Seasonal, spatial and inter-annual variations of trace metals in mussels from the Adriatic sea: a regional gradient for arsenic and implications for monitoring the impact of off-shore activities

Mussels are widely used as bioindicator organisms for monitoring chemical pollutants including trace metals. These elements are natural constituents in the marine environment and their basal concentrations in the organisms can be influenced by several environmental and biological factors. The aim of this work was to extend our knowledge on the natural variability of trace metals in mussels tissues, focusing on seasonal and inter-annual fluctuations in a coastal reference site of the Adriatic coast (Portonovo); a total of 39 samplings were performed during 5 years, providing an extended data-set for tissue levels of As, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V and Zn. Concentrations of trace metals in mussels tissues revealed marked seasonal fluctuations with significant differences between various sampling years. Such fluctuations appeared mostly related to phytoplanctonic blooms and especially to reproductive cycle which exhibited a certain inter-annual shift of the gametogenesis period. Lower concentrations were measured in summer months for the majority of elements while a different seasonal cycle was observed for arsenic, not correlated with gonadic development, neither with other elements. Chemical speciation of arsenic was characterized to distinguish compounds of natural origin from those potentially reflecting an anthropogenic impact. Arsenobetaine and arsenocholine were always the predominant forms (up to 85% of total arsenic), while a significant increase of dimethylarsine and trimethylarsine oxide in spring (24% of total arsenic) might reflect the effect of phytoplanctonic bloom on both geochemistry and trophic transfer of this element. A significant inter-annual variability was observed for both the seasonal cycle and the range of values measured for all the elements, with particularly marked differences for arsenic, ranging from less than 10 to more than 40 microg/g in summer periods of different years. Data obtained on reference mussels were used to assess the impact of 41 off-shore platforms distributed along 5 nautical districts in the Northern and Central Adriatic Sea. Organisms sampled on these structures from 2001 to 2005 exhibited a certain enrichment of cadmium and zinc, probably associated to the use of anodic electrodes. Marked annual and geographical variations were measured for concentrations of arsenic in mussels of different platforms. However, the comparison with results of Portonovo, allowed to exclude the anthropogenic impact of exploitation activities and revealed a natural regional gradient of arsenic levels in mussels tissues associated to the changing influence of the Po river runoff on seawater salinity. In particular the higher concentrations measured in organisms sampled from platforms in the Central compared to Northern Adriatic confirmed a significant relationship between salinity and arsenic bioaccumulation, consistent with a role of arsenobetaine as an acquired osmolyte for mussels. The overall results confirmed the importance of natural variability when assessing the potential impact of anthropogenic activities.     

Proposal for standardized prenatal ultrasound assessment of the fetus with congenital diaphragmatic hernia by the European reference network on rare inherited and congenital anomalies (ERNICA)

Congenital diaphragmatic hernia is a rare disease associated with high mortality and morbidity. Antenatal ultrasound screening identifies more than 70% of cases, providing the opportunity for in utero referral to a tertiary care center for expert assessment and perinatal management. Additional genetic and morphologic assessment may be used to rule out associated anomalies. In isolated cases, the outcome may be predicted prenatally by medical imaging. The combination of lung size and liver herniation is a widely accepted method to stratify fetuses into groups with an increasing degree of pulmonary hypoplasia and corresponding mortality rates. Ultrasound measurement of the observed to expected lung-to-head ratio (o/e LHR) is most widely used. The o/e LHR is an independent predictor of survival and short-term morbidity. Finally, evaluation of stomach position has recently been introduced as an indirect method to estimate severity of the disease in left-sided defects, as it has been shown to correlate with the proportion of intrathoracic liver. Herein, we propose a protocol for the standardized ultrasound assessment of fetuses with isolated CDH and individualized prediction of neonatal outcome.     

Estimating disease risk at the whole plant level with General Circulation Models

General Circulation Models (GCMs) have been developed to assess the impacts of potential global climate change. However, these models do not provide specific weather information at the whole-plant level and thus provide only very gross estimates of conditions that affect plant and disease development. Also, climatic change may increase the frequency of extreme events that influence plant production more than changes in daily or monthly averages. One solution is a simulation approach that can scale weather information from the global down to the plant scale. Over the last 4 years, we have been developing methods to hierarchically define current and forecast weather conditions down to the whole-plant level based on nested high-resolution atmospheric (mesoscale) numerical models. Two hierarchical mesoscale model approaches were tested to downscale weather data in a vineyard. The first, known as the Localized Mesoscale Forecast System (LMFS) uses surface databases to 'localize' mesoscale output. The second, known as the Canopy-Mesoscale Forecast System (CMFS), uses a boundary layer model to downscale mesoscale output. To illustrate the utility of this approach we focused on surface wetness duration (SWD), a variable with high spatial and temporal variability. SWD is also a critical variable for prediction of plant disease. Simulations of SWD with on-site input data were compared to those derived from the mesoscale models and to on-site sensors. Forecasts of atmospheric variables by the two systems were compared to on-site observations. Success in this effort leads us to extend this method to GCMs where factors such as temperature, rainfall, relative humidity, and surface wetness can be estimated within plant and crop canopies. We explore the implications of this work on evaluating the assessment of climate change on the risk of plant disease development.     

Quantitative Real-Time PCR and Digital PCR to Evaluate Residual Quantity of HAV in Experimentally Depurated Mussels

Food and Environmental Virology - Kinetics of hepatitis A virus (HAV) accumulation and depuration from mussels (Mytilus galloprovincialis) was studied in an experimental depuration system....     

Study of the severity of hybrid mixture explosions and comparison to pure dust-air and vapour-air explosions

The explosion behaviour of heterogeneous/homogeneous fuel-air (hybrid) mixtures is here analysed and compared to the explosion features of heterogeneous fuel-air and homogeneous fuel-air mixtures separately.Experiments are performed to measure the pressure history, deflagration index and flammability limits of nicotinic acid/acetone-air mixtures in a standard 20 L Siwek bomb adapted to vapour-air mixtures. Literature data are also used for comparison.The explosion tests performed on gas-air mixtures in the same conditions as explosion tests of dust-air mixtures, show that the increase in explosion severity of dust/gas-air mixtures has to be addressed to the role of initial level of turbulence prior to ignition.At a fixed value of the equivalence ratio, by substituting the dust to the flammable gas in a dust/gas-air mixture the explosion severity decreases. Furthermore, the most severe conditions of dust-gas/air mixtures is found during explosion of gas-air mixture at stoichiometric concentration.     

Third trimester ultrasound diagnosis of intestinal atresia following clinical evidence of polyhydramnios

Five cases of intestinal atresia were diagnosed using real-time ultrasonography following clinical evidence of polyhydramnios. No correlation was noted between ultrasound findings and the severity of the lesions. Two of the five babies died at 35 and 77 days respectively. Prematurity and presence of other abnormalities were factors in the deaths.