Water quality evaluation in Mediterranean Lagoons using the Multimetric Phytoplankton Index (MPI): study cases from Sardinia

1 - Water quality in four Sardinian lagoons (western Mediterranean Sea) was assessed using the Multimetric Phytoplankton Index (MPI), which is consistent with the EU Water Framework Directive. The index was developed using data on phytoplankton abundances, species structure and chlorophyll a concentrations in Venice Lagoon, Italy. 2 - The aim of this study was to test the MPI on a larger geographical scale and across a range of lagoon types. Therefore, it was applied to assess water quality in the Cabras, S’Ena Arrubia, Santa Giusta and Calich lagoons in Sardinia. These lagoons are all “choked”, but exhibit a range of sizes and morphometric features. They are directly affected by human activity within the lagoons themselves, such as fisheries, aquaculture and the construction of dams and canals, and are indirectly affected by anthropogenic activities in their catchments, including intensive agriculture, industrial activity and urban development. 3 - The data used in the present study were collected monthly over a period of 4 years (Calich, Santa Giusta and S’Ena Arrubia) to 7 years (Cabras). Samples were collected at three stations at each of the Cabras, Santa Giusta and Calich lagoons, and at two stations at the S’Ena Arrubia Lagoon, providing a total of 220 samples. 4 - The water quality in three of the four lagoons investigated (Cabras, S’Ena Arrubia and Calich) was classified as bad using the MPI. Among these three, water in Cabras Lagoon exhibited the worst condition. Water quality in Santa Giusta Lagoon was classified as poor using the MPI. 5 - Although we present preliminary results that require further verification, the index appears to be a useful tool for assessing the ecological status of typical Mediterranean lagoons

Bacterial and viral investigations combined with determination of phytoplankton and algal biotoxins in mussels and water from a Mediterranean coastal lagoon (Sardinia, Italy).

Calich Lagoon is a Mediterranean coastal lagoon located along the northwestern coast of Sardinia (Italy). The connection to marine and fresh water determines the high productivity of this coastal lagoon. Despite its great potential and the presence of natural beds of bivalve mollusks (Mytilus galloprovincialis), the lagoon has not yet been classified for shellfish production. In this study, through a multidisciplinary approach, the presence of several bacterial pathogens (Escherichia coli, Salmonella spp., and Vibrio spp.) and viral pathogens (hepatitis A virus and norovirus genogroups I and II) was evaluated from March 2017 to February 2018. In addition, phytoplankton composition in lagoon waters and associated algal biotoxins (paralytic and diarrhetic shellfish poisoning) in mussels were also monitored. The aim of this study was to provide useful data to improve knowledge about their seasonal presence and to assess the potential risk for public health, as well as to provide input for future conservation and management strategies. In mussels, Salmonella spp. were found in spring, along with E. coli, but Salmonella spp. were not found in autumn or winter, even though E. coli was detected in these seasons. Vibrio parahaemolyticus was found in autumn and winter, but not in spring. Norovirus genogroups I and II were found in winter samples. None of the bacteria were found in summer. Algal biotoxins have never been detected in mussel samples. Among potentially harmful phytoplankton, only Pseudo-nitzschia spp. were present, mainly in summer. The results showed that a possible bacterial and viral contamination, together with the presence of potentially toxic microalgae, is a real problem. Therefore, the development of natural resource management strategies is necessary to ensure the good quality of waters and guarantee the protection of consumers

Le Problematiche degli Harmful Algal Blooms (HABs) in Sardegna = Harmful Algal Blooms in Sardinia

Harmful Algal Blooms are events that produce damage to the environment and/or risk to the health of humans and aquatic life. A part of the responsible species acts through toxins whereas other no toxic species can grow to high biomass, causing different consequences. The different typologies of HABs is signalled also along Sardinian coast. Indications on specific events are reported

New evidence of pectenotoxins in farmed bivalve molluscs from Sardinia (Italy)

Several planktonic dinoflagellates can produce lipophilic phycotoxins that represent a significant threat to public health as well as to shellfish and fish farming. Poisoning related to some of these toxins is categorised as diarrhetic shellfish poisoning. We analysed 975 shellfish samples from Tortolì in the central-eastern region of Sardinia (Italy) from January 2016 to March 2020, to investigate the prevalence of different lipophilic marine biotoxins in mollusc bivalves. The results highlighted the predominant presence of toxins belonging to the okadaic acid group in all samples with toxin concentrations exceeding legal limits, and revealed the new occurrence of pectenotoxins in oysters and clams with a winter seasonality in recent years. The origin of shellfish toxicity was associated with the same Dinophysis species, mainly D. acuminata. Based on both these results and other precedents, monitoring and recording systems are strongly recommended

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

Spatial distribution and multiannual trends of potentially toxic microalgae in shellfish farms along the Sardinian coast (NW Mediterranean Sea)

In this study, the geographical distribution and multiannual trends of potentially toxic harmful algal species (HAS) were analysed at 18 mussel farms in Sardinia (Italy, North-Western Mediterranean Sea) using data derived from the Sardinian Regional Monitoring Programme (1988–2012). The results showed an increasing number of potentially toxic microalgae over the study period. Alexandrium catenella and Alexandrium minutum were the most harmful species detected. From 2002 to 2009, these species caused eight paralytic shellfish poisoning-positive events which temporarily stopped commercial trade of mussels. The statistical analysis indicated that some taxa exhibited temporal increasing trends in their abundance (e.g. Pseudo-nitzschia spp.), significant decrements (e.g. Dinophysis sp.), or both increasing and decreasing significant trends (e.g. A. minutum) at different sites, indicating the necessity of further in-depth studies, especially on certain taxa. Overall, the statistical elaboration of the long-term data provided useful signals for early detection of shellfish contamination by different potentially toxic HAS in defined sites. These signals can be used to develop best management practices