Structures related to pheromone storage in alar androconia and the female abdominal scent gland of Heliconius erato phyllis, Heliconius ethilla narcaea, and Heliconius besckei (Lepidoptera: Nymphalidae: Heliconiinae).

We describe the morphology of alar androconia and the female abdominal scent gland of Heliconius erato phyllis, Heliconius ethilla narcaea, and Heliconius besckei. Androconial scales of Heliconius, which are arranged in overlapping wing bands, release pheromones during courtship, probably through vibratory movements of male wings over the female to induce her to mate. An antiaphrodisiac is produced by glands located in the valves of the male and is transferred during copulation to the yellow dorsal abdominal sac present in the virgin female, causing this sac to emit a scent that reduces the attractiveness of the female for courtship with other males. Stereomicroscopy, SEM, and TEM analyses were conducted to describe the morphology of the internal and external scales and the external abdominal scent sac. The findings revealed different sizes of external androconial scales and an internal group of porous structural vesicles that are probably related to the preservation of internal space, reception and storage of secretions, and elimination of volatiles when the male is actively involved in courtship. Translucent projections on the female abdominal scent sac create open reservoirs for the reception, storage, and emission of antiaphrodisiac volatiles along with stink clubs. Male valve denticles vary in form and probably attach securely to the female sac during mating, thus ensuring secretion transfer. These features are discussed in the context of a comparative analysis.

Silver nanoparticles and dissolved silver activate contrasting immune responses and stress-induced heat shock protein expression in sea urchin.

Using immune cells of sea urchin Strongylocentrotus droebachiensis in early development as a model, the cellular protective mechanisms against ionic and poly(allylamine)-coated silver nanoparticle (AgNPs; 14 ± 6 nm) treatments at 100 µg L-1 were investigated. Oxidative stress, heat shock protein expression, and pigment production by spherulocytes were determined as well as AgNP translocation pathways and their multiple effects on circulating coelomocytes. Sea urchins showed an increasing resilience to Ag over time because ionic Ag is accumulated in a steady way, although nanoAg levels dropped between 48 h and 96 h. A clotting reaction emerged on tissues injured by dissolved Ag (present as chloro-complexes in seawater) between 12 h and 48 h. Silver contamination and nutritional state influenced the production of reactive oxygen species. After passing through coelomic sinuses and gut, AgNPs were found in coelomocytes. Inside blood vessels, apoptosis-like processes appeared in coelomocytes highly contaminated by poly(allylamine)-coated AgNPs. Increasing levels of Ag accumulated by urchins once exposed to AgNPs pointed to a Trojan-horse mechanism operating over 12-d exposure. However, under short-term treatments, physical interactions of poly(allylamine)-coated AgNPs with cell structures might be, at some point, predominant and responsible for the highest levels of stress-related proteins detected. The present study is the first report detailing nano-translocation in a marine organism and multiple mechanisms by which sea urchin cells can deal with toxic AgNPs. Environ Toxicol Chem 2017;36:1872-1886. © 2016 SETAC.

A multibiomarker evaluation of urban, industrial, and agricultural exposure of small characins in a large freshwater basin in southern Brazil.

Iguaçu River is the second most polluted river of Brazil. It receives agrochemicals and contaminants of urban and industrial sources along its course. A multibiomarker approach was employed here to evaluate the health of a small characin (Astyanax spp.) at two sites along the river, sampled during a dry (autumn) and a rainy (spring) season. Biomarkers were condition factor and somatic indices (gonads and liver); genetic damage (comet assay and micronucleus test); enzyme activities such as hepatic catalase (CAT) and glutathione S-transferase (GST), lipoperoxidation (LPO), branchial and renal carbonic anhydrase (CA), acetylcholinesterase (AChE) in the muscle and the brain, histopathology of the liver and gills, and concentrations of polycyclic aromatic hydrocarbons (PAHs) in bile. There were no consistent differences in biomarker responses between the two study sites. Some biomarkers revealed greater potential impact in the rainy season, when increased amounts of contaminants are washed into the river (combined CAT inhibition and LPO increase, CA upregulation). Other biomarkers, however, revealed potential greater impact in the dry season, when contaminants potentially concentrate (GST induction, AChE inhibition, and liver histopathological alterations). Although of a complex nature, field experiments such as this provide rich data for monitoring protocols and assessment of general risk of exposure to pollutants of river systems.

Chronic genetic damages in Geophagus brasiliensis exposed to anthropic impact in estuarine lakes at Santa Catarina coast--southern of Brazil.

Biological monitoring through animals exposed to pollutants using biomarkers provides a promising tool for the identification of pollutants that may cause damage to human health and/or to sustainability of ecosystems. The effects of pollutants in fish tissues are important tools to understand the impact of human activities in natural ecosystems. The aim of this work was to study the water quality of two estuarine lakes in Santa Catarina, Brazil (Camacho Lake and Santa Marta Lake). Geophagus brasiliensis is a species widely distributed in Brazil and was used in this work. Comet assays in peripheral red blood and kidney cells, micronucleus tests in peripheral red blood cells, measurements of acetylcholinesterase activity in axial muscle and histopathological analysis of liver were used as biomarkers. Three sampling campaigns were undertaken in November 2004, June 2005 and November 2005. Thirty adult animals were sampled from each of three different sites (P1--Santa Marta Lake, P2 and P3--Camacho Lake). A negative control was sampled in a non-polluted site at Costa Ecological Park, Paraná. The positive control for genotoxicity was obtained by treating animals with copper sulphate. The results showed that both studied lakes are impacted by potential genotoxic substances. Severe lesions in liver of G. brasiliensis were also observed. The inhibition of acetylcholinesterase activity suggests the presence of pesticides or metals in the studied sites. This work shows that the water quality of Santa Marta and Camacho Lakes have been compromised and further control source of pollutants into these ecosystems is required.

Immunological responses, histopathological finding and disease resistance of blue mussel (Mytilus edulis) exposed to treated and untreated municipal wastewater.

This study provides new information on the response of the immune system of Mytilus edulis exposed to untreated and treated sewage, linking immune response to ecologically relevant endpoints, such as disease resistance. Our goal was to assess the potential effects of sewage on the immune system (phagocytic activity and production of cytotoxic metabolites, disease resistance) and gills (light microscope) of mussels through a bioassay and field study in an estuarine receiving environment (RE). A semi-static experiment was developed in a wastewater treatment plant in New Glasgow, NS Canada. Mussels were exposed for 21 days to 12.5%, 25%, 50% and 100% of untreated sewage influent and artificial seawater control. Sampling occurred after 7, 14 and 21 days of exposure. In the field study, eight sites were selected in East River and Pictou Harbour, NS, positioned upstream and downstream of sewage effluents outfalls. Caged mussels were exposed to the RE for 90 days (May-July 2005). Mussels were challenged to test their efficiency at eliminating the bacteria, Listonella anguillarium in the bioassay and field studies. The bioassay results showed that higher concentrations of untreated sewage could modulate the immune system of mussels through increased of phagocytic activity (PA), nitric oxide (NO) and hydrogen peroxide (H(2)O(2)) production during 14 days of exposure, and decreased activity and production at 21 days, with the exception of H(2)O(2) production which was high even at 21 days. Mussels exposed to untreated sewage RE also presented a high PA, NO and H(2)O(2) production and lower number of haemocytes compared to mussels from reference sites. In the bacterial challenge, mussels pre-exposed to 100% sewage died 24h after being infected with L. anguillarium, while mussels pre-exposed to 50% eliminated bacteria had a mortality rate of 30%. Mussels from the control, 12.5% and 25% groups eliminated bacteria and no mortality was observed. No significant difference was observed in bacterial clearance in mussels exposed to effluents in the RE. The lesions observed in gills in both studies were: infiltration of haemocytes in the tissue, epithelium proliferation, lamellar fusion and dilated haemolymphatic sinus. In summary, untreated municipal wastewater affected the immune system of blue mussels during 21 days of exposure and the effects were reflected in their capability to resist pathogens. And an immune modulation was observed in mussels exposed to untreated sewage in a RE, but this modulation was not reflected in the mussel's capability in eliminating pathogens.