Identification of antiparkinsonian drugs in the 6-hydroxydopamine zebrafish model.

Parkinson's disease (PD) is known as a movement disorder due to characteristic motor features. Existing therapies for PD are only symptomatic, and their efficacy decreases as disease progresses. Zebrafish, a vertebrate in which parkinsonism has been modelled, offers unique features for the identification of molecules with antiparkinsonian properties.

Effects of exposure to PAHs on brain AChE in gilthead seabream, Sparus aurata L., under laboratory conditions.

The purpose of this research was to assess the effects of exposure to selected PAHs (phenanthrene, pyrene, and fluorene) on brain acetylcholinesterase (AChE) in juvenile gilthead seabream (Sparus aurata) in short term in vivo experiments. The measured brain AChE activity was within the same range (110-200 nmol min(-1) mg prot(-1)) in all the considered treatment conditions and in the control. The only statistically significant difference in AChE activity with respect to the control group was its induction in response to the lowest tested pyrene concentration in one of two replicated studies.

Synergistic effects of the membrane actions of cecropin-melittin antimicrobial hybrid peptide BP100.

BP100 (KKLFKKILKYL-NH(2)) is a short cecropin A-melittin hybrid peptide, obtained through a combinatorial chemistry approach, which is highly effective in inhibiting both the in vitro and in vivo growth of economically important plant pathogenic Gram-negatives. The intrinsic Tyr fluorescence of BP100 was taken advantage of to study the peptide's binding affinity and damaging effect on phospholipid bilayers modeling the bacterial and mammalian cytoplasmic membranes. In vitro cytotoxic effects of this peptide were also studied on mammalian fibroblast cells.

Biochemical response in gilthead seabream (Sparus aurata) to in vivo exposure to a mix of selected PAHs.

In our previous studies we assessed the biochemical response of juvenile seabream to the exposure to three selected polycyclic aromatic hydrocarbons (PAHs) (phenanthrene, pyrene and fluorene) in short-term laboratory experiments. Since in the analyses conducted in the field it is much more natural to expect the presence of multiple contaminants at the same time, the objective of this study was to analyse the reaction of seabream to the exposure to a mix of the three PAHs tested previously. The proportions of the individual components in the PAH mix used in our experiments were constant and determined on the basis of the concentration addition concept.

The joint effect of polycyclic aromatic hydrocarbons on fish behavior.

Polycyclic aromatic hydrocarbons (PAHs) are one of the most widespread organic environmental pollutants that pose a potential risk to marine biota. Although they occur as mixtures in the marine environment, only little information exists about their joint action on fish behavior. In 4-day tests with juvenile gilthead seabream (Sparus aurata) concentration-response analyses were performed for three PAH compounds--fluorene (FE), phenanthrene (PHE), and pyrene (PY).

An automated marine biomonitoring system for assessing water quality in real-time.

On-line behavioural monitoring systems are nowadays a common tool in ecotoxicological research. Although applied successfully to freshwater species, they are rarely used in the marine field. Here we present first results about the Marine On-line Biomonitor System (MOBS), a new automatic system for recording behavioural responses of marine and freshwater species.

Mixtures of estrogenic chemicals enhance vitellogenic response in sea bass.

Background: The potential impact of natural and synthetic estrogens on aquatic ecosystems has attracted considerable attention because it is currently accepted that their joint effects are more severe when they are present in mixtures. Although it is well-known that they occur as mixtures in the marine environment, there is little information about the combined effects of estrogenic chemicals on marine biota.

Objective: In 14-day tests with juvenile sea bass, we analyzed singly and in combination the estrogenic activity of estradiol (E(2)), ethynylestradiol (EE(2)), and bisphenol A (BPA) using vitellogenin induction as an end point.

Multi-level assessment of chronic toxicity of estuarine sediments with the amphipod Gammarus locusta: II. Organism and population-level endpoints.

This study aimed to test the performance of the amphipod Gammarus locusta (L.) in chronic sediment toxicity tests. It constitutes part of a multi-level assessment of chronic toxicity of estuarine sediments, integrating organism and population-level endpoints with biochemical markers responses.

Multi-level assessment of chronic toxicity of estuarine sediments with the amphipod Gammarus locusta: I. Biochemical endpoints.

We report on biomarker responses conducted as part of a multi-level assessment of the chronic toxicity of estuarine sediments to the amphipod Gammarus locusta. A companion article accounts for organism and population-level effects. Five moderately contaminated sediments from two Portuguese estuaries, Sado and Tagus, were assessed.