Identification and whole-genome sequencing analysis of Vibrio vulnificus strains causing pearl gentian grouper disease in China.

Vibrio vulnificus is a pathogenic bacterium that causes disease in marine fish, affecting fish farming and human health worldwide. In May 2021, in the Bohai Bay region, a disease broke out in commercially farmed pearl gentian grouper (♀Epinephelus fuscoguttatus × â™‚Epinephelus lanceolatus), causing huge economic losses. The diseased fish had skin lesions, water accumulation in their abdomens, and showed tissue and organ damage. V. vulnificus biotype 2 has been reported in eels and other marine fish, but it is less reported in pearl gentian grouper. In this study, the pathogenic strain isolated from diseased fish was identified as V. vulnificus EPL 0201 biotype 2 on the basis of physiological and biochemical characteristics and the results of 16S rRNA gene and gyrB sequencing, virulence gene detection, and recursive infection experiments. To gain a comprehensive understanding of the pathogenicity and drug resistance of this strain, whole-genome sequencing was performed. Whole-genome analysis showed that the gene map of this strain was complete. The Virulence Factor Database annotation results showed that this strain had the key virulence factor genes vvhA and rtxA, which cause host disease. In addition, this strain had genes conferring resistance against cephalosporins, aminoglycosides, tetracyclines, and sulfonamides. Antimicrobial susceptibility testing confirmed the presence of these resistance genes identified in the genome. The results of this study show that V. vulnificus EPL 0201 biotype 2 is a multi-drug resistant strain with high pathogenicity.

Attachment style predicts cooperation in intuitive but not deliberative response in one-shot public goods game.

Cooperation is an important prosocial behaviour that is of great significance to individuals and society. The social heuristics hypothesis (SHH) systematically explains how cooperation is interactively affected by intuitive and deliberative processes. On the one hand, the intuitive process can be either cooperative or selfish, which is determined by previous experience. On the other hand, the deliberative process could support either a cooperative decision or a selfish decision, depending on which strategy could maximise the current payoff. This research aims to investigate the mechanism of cooperation. Attachment style was selected as a proxy for previous experience to examine whether and how previous life experience shapes intuitive response. Time constraint (Studies 1 and 2) and cognitive load (Study 3) were manipulated to dissociate the intuitive and deliberative processes. In addition, cooperation was assessed by adopting one-shot public goods games. Results showed that attachment avoidance (Studies 1, 2, and 3) and attachment anxiety (Study 3) significantly predicted cooperation in the intuition condition, whereas these associations were insignificant in the deliberation condition (Studies 1, 2, and 3). These findings provide further support for the SHH and shed new light on the mechanism of cooperation.

Eco-toxicology effect on Moina mongolica Daday exposed to Cd2+, Pb2+, and Hg2+ by the food chain.

As one of the most important contaminants, heavy metals can seriously influence human health via the food chain. In this study, the eco-toxicological effects of Cd2+, Pb2+, and Hg2+ on Moina mongolica Daday were investigated by feeding them Chlorella sp. that contained heavy metals. The relative body lengths of the M. mongolica changed rapidly, peaking at 2 days for Hg2+, 6 days for Cd2+, and 8 days for Pb2+. Moreover, grazing and clearance rates of the experimental group were apparently lower than those of the control group after immersion in heavy metals. Additionally, Cd2+ and Pd2+ in the food significantly influenced the mean lifespan of M. mongolica of the P and F1 generations. Egg production per brood was also significantly impacted by Cd2+ and Pb2+ in the food in generation P. Interestingly, Pb2+ was the only metal that significantly influenced the reproduction times of F2, while the reproductive times were significantly influenced by Cd2+ for generation P. Moreover, Cd2+, Pb2+, and Hg2+ in the food significantly influenced the fecundity of generation P. Evaluation of the population growth parameters of M. mongolica revealed that the intrinsic rate of increase, net reproduction rate, and finite rate of increase were significantly influenced by Cd2+, Pb2+, and Hg2+ in the food in generation P. Additionally, Hg2+ slightly impacted generation time for generation P. Finally, the acute toxicity toward M. mongolica was Hg2+ > Cd2+ > Pb2+. Overall, heavy metals in the food were likely to influence the growth, survival, and population growth of M. mongolica through the food chain.