Polyunsaturated Aldehydes Profile in the Diatom Cyclotella cryptica Is Sensitive to Changes in Its Phycosphere Bacterial Assemblages.

Diatoms are responsible for the fixation of ca. 20% of the global CO2 and live associated with bacteria that utilize the organic substances produced by them. Current research trends in marine microbial ecology show which diatom and bacteria interact mediated through the production and exchange of infochemicals. Polyunsaturated aldehydes (PUA) are organic molecules released by diatoms that are considered to have infochemical properties. In this work, we investigated the possible role of PUA as a mediator in diatom-bacteria interactions. To this end, we compare the PUA profile of a newly isolated oceanic PUA producer diatom, Cyclotella cryptica, co-cultured with and without associated bacteria at two phosphate availability conditions. We found that the PUA profile of C. cryptica cultured axenically was different than its profile when it was co-cultured with autochthonous (naturally associated) and non-autochthonous bacteria (unnaturally inoculated). We also observed that bacterial presence significantly enhanced diatom growth and that C. cryptica modulated the percentage of released PUA in response to the presence of bacteria, also depending on the consortium type. Based on our results, we propose that this diatom could use released PUA as a specific organic matter sign to attract beneficial bacteria for constructing its own phycosphere, for more beneficial growth.

Evaluation of the hospital care quality perceived by patients with immune-mediated inflammatory diseases from the pharmacy service. SACVINFA study.

WHAT IS KNOWN AND OBJECTIVE: Immune-mediated inflammatory diseases (IMIDs) are a group of chronic and highly disabling diseases. The objective is to evaluate the satisfaction with the health care received by patients with the most prevalent IMIDs in Spain: inflammatory bowel disease (IBD), psoriasis (Ps) psoriatic arthritis (PsA), rheumatoid arthritis (RA) and spondyloarthropathies (SpAs), and to determine the factors that influence patient satisfaction. METHODS: This was an observational, cross-sectional, multicentre study in a real-world evidence context conducted in the Pharmacy Service in four hospital centres of the Community of Madrid that belong to the National Health System. The study included adult patients diagnosed with an IMID who had attended the Pharmacy Service at least three times. The patients were grouped according to the main IMID. Health care satisfaction was evaluated using the chronic patient experience assessment (IEXPAC) questionnaire. The responses to IEXPAC are grouped into three factors: productive interactions, new relational model and patient self-management, with a total score from 0 (worst) to 10 (best experience). Health-related quality of life (HRQoL) was also evaluated using the EQ-5D-5L questionnaire, and pharmacological adherence was evaluated through the Morisky-Green test. RESULTS AND DISCUSSION: A total of 578 patients were analysed (IBD = 25.3%; Ps = 19.7%; SpAs = 18.7%; RA = 18.5%; PsA = 17.8%). The mean age (SD) was 49.8 (12.3) years and 50.7% were male. The average score (SD) for the total IEXPAC sample was 6.6 (1.9). RA was the IMID with the lowest score, at 5.83 (2.0), significantly lower than the scores of Ps (SD) [7.01 (1.7); p = 0.003], IBD [6.83 (1, 9); p = 0.012] and SpAs [6.80 (1.6); p = 0.001]. Productive interactions (SD) [8.5 (1.8)] and patient self-management (SD) [7.3 (2.3)] were the factors with the highest scores, and the new relational model had the lowest score (SD) [3.2 (2.7)]. Male gender, a longer time interval between medication administrations and a higher HRQoL were correlated with better patient satisfaction. Current biological therapy (according to the Anatomical Chemical classification system) also had a significant influence; patients treated with tumour necrosis factor inhibitors and interleukin inhibitors showed greater satisfaction than those treated with selective immunosuppressants. WHAT IS NEW AND CONCLUSION: The IEXPAC results show high general satisfaction with care quality reported by patients with IMIDs treated in the Pharmacy Service. However, there are areas of improvement in care quality specially health professional-patient communication, such as increasing access to information, and promoting and facilitating relationships with patients in similar conditions.

Microalgae cultivation in urban wastewater: Coelastrum cf. pseudomicroporum as a novel carotenoid source and a potential microalgae harvesting tool.

The aim of this work was to study the optimal growth and high value-added production of the microalgae Coelastrum cf. pseudomicroporum Korshikov cultivated in urban wastewater. It was observed that C. cf. pseudomicroporum grew ideally in this medium, acting as an efficient nutrient starver. Additionally, the obtained biomass increased carotenoid cell content after saltwater stress. The effects of light intensity and salt stress on its growth rate were analysed. The results showed that this alga can grow very fast using wastewater as culture medium, reaching maximum growth rates of 1.61±0.05day-1, and tolerating strong irradiances. It was also found that under salt-stress this species could accumulate carotenoids (range 1.73-91.2pgcell-1). Moreover, a good harvesting efficiency (96.84%) was observed using Coelastrum exudates as bioflocculant of Scenedesmus sp., so Coelastrum exudates could act as a potential bioflocculant for other species.

Plastic accumulation in the Mediterranean sea.

Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region.

Plastic debris in the open ocean.

There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density. However, the global load of plastic on the open ocean surface was estimated to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to determine the nature and significance of the impacts of plastic pollution in the ocean.

Potential effects of climate change on the water level, flora and macro-fauna of a large neotropical wetland.

Possible consequences of climate change in one of the world's largest wetlands (Ibera, Argentina) were analysed using a multi-scale approach. Climate projections coupled to hydrological models were used to analyse variability in wetland water level throughout the current century. Two potential scenarios of greenhouse gas emissions were explored, both resulting in an increase in the inter-annual fluctuations of the water level. In the scenario with higher emissions, projections also showed a long-term negative trend in water-level. To explore the possible response of biota to such water-level changes, species-area relationships of flora and aerial censuses of macro-fauna were analysed during an extraordinary dry period. Plant species richness at the basin scale was found to be highly resistant to hydrological changes, as the large dimension of the wetland acts to buffer against the water-level variations. However, local diversity decreased significantly with low water levels, leading to the loss of ecosystem resilience to additional stressors. The analysis of macro-fauna populations suggested that wetland provides refuge, in low water periods, for the animals with high dispersal ability (aquatic and migratory birds). On the contrary, the abundance of animals with low dispersal ability (mainly herbivorous species) was negatively impacted in low water periods, probably because they are required to search for alternative resources beyond the wetland borders. This period of resource scarcity was also related to increased mortality of large mammals (e.g. marsh deer) around water bodies with high anthropogenic enrichment and cyanobacteria dominance. The synergy between recurrent climatic fluctuations and additional stressors (i.e. biological invasions, eutrophication) presents an important challenge to the conservation of neotropical wetlands in the coming decades.

Basin-scale control on the phytoplankton biomass in Lake Victoria, Africa.

The relative bio-optical variability within Lake Victoria was analyzed through the spatio-temporal decomposition of a 1997-2004 dataset of remotely-sensed reflectance ratios in the visible spectral range. Results show a regular seasonal pattern with a phase shift (around 2 months) between the south and north parts of the lake. Interannual trends suggested a teleconnection between the lake dynamics and El-Niño phenomena. Both seasonal and interannual patterns were associated to conditions of light limitation for phytoplankton growth and basin-scale hydrodynamics on phytoplankton access to light. Phytoplankton blooms developed during the periods of lake surface warming and water column stability. The temporal shift apparent in the bio-optical seasonal cycles was related to the differential cooling of the lake surface by southeastern monsoon winds. North-south differences in the exposure to trade winds are supported by the orography of the Eastern Great Rift Valley. The result is that surface layer warming begins in the northern part of the lake while the formation of cool and dense water continues in the southern part. The resulting buoyancy field is sufficient to induce a lake-wide convective circulation and the tilting of the isotherms along the north-south axis. Once surface warming spreads over the whole lake, the phytoplankton bloom dynamics are subjected to the internal seiche derived from the relaxation of thermocline tilting. In 1997-98, El-Niño phenomenon weakened the monsoon wind flow which led to an increase in water column stability and a higher phytoplankton optical signal throughout the lake. This suggests that phytoplankton response to expected climate scenarios will be opposite to that proposed for nutrient-limited great lakes. The present analysis of remotely-sensed bio-optical properties in combination with environmental data provides a novel basin-scale framework for research and management strategies in Lake Victoria.