Risk analysis of marine activities in the Belgian part of the North Sea (RAMA): final report

RAMA is a 2-year project (04/2004 - 04/2006) executed by two Belgian partners, Ecolas NV (Environmental Consultancy Agency) and the Maritime Institute (University of Ghent), and financed by the SPSD II research program, specific actions, of the Belgian Science Policy (BELPSO). RAMA aims to assess the environmental risks of spills by commercial shipping activities on the Belgian Part of the North Sea. Shipping patterns, transports of dangerous goods, probability of risks and the potential impact of spill incidents (oil & hazardous and noxious substances) will be assessed. The risk analysis within this project studies both the chances of a spill accident happening and the environmental impacts in case of an accident. The valorisation of the RAMA project will result in a thorough analysis of the current status of the shipping at the North Sea in relation to the issue of safety. The scope of the project will however go beyond the mere result of a fundamental risk analysis of the commercial shipping at the North Sea. It is also aiming at the formulation of recommendations to improve the safety level for the environment and at an optimization of response in the framework of the Belgian "North Sea Disaster Plan"

STAT3-dependent VEGF production from keratinocytes abrogates dendritic cell activation and migration by arsenic: a plausible regional mechanism of immunosuppression in arsenical cancers

[[abstract]]Arsenic remains an important environmental hazard that causes several human cancers. Arsenic-induced Bowen’s disease (As-BD), a skin carcinoma in situ, is the most common arsenical cancer. While great strides have been made in our understanding of arsenic carcinogenesis, how host immunity contributes to this process remains unknown. Patients with As-BD have an impaired contact hypersensitivity response. Although impaired T cell activation has been well-documented in arsenical cancers, how dendritic cell (DC), the key cell regulating innate immunity, regulates the immune response in arsenical cancers remains unclear. Using myeloid derived DC (MDDC) from patients with As-BD and normal controls as well as bone marrow derived DC (BMDC) from mice fed with or without arsenic, we measured the migration of DC. As-BD patients showed an impaired CCL21-mediated MDDC migration in vitro. Arsenic-fed mice had defective DC migration towards popliteal lymph nodes when injected with allogenic BMDCs via foot pad. Using skin from As-BD and normal controls, we found an increased expression of STAT3, a transcriptional factor contributing to impaired DC activation. Arsenic induced STAT3 activation and the production of VEGF in keratinocytes. The increase in VEGF was blocked by inhibiting STAT3 with RNA interference or pharmaceutically with JSI-124. While VEGF by itself minimally induced the expression of CD86 and MHC-II in MDDC, arsenic induced-MDDC activation was abolished by VEGF pretreatment. We concluded that the STAT3-VEGF axis in keratinocytes inhibits DC migration in the microenvironment of As-BD, indicating that cellular interactions play an important role in regulating the disease course of arsenical cancers

Macroevolution of gastric Helicobacter species unveils interspecies admixture and time of divergence

Since the discovery of the human pathogen Helicobacter pylori, various other Helicobacter species have been identified in the stomach of domesticated and wild mammals. To better understand the evolutionary history of these ecologically similar but genetically distinct species, we analyzed 108 gastric Helicobacter genomes and included 54 enterohepatic Helicobacter genomes for comparison purposes. An admixture analysis supported the presence of an ecological barrier, preventing the genetic exchange between the gastric and enterohepatic Helicobacter species, and unraveled many gene flow events within and across species residing in the stomach. As pets can be colonized by multiple gastric Helicobacter species, the genetic exchange between the canine and feline strains was evident, with H. heilmannii and H. bizzozeronii showing the highest interspecies recombination. An admixture between H. pylori (in particular, the ancestral African strains), H. acinonychis from wild felines and H. cetorum from marine mammals was also identified. Because these latter species do not share the same host, this phenomenon is most likely a remaining signal of shared ancestry. A reconstruction of the time of divergence of the gastric Helicobacter spp. revealed that the domestic animal-related Helicobacter species evolved in parallel with H. pylori and its two closest relatives (H. acinonychis and H. cetonum), rather than together