Genetic structure of gilthead seabream, Sparus aurata, in the Central Mediterranean Sea

Abstract The gilthead seabream, Sparus aurata, represents an important economic resource for Mediterranean aquaculture. In spite of its wide geographic distribution and economic importance, only recently studies have been carried out on the genetic composition of natural populations, which have revealed a picture of a heterogeneous degree of genetic differentiation among S. aurata populations. In this study an allozyme analysis of samples from six different collecting sites along the Italian and Croatian coasts was carried out, covering an area in the Central Mediterranean sea that has yet to be investigated through gene-enzyme systems. Data on 26 gene loci, 10 of which are polymorphic, indicate a slight but significant genetic structure (FST = 0.0167) of the species. A hierarchical analysis of population subdivision made it possible to identify three different assemblages found in the Adriatic Sea, Tyrrhenian Sea and Sardinian Channel, though an isolation by distance model can be rejected. The results are discussed in the light of previous literature and taking conservation into consideration

Cytogenetic studies in Sparus auratus

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molecular and morphological identification of an uncommon centrolophid fish

AbstractThe use of both morphological and molecular methods has allowed a fast and reliable species assignment of a fish that local fishermen with over thirty years of experience had never seen before. The identified species, Schedophilus medusophagus, is rare along Italian coasts, and this is the first documented record in the Central Tyrrhenian Sea for over 35 years. Its abundance should be evaluated on a continuous basis, as it might reflect biological consequences of environmental and climatic change. The mitochondrial sequences obtained in this study constitute a useful molecular tag for future research and may contribute to the phylogenetic debate on the status of the genus Schedophilus, of which S. medusophagus is the type species. Based on the existing literature, these preliminary molecular data support the hypothesis that the genus is not monophyletic

Differential expression patterns of purinergic ectoenzymes and the antioxidative role of IL-6 in hospitalized COVID-19 patient recovery

IntroductionWe have acquired significant knowledge regarding the pathogenesis of severe acute respiratory syndrome caused by coronavirus 2 (SARS-CoV-2). However, the underlying mechanisms responsible for disease recovery still need to be fully understood.MethodsTo gain insights into critical immune markers involved in COVID-19 etiopathogenesis, we studied the evolution of the immune profile of peripheral blood samples from patients who had recovered from COVID-19 and compared them to subjects with severe acute respiratory illness but negative for SARS-CoV-2 detection (controls). In addition, linear and clustered correlations between different parameters were determined.ResultsThe data obtained revealed a significant reduction in the frequency of inflammatory monocytes (CD14+CD16+) at hospital discharge vs. admission. Remarkably, nitric oxide (NO) production by the monocyte compartment was significantly reduced at discharge. Furthermore, interleukin (IL)-6 plasma levels were negatively correlated with the frequency of NO+CD14+CD16+ monocytes at hospital admission. However, at the time of hospital release, circulating IL-6 directly correlated with the NO production rate by monocytes. In line with these observations, we found that concomitant with NO diminution, the level of nitrotyrosine (NT) on CD8 T-cells significantly diminished at the time of hospital release. Considering that purinergic signaling constitutes another regulatory system, we analyzed the kinetics of CD39 and CD73 ectoenzyme expression in CD8 T-cells. We found that the frequency of CD39+CD8+ T-cells significantly diminished while the percentage of CD73+ cells increased at hospital discharge. In vitro, IL-6 stimulation of PBMCs from COVID-19 patients diminished the NT levels on CD8 T-cells. A clear differential expression pattern of CD39 and CD73 was observed in the NT+ vs. NT-CD8+ T-cell populations.DiscussionThe results suggest that early after infection, IL-6 controls the production of NO, which regulates the levels of NT on CD8 T-cells modifying their effector functions. Intriguingly, in this cytotoxic cell population, the expression of purinergic ectoenzymes is tightly associated with the presence of nitrated surface molecules. Overall, the data obtained contribute to a better understanding of pathogenic mechanisms associated with COVID-19 outcomes