The validation of the Barcelona Orthorexia Scale-Spanish version: evidence from the general population.

PURPOSE: To validate the Spanish version of Barcelona Orthorexia Scale (BOS) in general population, analyzing its items and both its internal structure and psychometric properties (internal consistency and temporal stability). In addition, the relationship between ON and external measures of attitudes towards food was assessed. METHOD: The general population sample consisted of 446 women and 104 men, aged between 18.31 and 69.44 years (M = 36.03; SD = 12.46). Of these, 39 participants answered again the questionnaires after one month from the first application. The assessment instruments were a sociodemographic questionnaire, the BOS, the Eating Attitudes Test-26 (EAT-26) and the Dutch Eating Behavior Questionnaire (DEBQ). RESULTS: The final version of the BOS is composed of 35 items. Exploratory factor analysis extracted an internal structure of 5 factors (Behavioral, Concern for healthy food, Attitudes and beliefs about food, Vital achievement and Emotional discomfort). The BOS-35 and the factors presented good internal consistency (α = .80-.90), and an adequate temporal stability (r = .62-.88). The highest association was observed between the Emotional Distress (BOS) and the Diet subscale (EAT-26; r = .51). CONCLUSIONS: This first validation of the BOS has shown adequate psychometric properties, being a valid and reliable instrument to assess ON in the general population. Level of evidence Level II: Evidence obtained from well-designed controlled trials without randomization.

Study of antibiotic resistance in freshwater ecosystems with low anthropogenic impact.

This study aimed to investigate the bacterial diversity and the background level of antibiotic resistance in two freshwater ecosystems with low anthropogenic impact in order to evaluate the presence of natural antimicrobial resistance in these areas and its potential to spread downstream. Water samples from a pre-Alpine and an Apennine river (Variola and Tiber, respectively) were collected in three different sampling campaigns and bacterial diversity was assessed by 16S sequencing, while the presence of bacteria resistant to five antibiotics was screened using a culturable approach. Overall bacterial load was higher in the Tiber River compared with the Variola River. Furthermore, the study revealed the presence of resistant bacteria, especially the Tiber River showed, for each sampling, the presence of resistance to all antibiotics tested, while for the Variola River, the detected resistance was variable, comprising two or more antibiotics. Screening of two resistance genes on a total of one hundred eighteen bacterial isolates from the two rivers showed that blaTEM, conferring resistance to ß-lactam antibiotics, was dominant and present in ~58 % of isolates compared to only ~9 % for mefA/E conferring resistance to macrolides. Moreover, ß-lactam resistance was detected in various isolates showing also resistance to additional antibiotics such as macrolides, aminoglycosides and tetracyclines. These observations would suggest the presence of co-resistant bacteria even in non-anthropogenic environments and this resistance may spread from the environment to humans and/or animals.

Holistic approach to chemical and microbiological quality of aquatic ecosystems impacted by wastewater effluent discharges.

Wastewater treatment plants (WWTPs) collect wastewater from various sources and use different treatment processes to reduce the load of pollutants in the environment. Since the removal of many chemical pollutants and bacteria by WWTPs is incomplete, they constitute a potential source of contaminants. The continuous release of contaminants through WWTP effluents can compromise the health of the aquatic ecosystems, even if they occur at very low concentrations. The main objective of this work was to characterize, over a period of four months, the treatment steps starting from income to the effluent and 5 km downstream to the receiving river. In this context, the efficiency removal of chemical pollutants (e.g. hormones and pharmaceuticals, including antibiotics) and bacteria was assessed in a WWTP case study by using a holistic approach. It embraces different chemical and biological-based methods, such as pharmaceutical analysis by HPLC-MSMS, growth rate inhibition in algae, ligand binding estrogen receptor assay, microbial community study by 16S and shotgun sequencing along with relative quantification of resistance genes by quantitative polymerase chain reaction. Although both, chemical and biological-based methods showed a significant reduction of the pollutant burden in effluent and surface waters compared to the influent of the WWTP, no complete removal of pollutants, pathogens and antibiotic resistance genes was observed.

Family perceptions and experiences of living with patients with fibromyalgia syndrome.

PURPOSE: To explore the perception of the illness and the experience of the illness for relatives of fibromyalgia syndrome (FMS) patients. MATERIALS AND METHODS: This qualitative interpretative study adopted a grounded theory research methodology with a purposive sample. We conducted a focus group with 11 family members of FMS patients. There were six men and five women, five were spouses and six were children (four husbands and one wife, and five daughters and one son). RESULTS: Three categories of family perceptions of FMS emerged: (1) manifestations of FMS; (2) FMS is regarded as a psychological problem; (3) FMS interferes with traditional gender roles. Three categories of family members' experience of living with FMS patients were identified: (1) emotional concerns and exhaustion; (2) overprotective family members; and (3) escape coping. CONCLUSIONS: Family members feel emotionally burdened, can be overprotective and over-involved and find it difficult to set limits ultimately succumbing to a vicious cycle of caregiving and emotional exhaustion from which they find it difficult to escape. As the perceptions and experiences of family members of FMS patients are not commonly studied, the present findings offer new insights for families and elucidate important points of intervention.Implications for rehabilitationBecause family members tend to dismiss fibromyalgia as a psychological problem for which ignoring or distracting the patient is the best approach to coping, rehabilitation programs should give family members education and training to develop the ability to better understand fibromyalgia and reduce stereotypes about the condition.Rehabilitation programs should work to identify and manage marital and family systems dysfunction that may be interfering with fibromyalgia patients' adjustment and quality of life.Family members often engage in maladaptive escape coping to manage the demands of living with patients with fibromyalgia, and rehabilitation professionals should be ready to engage and refer to allied specialists to assist family members in finding alternatives for more effective coping approaches that improve patient and family mental health and social relations.Rehabilitation programs for fibromyalgia patients should use a gender perspective and emphasize patient and spouse equality in activities of daily living as many patients and family members feel uncomfortable about not fulfilling traditional gender roles.

Impact of Viral Decontamination Method on Cytokine Profile of COVID-19 Patients.

COVID-19 related morbidity and mortality have been often attributed to an exaggerated immune response. The role of cytokines and chemokines in COVID-19 and their contributions to illness severity are known, and thus their profiling from patient bronchoalveolar lavage (BAL) samples would help in understanding the disease progression. To date, limited studies have been performed on COVID-19 BAL samples, as the manipulation of such specimens (potentially containing live viruses) requires several laboratorial precautions, such as personnel training and special equipment, a requirement that not all laboratories can fulfil. Here, we assessed two fast and easily applicable methods (ultrafiltration and ultraviolet-C irradiation) for their impact on viral load removal or inactivation, respectively and on cytokine profiles preservation. Eight samples of BAL fluids from SARS-CoV2 patients with high viral load were tested. For both methods, complete removal was confirmed by lack of viral replication in Vero E6 cells and by RT-qPCR. Although both methods showed to remove completely the active SARS-CoV2 viral load, only UVC treatment has little or no quantitative effect on total cytokines/chemokines measurements, however cytokines profile and relative ratios are preserved or minimally altered when compared data obtained by the two different decontamination methods. Sample preparation and manipulation can greatly affect the analytical results; therefore, understanding if changes occurred after sample processing is of outmost importance for reliable data and can be useful to improve clinical practice.

Knowledge gaps in the assessment of antimicrobial resistance in surface waters.

The spread of antibiotic resistance in the water environment has been widely described. However, still many knowledge gaps exist regarding the selection pressure from antibiotics, heavy metals and other substances present in surface waters as a result of anthropogenic activities, as well as the extent and impact of this phenomenon on aquatic organisms and humans. In particular, the relationship between environmental concentrations of antibiotics and the acquisition of ARGs by antibiotic-sensitive bacteria as well as the impact of heavy metals and other selective agents on antimicrobial resistance (AMR) need to be defined. Currently, established safety values are based on the effects of antibiotic toxicity neglecting the question of AMR spread. In turn, risk assessment of antibiotics in waterbodies remains a complex question implicating multiple variables and unknowns reinforced by the lack of harmonized protocols and official guidelines. In the present review, we discussed current state-of-the-art and the knowledge gaps related to pressure exerted by antibiotics and heavy metals on aquatic environments and their relationship to the spread of AMR. Along with this latter, we reflected on (i) the risk assessment in surface waters, (ii) selective pressures contributing to its transfer and propagation and (iii) the advantages of metagenomics in investigating AMR. Furthermore, the role of microplastics in co-selection for metal and antibiotic resistance, together with the need for more studies in freshwater are highlighted.

SARS-CoV-2 detection in wastewater using multiplex quantitative PCR.

A multiplex reverse transcription quantitative PCR (RT-qPCR)-based method was designed for the simultaneous detection of different SARS-CoV-2 genes. In this study, we used three target genes encoding for the nucleocapsid 1 and 3 (N1, N3), and the spike (S) proteins, all commonly used in the detection of SARS-CoV-2 in human and environmental samples. The performance of the multiplex assay, compared to the single assay was assessed for the standard calibration curve, required for absolute quantification, and then, for the real environmental samples to detect SARS-CoV-2. For this latter, four environmental samples were collected at a local wastewater treatment plant (WWTP). The results showed that the cycle threshold (Ct) values of the multiplex were comparable to the values obtained by the singleplex PCR. The amplification of the three target genes indicated the presence of SARS-CoV-2 in the four water samples with an increasing trend in February and these results were confirmed in the multiplex approach, showing the robustness of this method and its applicability for the relative abundance analysis among the samples. Overall, both the laboratory and field work results demonstrated that the multiplex PCR assay developed in this study could provide a method for SARS-CoV-2 detection as robust as the single qPCR, but faster and cost-effective, reducing by three times the number of reactions, and consequently the handling time and reagents.

Estrogenicity of chemical mixtures revealed by a panel of bioassays.

Estrogenic compounds are widely released to surface waters and may cause adverse effects to sensitive aquatic species. Three hormones, estrone, 17ß-estradiol and 17α-ethinylestradiol, are of particular concern as they are bioactive at very low concentrations. Current analytical methods are not all sensitive enough for monitoring these substances in water and do not cover mixture effects. Bioassays could complement chemical analysis since they detect the overall effect of complex mixtures. Here, four chemical mixtures and two hormone mixtures were prepared and tested as reference materials together with two environmental water samples by eight laboratories employing nine in vitro and in vivo bioassays covering different steps involved in the estrogenic response. The reference materials included priority substances under the European Water Framework Directive, hormones and other emerging pollutants. Each substance in the mixture was present at its proposed safety limit concentration (EQS) in the European legislation. The in vitro bioassays detected the estrogenic effect of chemical mixtures even when 17ß-estradiol was not present but differences in responsiveness were observed. LiBERA was the most responsive, followed by LYES. The additive effect of the hormones was captured by ERα-CALUX, MELN, LYES and LiBERA. Particularly, all in vitro bioassays detected the estrogenic effects in environmental water samples (EEQ values in the range of 0.75-304 × EQS), although the concentrations of hormones were below the limit of quantification in analytical measurements. The present study confirms the applicability of reference materials for estrogenic effects' detection through bioassays and indicates possible methodological drawbacks of some of them that may lead to false negative/positive outcomes. The observed difference in responsiveness among bioassays - based on mixture composition - is probably due to biological differences between them, suggesting that panels of bioassays with different characteristics should be applied according to specific environmental pollution conditions.

Arsenosugar standards extracted from algae: Isolation, characterization and use for identification and quantification purposes.

Sulfate (SO4-sug) and sulfonate (SO3-sug) arsenosugar standard solutions were obtained using preparative liquid chromatography. Several commercial algae samples were characterized (total contents and speciation) to select the most appropriate in relation to their arsenosugar contents. Water extracts from the selected sample (Fucus vesiculosus) were fractionated using a Hamilton PRP-X100 preparative column, and the presence of arsenic species in the isolated fractions was ascertained by IC-ICP-MS. Two of the fractions successfully presented only one arsenic species corresponding to sulfate and sulfonate arsenosugars at suitable concentrations. To unequivocally confirm the presence of both compounds, high-resolution mass spectrometry (ESI-TOF/MS) was used and the exact mass determined with errors lower than 0.5 ppm. The standard solutions obtained were successfully used to identify and quantify SO4-sug and SO3-sug in several edible algae samples purchased in local market. Total arsenic content for analyzed samples ranged from 34 to 57 mg kg-1, concentration values found for SO3-sug ranged from 5 to 36 mg As kg-1 and SO4-sug was only found in fucus with a concentration of 9.3 mg As kg-1.

DNA Barcoding of Philippine Herbal Medicinal Products.

The Philippine government established the Traditional and Alternative Medicine Act in 1997 to promote traditionally used herbal products and to provide an effective yet affordable alternative to conventional medicines. However, government regulation of herbal medicinal products (HMPs) is not stringent, relying only on submitted quality data from the manufacturer. In this study we validated the taxonomic identity of 26 plant samples contained within 22 HMPs, each produced by different local manufacturers, through DNA barcoding of the nuclear internal transcribed spacer-2 (ITS2) region. We recovered 19 ITS2 barcodes from 26 samples. These were compared to sequences in GenBank using MEGABLAST, but ambiguous results (similar max scores for different species) were phylogenetically analyzed. Twelve of the 19 samples matched the indicated species on the product label, three were equivocal in specific identity but were placed in the expected genus, and four other samples from three manufacturers contained contamination and/or substitution. GenBank's reference database was at times problematic because some sequences were lacking or were misidentified, but the database was still useful. Overall, ITS2 barcoding was successful in authenticating the HMPs, and it is recommended during the premarket evaluation process so as to obtain a certificate of registration from the government. The government should also develop a comprehensive database of barcodes for Philippine plants, and should prioritize the development of the traditional pharmacopeia because many locally produced HMPs are not indigenous.

How low can they go when going with the flow? Tolerance of egg and larval fishes to rapid decompression.

Egg and larval fish that drift downstream are likely to encounter river infrastructure and consequently rapid decompression, which may result in significant injury. Pressure-related injury (or barotrauma) has been shown in juvenile fishes when pressure falls sufficiently below that at which the fish has acclimated. There is a presumption that eggs and larvae may be at least as, if not more, susceptible to barotrauma injury because they are far less-developed and more fragile than juveniles, but studies to date report inconsistent results and none have considered the relationship between pressure change and barotrauma over a sufficiently broad range of pressure changes to enable tolerances to be properly determined. To address this, we exposed eggs and larvae of three physoclistic species to rapid decompression in a barometric chamber over a broad range of discrete pressure changes. Eggs, but not larvae, were unaffected by all levels of decompression tested. At exposure pressures below ∼40 kPa, or ∼40% of surface pressure, swim bladder deflation occurred in all species and internal haemorrhage was observed in one species. None of these injuries killed the fish within 24 h, but subsequent mortality cannot be excluded. Consequently, if larval drift is expected where river infrastructure is present, adopting design or operational features which maintain exposure pressures at 40% or more of the pressure to which drifting larvae are acclimated may afford greater protection for resident fishes.

qRT-PCR evaluation of the transcriptional response of zebra mussel to heavy metals.

BACKGROUND: The transcriptional response of adult zebra mussels (Dreissena polymorpha) to heavy metals (mercury, copper, and cadmium) was analyzed by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) to study the coordinated regulation of different metal-, oxidative stress- and xenobiotic defence-related genes in gills and digestive gland. Regulatory network analyses allowed the comparison of this response between different species and taxa. RESULTS: Chemometric analyses allowed identifying the effects of these metals clearly separating control and treated samples of both tissues. Interactions between the different genes, either in the same or between both tissues, were analysed to identify correlations and to propose stress-related genes' regulatory networks. These networks were finally compared with existing data from human, mouse, zebrafish, Drosophila and the roundworm to evaluate their mechanistically-known response to metals (and to stressors in general) with the correlations observed in the still poorly-known, invasive zebra mussel. CONCLUSIONS: Our analyses found a general conservation of regulation genes and of their interactions among the different considered species, and may serve as a guide to extrapolate regulatory data from model species to lesser-known environmentally (or medically) relevant species.

Genetic and phenoptypic differentiation of zebra mussel populations colonizing Spanish river basins.

Zebra mussel populations in Ebro and Mijares Rivers (northern Spain) were analyzed to study the mechanisms by which this aquatic species deals with pollution. Variability analyses of mitochondrial cytochrome oxidase I gene and of one nuclear microsatellite were performed for ten populations from the Ebro River and one from the Mijares River. Comparison of these results with those from five additional European populations indicated that the Spanish populations constitute a homogeneous gene pool. Transcriptome analyses of gill samples from a subset of the Spanish populations showed changes on expression levels that correlated with variations in general fitness and loads of heavy metals. The less polluted upstream Ebro populations showed overexpression of mitochondrial and cell proliferation-related genes compared to the more polluted, downstream Ebro populations. Our data indicate that heavy metals were the main factors explaining these transcriptomic patterns, and that zebra mussel is resilient to pollutants (like mercury and organochlorine compounds) proved to be extremely toxic to vertebrates. We propose that zebra mussel populations sharing a common gene pool may acclimate to different levels and forms of pollution through modulations in their transcriptomic profile, although direct selection on genes showing differential expression patterns cannot be ruled out.

Transcriptomic seasonal variations in a natural population of zebra mussel (Dreissena polymorpha).

The zebra mussel Dreissena polymorpha is a Caspian Sea bivalve that colonized freshwater bodies worldwide during the XX century. To analyze the impact of seasonal and environmental variations on the physiology and metabolism of this invasive species, we developed a custom microarray using 4057 publicly available DNA sequences from Dreissena and other related genera. Transcriptome profiles were analyzed using half-body samples from a relatively clean site (Riba-Roja, low Ebro River, N.E. Spain), at three different stages of the annual cycle: Pre-spawning (February), spawning (June), and gonad resorption (September). Transcripts from a total of 745 unique sequences showed significant changes among these three groups of samples. Functional characterization of these transcripts based on their closest known homologues showed that genes involved in stress defense (oxidative and infection) were overrepresented in September, whereas genes related to reproductive functions were overrepresented in the spawning and pre-spawning periods. This transcriptomic information can help to identify developmental stages at which the organism is more vulnerable for future control strategies. These data will also contribute to the implementation of gene expression-based assays for pollution monitoring in water bodies harboring stable zebra mussel populations.

Associação entre o ganho de peso e a prevalência e gravidade de sibilância e asma no primeiro ano de vida / Association between weight gain and the prevalence and severity of wheezing and asthma in the first year of life

Objetivo: Avaliar a relação entre diferentes padrões de ganho de peso no primeiro ano de vidae a prevalência e gravidade de sibilância e asma em crianças. Métodos: Foram analisadas asrespostas ao questionário EISL de 9.159 pais moradores das cidades de São Paulo, Recife, Cuiabá,Curitiba e Belém. Os dados referidos do peso de nascimento e com um ano de vida foram convertidos em escore z (z). Foram considerados como tendo ganho de peso acelerado aqueles com diferença entre os pesos superior a 0,67 z, e ganho de peso excessivo aqueles com diferença superior a 2,01 z. Resultados: Ganho de peso acelerado foi observado em 55,7% dos lactentes,e ganho excessivo em 20,8%. Lactentes com ganho de peso acelerado apresentaram, de modosignificante, maior prevalência de sibilância recorrente (18,9% vs 18,2%) e de hospitalizaçãopor sibilância (8,9% vs 7,5%). Entre os lactentes com ganho de peso excessivo houve, de modo significante, maior prevalência de hospitalização por sibilância (10,1% vs 7,8%) e do diagnóstico médico de asma (8,7% vs 7,3%). A presença de aleitamento materno por pelo menos seis mesesfoi associada de forma significante com menor prevalência de ganho de peso acelerado (45,2% vs 51,4%). Conclusões: A maioria dos lactentes avaliados apresentou ganho de peso superior ao esperado durante o primeiro ano de vida. Ganho de peso acelerado e ganho de peso excessivono primeiro ano de vida foram associados a formas mais graves de sibilância, enquanto que oganho de peso excessivo foi associado ao diagnóstico médico de asma, independentemente dapresença do aleitamento materno.

Objective: To evaluate the relationship between different patterns of weight gain in the first year of life and the prevalence and severity of wheezing and asthma in infants. Methods: Responses of 9,159 parents to the questionnaire of the Estudio Internacional de Sibilancias en Lactantes (EISL, International Study of Wheezing in Infants) were analyzed. Families lived in the cities of São Paulo,Recife, Cuiabá, and Belém. Reported weight at birth and at one year were converted to z scores (z). Rapid weight gain was defined as a difference in weight greater than 0.67z, and excessive weight gain, greater than 2.01z. Results: Rapid weight gain was observed in 55.7% of the infants,and excessive weight gain in 20.8%. Infants with rapid weight gain showed a significantly higher prevalence of recurrent wheezing (18.9% vs. 18.2%) and hospitalization for wheezing (8.9% vs. 7.5%). Infants with excessive weight gain had a significantly higher prevalence of hospitalizationfor wheezing (10.1% vs. 7.8%) and medical diagnosis of asthma (8.7% vs. 7.3%). Breastfeeding for at least six months was significantly less frequent among infants with rapid weight gain (45.2% vs. 51.4%). Conclusions: The majority of the infants evaluated showed weight gain above theexpected in the first year of life. Rapid weight gain and excessive weight gain in the first year of life were significantly associated with more severe patterns of wheezing in infancy, and excessive weight gain was also associated with a medical diagnosis of asthma, regardless of the presence of breastfeeding.

Abcb and Abcc transporter homologs are expressed and active in larvae and adults of zebra mussel and induced by chemical stress.

Multixenobiotic resistance (MXR) of aquatic invertebrates has so far been associated with cellular efflux activity mediated by P-glycoprotein (ABCB1) and MRP (multidrug resistance protein; ABCC) type ABC (ATP binding cassette) transporters. Expression and activity of an abcb1/Abcb1 homolog has been shown in eggs and larvae of the zebra mussel Dreissena polymorpha. Here we report identification of a partial cDNA sequence of an abcc/Abcc homolog from zebra mussel that is transcribed and active as a cellular efflux transporter in embryos and gill tissue of adult mussels. Transcript expression levels were comparatively low in eggs and sharply increased after fertilization, then maintaining high expression levels in 1 and 2 dpf (days post fertilization) larvae. MK571, a known inhibitor of mammalian ABCC transporters, blocks efflux of calcein-am in larvae and gill tissue as indicated by elevated calcein fluorescence; this indicates the presence of active Abcc protein in cells of the larvae and gills. Dacthal and mercury used as chemical stressors both induced expression of abcb1 and abcc mRNAs in larvae; accordingly, assays with calcein-am and ABCB1 inhibitor reversin 205 and ABCC inhibitor MK571 indicated enhanced Abcb1 and Abcc efflux activities. Responses to chemicals were different in gills, where abcb1 transcript abundances were enhanced in dacthal and mercury treatments, whereas abcc mRNA was only increased with mercury. Abcb1 and Abcc activities did not in all cases show increases that were according to respective mRNA levels; thus, Abcc activity was significantly higher with dacthal, whereas Abcb1 activity was unchanged with mercury. Our data indicate that abcb1/Abcb1 and abcc/Abcc transporters are expressed and active in larvae and adult stages of zebra mussel. Expression of both genes is induced as cellular stress response, but regulation appears to differ in larvae and tissue of adult stages.

Structural and molecular analysis of pollution-linked deformities in a natural Aphanius fasciatus (Valenciennes, 1821) population from the Tunisian coast.

The Eastern coast of Tunisia hosts a mosaic of populations of the Mediterranean killifish A. fasciatus, an excellent monitoring species for the analysis of environmental impact in coastal Mediterranean areas. Among these populations, fish from the Sfax area, in the Gulf of Gabès, are known for presenting a high prevalence of different physiological alterations, including spinal deformation. Compared to a reference clean area, Luza, Sfax water and sediments are polluted with heavy metals (20 to 40 times more Cd, for example) and other compounds like PAHs (10 times higher levels). Histological analyses of deformed fish from this area showed an abnormal abundance of collagen fibers infiltrated in the spinal area, either as a physiological mechanism to alleviate the consequences of the deformation of the bones or as a secondary effect of the same pathological/toxicity mechanism inducing bone deformation. Deformed fish from Sfax showed elevated (4-5 fold) levels of transcripts from the collagen COL1A2 gene in bone tissue, compared to either non-deformed animals from the same location or normal animals from the reference Luza site. These results are consistent with an overexpression of collagen in the bone tissue, in agreement with the histological results. We propose that the deformation observed in the Sfax Aphanius population is a degenerative process occurring in adult animals and probably terminal, as it results in severe limitations on the fish capacity to swim, to catch food, and ultimately to survive.

Transcriptional response of stress genes to metal exposure in zebra mussel larvae and adults.

Development of stress markers for the invader freshwater zebra mussel (Dreissena polymorpha) is of great interest for both conservation and biomonitoring purposes. Gene expression profiles of several putative or already established gene expression stress markers (Metallothionein, Superoxide dismutase, Catalase, Glutathione S transferase, Glutathione peroxidase, Cytochrome c oxidase, the multixenobiotic resistance P-gp1, and heat shock proteins HSP70 and HSP90) were analyzed by quantitative Real-Time PCR in adults and pediveliger larvae after exposure to metals (Hg, Cu, Cd). A defined pattern of coordinated responses to metal exposure and, presumably, to oxidative stress was observed in gills and digestive gland from adults. A similar, albeit partial response was observed in larvae, indicating an early development of stress-related gene responses in zebra mussel. The tools developed in this study may be useful both for future control strategies and for the use of zebra mussel as sentinel species in water courses with stable populations.

Decontamination trends in the aquacultured fish gilthead seabream (Sparus aurata) after feeding long-term a PCDD/F spiked feed.

Aquacultured fish gilthead seabream (Sparusaurata), previously exposed to low levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) trough the diet for a 13 months period, were fed on a clean feed for another 22 months. Gilthead seabream is a protandrous hermaphrodite species and this "decontamination" period coincided with the stages of sex differentiation, maturity and reproduction of the fish. PCDD/F levels in the fish tissues (i.e. muscle, liver, perivisceral fat and gonads), expressed in pg WHO-TEQg⁻¹ fresh weight, showed a general decreasing trend during the "decontamination" period. However, this general trend varied among tissues and was also dependent on sex and lipid contents. Toxicological effects affecting fish behaviour and hepatic marker responses were also evaluated. The results pointed out that exposure to PCDD/Fs did not have an impact on fish development and reproduction, since the proportion of sexes found after the sex reversal process was within the normal range described for this species. In addition, long-term exposure to low PCDD/F levels did not significantly affect the response of most of the biochemical markers considered. On the contrary, some of them (e.g. EROD activity) showed variations in their responses during the sex differentiation process and onwards. Finally, the hepatic AhR mRNA levels increased during dioxin exposure but they returned to values typical for non-exposed fish after the "decontamination" period.