional silencing. To investigate this, we assessed the transcriptional status of both IgH alleles in single primary cells over the course of B-cell development, using RNA fluorescence in situ hybridization. Before allelic exclusion both alleles are transcribed. Thereafter, in pre-BII and subsequent developmental stages both functional and nonfunctional VDJ- and DJ-transcription is observed. Thus, after the establishment of IgH allelic exclusion, monoallelic recruitment to heterochromatin does not silence VDJ- or DJ-transcription, but serves another purpose.

In this experimental study, measurements concerning uniform flow in open channels, with semicircular cross sections and smooth or rough boundaries, are presented, analysed and discussed. Based on local velocity and boundary shear stress measurements, an effort is made to interpret the momentum and energy distribution, the internal boundary shear force and discharge distributions, the maximum boundary shear stress distributions as well as the Manning's n and friction factor's f variation, obtained for various groups of smooth or rough open channels used herein.

STAT5 interacts with other factors to control transcription, and the mechanism of regulation is of interest as constitutive active STAT5 has been reported in malignancies. Here, LSD1 and HDAC3 were identified as novel STAT5a interacting partners in pro-B cells. Characterization of STAT5a, LSD1 and HDAC3 target genes by ChIP-seq and RNA-seq revealed gene subsets regulated by independent or combined action of the factors and LSD1/HDAC3 to play dual role in their activation or repression. Genes bound by STAT5a alone or in combination with weakly associated LSD1 or HDAC3 were enriched for the canonical STAT5a GAS motif, and such binding induced activation or repression. Strong STAT5 binding was seen more frequently in intergenic regions, which might function as distal enhancer elements. Groups of genes bound weaker by STAT5a and stronger by LSD1/HDAC3 showed an absence of the GAS motif, and were differentially regulated based on their genomic binding localization and binding affinities. These genes exhibited increased binding frequency in promoters, and in conjunction with the absence of GAS sites, the data indicate a requirement for stabilization by additional factors, which might recruit LSD1/HDAC3. Our study describes an interaction network of STAT5a/LSD1/HDAC3 and a dual function of LSD1/HDAC3 on STAT5-dependent transcription, defined by protein–protein interactions, genomic binding localization/affinity and motifs.