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The in vivo and in vitro pathogenic actions of whole cells and extracellular products of Vibrio alginolyticus for cultured gilt-head sea bream were studied. The strains were able to fasten to the skin, gills and intestinal mucus of sea bream and to cultured cells of a chinook salmon embryo cell line. The extracellular products were observed to destroy sea bream mucus and tissues. V. alginolyticus was cytotoxic for fish cell lines and deadly for sea bream.

The adhesive kinetics of Vibrio strains isolated from diseased gil-head sea bream to superficial skin mucus was investigated by adhesive assay and spectroscopy. Data indicated saturation kinetics for V. anguillarum-like strains, whereas V. alginolyticus showed a proportional adsorption kinetics. Mucus did not have an effect on the adhesive ability of the pathogenic microorganisms, suggesting that there is no relationship between adhesive capability for skin mucus and virulence.

Research was conducted to examine the chemotaxis of pathogenic Vibrio strains towards mucus surfaces of gilt-head sea bream Sparus aurata L and to stuy the influence of salinity and temperature on the process. Twenty-two strains of Vibrio anguillarum and Vibrio alginolyticus were isolated from diseased gilt-head sea bream and their abilities to assay were determined following the preparation of raw skin, gill and intestinal mucus. Results indicate that the mucus surfaces are potential portal entries in the fish for V anguillarum and V alginolyticus.

The Rydberg spectrum of Na2 has been shown previously to alternate when increasing energy between ‘‘stroboscopic fringes’’ which correspond to a well known separable Hund’s coupling case (a), and a complex, unidentifiable intermediate coupling. We use this system as a prototypic example to test some current ideas on the correspondence between classical chaos and properties of quantum spectra. We first determine the phase space structure and transition to chaos in classical mechanics. We then determine the change in line intensities and level spacing statistics in quantum mechanics. We show that this system has the expected behavior in the semiclassical limit in the presence of classical chaos, except for a peculiarity in level spacing statistics, but that this behavior is not a signature of chaos, since the same system shows similar behavior for some values of the parameters which correspond to a nonchaotic situation in classical mechanics. We discuss also some problems related to the nonvalidity of the semiclassical limit. [ABSTRACT FROM AUTHOR]

The aetiological agents of the abdominal swelling affecting farmed larvae of gilt-head seabream, Sparus aurata L., were studied. Four Vibrio strains were isolated from larvae of S. aurata affected by this disease, and all strains reproduced the disease in healthy larvae under controlled infection experiments, producing a significant increase of the mortality rates compared to the control (non-inoculated larvae). Several enzymatic properties, which can act as virulence factors, were demonstrated both in the extracellular products (ECPs) and in live cells of the strains tested. Histopathological examinations of the infected fish larvae revealed important changes of the anterior intestine and liver characterized by a marked hyperthrophy of the intestinal epithelium and hepatocytes, and by a separation of the mucosal and submucosal layers in the digestive tube. These histological alterations were associated with the constant presence of cocobacillar bacteria in the anterior intestine and in the liver. However, the precise pathogenic mechanisms of the strains tested have not been completely elucidated yet. [ABSTRACT FROM AUTHOR]

Similar populations have been observed between the A and X states of the CN radical, formed in the C+N2O chemical reaction. Relative vibrational populations were measured by laser-induced fluorescence (X state) and chemiluminescence (A state). The electronic branching ratio was then obtained by assuming a Boltzmann equilibrium between the v‘=4–6 and v’=1–4 levels of the X and A states. This assumption was checked by absolute calibration of the number densities of both states. About 1/3 of the radicals were found in the A state. [ABSTRACT FROM AUTHOR]

Presents a study to measure bacterial chemotaxis of pathogenic Vibrio strains towards mucus surfaces of gilt-head sea bream (Sparus aurata L.) Methodology used to conduct study; Indication of findings; Discussion on results.

Despite increasing knowledge about small extracellular vesicle (sEV) composition and functions in cell-cell communication, the mechanism behind their biogenesis remains unclear. Here, we reveal for the first time that sEV biogenesis and release into the microenvironment are tightly connected with another important organelle, Lipid Droplets (LDs). The correlation was observed in several human cancer cell lines as well as patient-derived colorectal cancer stem cells (CR-CSCs). Our results demonstrated that external stimuli such as radiation, pH, hypoxia or lipid-interfering drugs, known to affect the number of LDs/cell, similarly influenced sEV secretion. Importantly, through multiple omics data, at both mRNA and protein levels, we revealed RAB5C as a potential important molecular player behind this organelle connection. Altogether, the potential to fine-tune sEV biogenesis by targeting LDs could significantly impact the amount, cargos and properties of these sEVs, opening new clinical perspectives., Competing Interests: All authors declare no conflict of interest., (© 2024 The Author(s). Journal of Extracellular Biology published by Wiley Periodicals LLC on behalf of International Society for Extracellular Vesicles.)