RESUMO
The concentrations of six metals (Ag, Cd, Cu, Hg, Pb, and Zn) were investigated and compared in three tissues (arms, digestive gland, and mantle) of three cephalopod species from the Tunisian waters: the common octopus (Octopus vulgaris), the common cuttlefish (Sepia officinalis), and the European squid (Loligo vulgaris). Whatever the species or the sites, the digestive gland displayed the highest concentrations of Ag, Cd, Cu, Pb, and Zn, highlighting its major role in their bioaccumulation and detoxification. This is also true for Hg but only for the digestive gland of O. vulgaris. Muscle from the arms and the mantle contained thus relatively low trace metal concentrations except for Hg in L. vulgaris and S. officinalis. Geographic comparison of metal concentrations in Tunisian cephalopods from three locations indicates that higher concentrations of Ag, Pb, and Hg were observed in cephalopods from northern and eastern coasts, whereas the highest Cd levels were detected in the southeastern, reflecting different conditions of exposure. Comparing the trace element concentrations between species, Ag, Cd, Cu, Hg, and Zn concentrations were the highest in the digestive gland of octopuses. This may be related to the differences in ecological features and swimming behavior among different cephalopod species. Effects of length and sex on metal levels were also considered, indicating a limited influence of sex on metal concentration.
Assuntos
Monitoramento Ambiental , Metais/metabolismo , Sepia/metabolismo , Poluentes Químicos da Água/metabolismo , AnimaisRESUMO
This study measured the concentrations of Hg, As, Ni, Cd, and Pb in six fish species commonly consumed in Kendari. Samples were bought within local markets from 2012 to 2017 at the end of the dry season. Results showed that mercury concentrations fluctuated between years and within species, except in the Caranx sexfasciatus, which showed no significant differences (Kruskall-Wallis, p-value > 0.05, df = 5) and an average concentration of 0.371 ± 0.162 µg g-1 DW. Arsenic was found in high concentrations across species and years and varied widely in C. sexfasciatus, the lowest value being 0.32 ± 0.01 µg g-1 DW in 2012 and the highest was 5.63 ± 1.89 µg g-1 DW in 2017. The highest nickel concentrations were found in 2016 across four of the six species. The fish samples displayed very low cadmium and lead concentrations throughout the study. In addition, the potential human health risk due to fish consumption was assessed. This showed that mercury is the only one of the five metals present in concentrations high enough to individually pose a potential hazard, the only metal likely to be accumulated beyond a safe concentration in Kendari. Chanos chanos never posed a toxicological risk based on the results of this research.
RESUMO
The development of human activities on French Atlantic coastlines (La Rochelle) lead to chronic pollution of the environment by organic (pesticides, hydrocarbons, agrochemicals) and inorganic (heavy metals) contaminants. These past years, several regulations have been implemented to preserve coastal environments. The purpose of this study was to perform biomonitoring of bivalve species using an outdoor caging technique. The goal of our work was to assess the impact of harbour's trace elements on the state of health of the marine bivalve Mimachlamys varia. First, various molecular defence biomarkers were measured: SOD (oxidative stress), GST (detoxification process), MDA (lipid peroxidation), and Laccase (immune reaction). Thus, in April 2016, scallops were collected at three caging sites, which differ by their levels of pollution, after transplantation into port areas (fairing, rainwater) and a control site (marsh). Bivalve samples were taken at three sampling dates (D0, D07, D21). Biomarker assays were performed in the digestive glands due to their bioaccumulation properties. The second aim was to explore the impacts of inorganic pollutants placed in environmental harbour's sites. After 21 days, the biomarker response of transplanted bivalves revealed a SOD decrease, Laccase and GST stimulations, higher concentrations in Cu, Fe, As, Co, Mn, Zn, Sn and no significant variation of MDA concentration. Our ecological relevance of biomarker approaches opens interesting perspectives to identify M. varia such as a pertinent marine sentinel species. The several selected biomarkers determined could confirm their ability to appraise the water quality of hydro-systems located in French coastlines, such as port areas.
Assuntos
Monitoramento Biológico/métodos , Pectinidae/fisiologia , Poluição da Água/estatística & dados numéricos , Animais , Biomarcadores/metabolismo , Bivalves/metabolismo , França , Atividades Humanas , Humanos , Hidrocarbonetos , Peroxidação de Lipídeos , Metais Pesados/análise , Estresse Oxidativo , Praguicidas , Oligoelementos/análise , Poluentes Químicos da Água/análiseRESUMO
The design and synthesis of the first fluorophore-conjugated SGLT2 inhibitors is described. The mode of linking the fluorophore to the SGLT2 pharmacophore was found to be crucial in achieving optimum potency. Superior potency to phlorizin was provided by examples containing TAMRA, BODIPY, Cy3B and NBD fluorophores.
Assuntos
Corantes Fluorescentes/síntese química , Corantes Fluorescentes/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose , Técnicas de Química Combinatória , Desenho de Fármacos , Corantes Fluorescentes/química , Estrutura Molecular , Florizina/farmacologiaRESUMO
Concentrations of cadmium (Cd), copper (Cu), mercury (Hg), and zinc (Zn) were determined by atomic absorption spectrophotometry in the muscle tissues (arms and mantle) of 3 commercial cephalopods (Loligo vulgaris, Octopus vulgaris, and Sepia officinalis) caught in 3 different Tunisian coastal regions. The highest concentrations found correspond to the essential elements Cu and Zn. Octopuses and cuttlefish showed the highest levels of those elements whereas squid presented with significantly higher values of Hg in both muscular tissues. This may be related to different feeding behavior and detoxification processes among benthic and pelagic cephalopods. Variation of element concentrations between seasons was different between species and seemed to be mostly dependent on the sampling site. From a public health standpoint, average concentrations of Cd, Cu, Hg, and Zn measured in edible tissues of cephalopods from this study did not reveal, in general, any risk for consumers. The estimated target hazard quotients for Cd and Hg for consumers of the selected species were below 1 and within the safety range for human health. Moreover, their consumption could provide in an important contribution to the daily dietary intake of Cu for the Tunisian population, especially regarding the consumption of octopus and cuttlefish muscles.
Assuntos
Cádmio/análise , Cobre/análise , Contaminação de Alimentos/análise , Mercúrio/análise , Micronutrientes/análise , Zinco/análise , Animais , Cefalópodes , Decapodiformes , Análise de Alimentos , Humanos , Valor Nutritivo , Medição de Risco , Alimentos Marinhos/análise , Estações do Ano , Espectrofotometria Atômica , TunísiaRESUMO
The application of trichloroacetic acid (TCA) as a shell extractant for preparation of soft body parts with reference to tissue metal concentrations (Cd, Cu, Pb, Zn) in shellfish has been evaluated on the example of the mud snail Hydrobia ulvae, a small marine prosobranch densely present in rocky and soft-bottom habitats of the eastern Atlantic. A solution of 0.1 M TCA was tested on individuals treated according to two different protocols: (1) thawed after freezing ("non-dried") and (2) thawed and air-dried to a constant weight ("dried"). Two points were investigated in detail to improve the method: individual soft tissue dry weight and tissue metal concentration following a standard digestion method. In both instances, the results were compared with those from manually dissected snails. Conditions for total shell decalcification of 60 individuals (3-4 mm long) were 5.5 h in 20 ml of 0.1 M TCA.No differences in individual soft tissue weight were observed between the treatments, indicating good efficiency of the TCA extraction with respect to weight of soft body parts. In contrast, tissue metal concentrations varied among treatments. The TCA extraction of the dried animals had a good recovery for Cd, most likely due to the lower solubility of Cd vital cellular components (proteins and mineral concretions) from the dried tissue. Satisfactory recoveries of the tissue concentrations of Cu and Pb were obtained for the non-dried individuals. This might be related to the specific distribution of metals in the organism (namely in the digestive glands and gonads) and their different chemical reactivity with TCA after the tissue was dried. Limited susceptibility of Zn-bearing protein bindings to complexing with TCA also accounts for significantly lower concentrations of Zn in the mud snail's soft tissue that was extracted. The 0.1 M TCA solution is therefore recommended for extraction of the shells of Hydrobia ulvae for tissue determination of Cd, Cu and Pb; however the treatment protocol does affect metal recovery and thus a consistent procedure should be followed. The extracted metals from the soft tissues and shells of the mud snails (on the basis of both metal concentrations and contents) were ranked in order of increasing contribution of soft body parts to the total (shell+tissue): PbAssuntos
Metais Pesados/análise
, Caramujos/química
, Manejo de Espécimes/métodos
, Ácido Tricloroacético/química
, Animais
, Dessecação
, Dissecação
, Congelamento
RESUMO
Recent studies on the ant phylogeny are mainly based on the molecular analyses of extant subfamilies and do not include the extinct, only Cretaceous subfamily Sphecomyrminae. However, the latter is of major importance for ant relationships, as it is considered the most basal subfamily. Therefore, each new discovery of a Mesozoic ant is of high interest for improving our understanding of their early history and basal relationships. In this paper, a new sphecomyrmine ant, allied to the Burmese amber genus Haidomyrmex, is described from mid-Cretaceous amber of France as Haidomyrmodes mammuthus gen. and sp. n. The diagnosis of the tribe Haidomyrmecini is emended based on the new type material, which includes a gyne (alate female) and two incomplete workers. The genus Sphecomyrmodes, hitherto known by a single species from Burmese amber, is also reported and a new species described as S. occidentalis sp. n. after two workers remarkably preserved in a single piece of Early Cenomanian French amber. The new fossils provide additional information on early ant diversity and relationships and demonstrate that the monophyly of the Sphecomyrminae, as currently defined, is still weakly supported.
Assuntos
Âmbar , Formigas , Fósseis , Animais , Formigas/anatomia & histologia , Formigas/classificação , Extremidades/anatomia & histologia , França , Paleontologia/métodos , Filogenia , Asas de Animais/anatomia & histologiaRESUMO
Nuclear factor-kappaB (NF-kappaB), a transcription factor with a critical role in promoting inflammation and cell survival, is constitutively activated in estrogen-receptor (ER)-negative breast cancer and is considered a potential therapeutic target for this type of neoplasia. We have previously demonstrated that cyclopentenone prostaglandins are potent inhibitors of NF-kappaB activation by inflammatory cytokines, mitogens, and viral infection, via direct binding and modification of the beta subunit of the IkappaB kinase complex (IKK). Herein, we describe the NF-kappaB-dependent anticancer activity of natural and synthetic cyclopentenone IKK inhibitors. We demonstrate that the natural cyclopentenone 15-deoxy-Delta(12,14)prostaglandin J(2) (15d-PGJ(2)) is a potent inhibitor of constitutive IkappaB-kinase and NF-kappaB activities in chemotherapy-resistant ER-negative breast cancer cells. 15d-PGJ(2)-induced inhibition of NF-kappaB function is rapidly followed by down-regulation of NF-kappaB-dependent antiapoptotic proteins cIAPs 1/2, Bcl-X(L), and cellular FLICE-inhibitory protein, leading to caspase activation and induction of apoptosis in breast cancer cells resistant to treatment with paclitaxel and doxorubicin. We then demonstrate that the cyclopentenone ring structure is responsible for these activities, and we identify a new synthetic cyclopentenone derivative, 3-tert-butyldimethylsilyloxy-5-(E)-iso-propylmethylenecyclopent-2-enone (CTC-35), as a potent NF-kappaB inhibitor with proapoptotic activity in ER-negative breast cancer cells. The results open new perspectives in the search for novel proapoptotic molecules effective in the treatment of cancers presenting aberrant NF-kappaB regulation.