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Tumor cells may develop alterations in glycosylation patterns during the initial phase of carcinogenesis. These alterations may be important therapeutic targets for lectins with antitumor action. This work aimed to evaluate the in vitro cytotoxicity of VML on tumor and non-tumor cells (concentration of 25 μg/mL and then microdiluted) and evaluate its in vivo toxicity at different concentrations (1.8, 3.5 and 7.0 μg/mL), using Drosophila melanogaster. Toxicity in D. melanogaster evaluated mortality rate, as well as oxidative stress markers (TBARS, iron levels, nitric oxide levels, protein and non-protein thiols). The cytotoxicity assay showed that VML had cytotoxic effect on leukemic lines HL-60 (IC 50  = 3.5 μg/mL), KG1 (IC 50  = 18.6 μg/mL) and K562 (102.0 μg/mL). In the toxicity assay, VML showed no reduction in survival at concentrations of 3.5 and 7.0 μg/mL and did not alter oxidative stress markers at any concentrations tested. Cytotoxicity of VML from HL-60, KG1 and K562 cells could arise from the interaction between the lectin and specific carbohydrates of tumor cells. In contrast, effective concentrations of VML against no-tumor cells human keratinocyte - HaCat and in the D. melanogaster model did not show toxicity, suggesting that VML is a promising molecule in vivo studies involving leukemic cells., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In 2021, our research group published the prominent anticancer activity achieved through the successful combination of two redox centres ( ortho -quinone/ para -quinone or quinone/selenium-containing triazole) through a copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. The combination of two naphthoquinoidal substrates towards a synergetic product was indicated, but not fully explored. Herein, we report the synthesis of 15 new quinone-based derivatives prepared from click chemistry reactions and their subsequent evaluation against nine cancer cell lines and the murine fibroblast line L929. Our strategy was based on the modification of the A-ring of para -naphthoquinones and subsequent conjugation with different ortho -quinoidal moieties. As anticipated, our study identified several compounds with IC 50 values below 0.5 µM in tumour cell lines. Some of the compounds described here also exhibited an excellent selectivity index and low cytotoxicity on L929, the control cell line. The antitumour evaluation of the compounds separately and in their conjugated form proved that the activity is strongly enhanced in the derivatives containing two redox centres. Thus, our study confirms the efficiency of using A-ring functionalized para -quinones coupled with ortho -quinones to obtain a diverse range of two redox centre compounds with potential applications against cancer cell lines. Here as well, it literally takes two for an efficient tango!

The main goal was the development of a polysaccharide microcapsule for anticancer application based on guar gum and sodium alginate for the controlled release of hesperidin and betulinic acid by spray drying technique. The microcapsule showed an Encapsulation Efficiency of 98.15 ± 0.34 % for hesperidin and 99.76 ± 0.22 % for betulinic acid. In the release study, the Korsmeyer-Peppas mathematical model was identified as the most adequate to explain the observed release mechanism. In vivo tests were performed in zebrafish model, revealing that the microcapsules did not alter the locomotor activity and were not toxic within 96 h by oral administration, suggesting their biological safety. In vitro cytotoxic activity against HL-60 cells confirmed an IC 50 value of 2.52 ± 0.23 μg mL -1 in 72 h. Additionally, a decrease in the cytotoxic activity of betulinic acid against L-929 (non-tumor) cells was evidenced. Therefore, the microcapsules synthesized in this work represent a promising formulation for anticancer applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

We synthesized ten enamine naphthoquinones with yields ranging from 43 to 76%. These compounds were screened for their in vitro antiproliferative activities by MTT assay against four types of human cancer cell lines: HCT116, PC3, HL60 and SNB19. The naphthoquinones bearing the picolylamine (7) and quinoline (12) moieties were the most actives (IC 50  < 24 μM for all the cell lines), which were comparable or better to the values obtained for the control drugs. In silico evaluations allowed us to develop a qualitative Structure-Activity Relationship which suggest that electrostatic features, particularly the C 2 -C 3 internuclear repulsion and the molecular dipole moment, relate to the biological response. Furthermore, Molecular Docking simulations indicate that the synthetic compounds have the potential to act as anticancer molecules by inhibiting topoisomerase-II and thymidylate synthase., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

We report the synthesis of 47 new quinone-based derivatives via click chemistry and their subsequent evaluation against cancer cell lines and the control L929 murine fibroblast cell line. These compounds combine two redox centers, such as an ortho -quinone/ para -quinone or quinones/selenium with the 1,2,3-triazole nucleus. Several of these compounds present IC 50 values below 0.5 μM in cancer cell lines with significantly lower cytotoxicity in the control cell line L929 and good selectivity index. Hence, our study confirms the use of a complete and very diverse range of quinone compounds with potential application against certain cancer cell lines., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Double ruthenium(II)-catalyzed alkyne annulations of quinones were accomplished. Thus, a strategy is reported that provides step-economical access to valuable quinones with a wide range of applications. C-H/N-H activations for alkyne annulations of naphthoquinones provided challenging polycyclic quinoidal compounds by forming four new bonds in one step. The singular power of the thus-obtained compounds was reflected by their antileukemic activity., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The benthic biodiversity of the abyssal Labrador Sea was investigated using Agassiz trawl and in situ imagery. A megafaunal scaphopod associated with an epizoic anemone was recovered from soft sediments. Morphological and molecular investigations revealed the scaphopod to be an undescribed species in the dentaliid genus Fissidentalium P. Fischer, 1885. The new scaphopod species is characterised by a large size for the genus, is moderately curved, with numerous narrow, longitudinal ribs (60 ribs at 11 mm diameter ventral aperture), a dentaliid radula, and is described herein as Fissidentalium aurae sp. nov. The new species shows a close genetic relationship to congeners of Fissidentalium and separates from the sister genera Dentalium Linnaeus, 1758 and Antalis H. Adams & A. Adams, 1854. Genetic COI barcoding of the epizoic anemone suggests the species is a member of the family Actinostolidae Carlgren, 1932. The discovered association of a burrowing scaphopod with an epifaunal anemone at abyssal depth is a new record for the region and is indicative of how little is known about symbioses in the deep sea. [ABSTRACT FROM AUTHOR]

Environmental certificates in aquaculture are becoming important market tools throughout the world. However, there are important regional and national differences, and Brazil, due to the low number of certified companies, deserves specific research. A preliminary analysis of the Brazilian aquaculture market shows a large market with strong growth and more than 25 cultivated species, but where 80% of the turnover is focused on tilapia, tambaqui, and white shrimp, primarily targeting the domestic market with very few exceptions to the external market. These particular conditions seem to explain the low number of certified aquaculture companies, even when compared to other countries in the region with similar or smaller aquaculture industries. This study interviewed managers from 80 companies in the Brazilian aquaculture production chain, including all certified companies. The results seem to be in line with previous studies conducted in different parts of the world. The main benefits associated with aquaculture certifications are access to new markets and production improvement, while the main barriers to certification are high costs, lack of awareness, bureaucracy, or lack of government support. Certified Brazilian aquaculture companies share similar characteristics among themselves but differ from most companies in Brazil; they are all large-scale firms, mainly related to tilapia production and oriented towards the international market. The low number of certified companies seems to be linked to the large demand for aquatic products in Brazil that even Brazilian aquaculture firms cannot satisfy. [ABSTRACT FROM AUTHOR]

Hesperidin (Hsd), a bioactive phytomedicine, experienced an antidiabetic activity versus both Type 1 and Type 2 Diabetes mellitus. However, its intrinsic poor solubility and bioavailability is a key challenging obstacle reflecting its oral delivery. From such perspective, the purpose of the current study was to prepare and evaluate Hsd-loaded sulfobutylether-β-cyclodextrin/chitosan nanoparticles (Hsd/CD/CS NPs) for improving the hypoglycemic activity of the orally administered Hsd. Hsd was first complexed with sulfobutylether-β-cyclodextrin (SBE-β-CD) and the complex (CX) was found to be formed with percent complexation efficiency and percent process efficiency of 50.53 ± 1.46 and 84.52 ± 3.16%, respectively. Also, solid state characterization of the complex ensured the inclusion of Hsd inside the cavity of SBE-β-CD. Then, Hsd/CD/CS NPs were prepared using the ionic gelation technique. The prepared NPs were fully characterized to select the most promising one (F1) with a homogenous particle size of 455.7 ± 9.04 nm, a positive zeta potential of + 32.28 ± 1.12 mV, and an entrapment efficiency of 77.46 ± 0.39%. The optimal formula (F1) was subjected to further investigation of in vitro release, ex vivo intestinal permeation, stability, cytotoxicity, and in vivo hypoglycemic activity. The results of the release and permeation studies of F1 manifested a modulated pattern between Hsd and CX. The preferential stability of F1 was observed at 4 ± 1 °C. Also, the biocompatibility of F1 with oral epithelial cell line (OEC) was retained up to a concentration of 100 µg/mL. After oral administration of F1, a noteworthy synergistic hypoglycemic effect was recorded with decreased blood glucose level until the end of the experiment. In conclusion, Hsd/CD/CS NPs could be regarded as a hopeful oral delivery system of Hsd with enhanced antidiabetic activity. [ABSTRACT FROM AUTHOR]

Located 1140 km from the South American coastline in the South Atlantic Ocean and with an age of 4 million years, Trindade Island is the most recent volcanic component of Brazilian territory. Its original native vegetation has been severely damaged by human influence, in particular through the introduction of exotic grazing animals such as goats. However, since the complete eradication of goats and other feral animals in the late 1990s, the island's vegetation has been recovering, and even some endemic species that had been considered extinct have been rediscovered. In this study, we set out to characterize the contemporary cryptic diversity in soils of the recovering native forest of Trindade Island using metabarcoding by high throughput sequencing (HTS). The sequence diversity obtained was dominated by microorganisms, including three domains (Bacteria, Archaea, and Eukarya) and five kingdoms (Fungi, Metazoa, Protozoa, Chromista, and Viridiplantae). Bacteria were represented by 20 phyla and 116 taxa, with Archaea by only one taxon. Fungi were represented by seven phyla and 250 taxa, Viridiplantae by five phyla and six taxa, Protozoa by five phyla and six taxa, Metazoa by three phyla and four taxa and Chromista by two phyla and two taxa. Even after the considerable anthropogenic impacts and devastation of the island's natural forest, our sequence data reveal the presence of a rich and complex diversity of microorganisms, invertebrates, and plants and provide important baseline biodiversity information that will contribute to ecological restoration efforts on the island. [ABSTRACT FROM AUTHOR]

Coastal zones support the most productive marine ecosystems, yet they are increasingly threatened by anthropogenic stressors such as dredging. In this study, we investigated how seasonal variation and dredging activities conducted during the construction of a harbor and submarine base (Sepetiba Bay, RJ, Brazil) affected the phytoplankton and zooplankton assemblages. The observed temporal variability at five different sites over 10 years revealed that dredging exceeds the expected influence of dry and rainy seasons on plankton abundance and diversity. In general, the abundance of both groups increased during dredging due to the resuspension of nutrients and benthic organisms. This increase was particularly evident in the dinoflagellate Scrippsiellaa cuminata, the diatoms Thalassiosira rotula and Nitzschia longissima, and the herbivorous zooplankton Acartia clausii and Pseudevadne tergestina. Moreover, season and dredging activities synergistically influenced plankton assemblages, resulting in larger seasonal variations during dredging activities. After the end of the harbor construction, plankton abundance decreased and remained low until the end of the monitoring, which may indicate persistent changes in the biodiversity and ecosystem functioning of impacted areas. [ABSTRACT FROM AUTHOR]

The expression 'you need to know to conserve' is a well-known cliche among biologists. Documenting the richness of a group of organisms is the first step towards understanding biodiversity and preparing efficient conservation plans. In this context, many efforts have been made to quantify the number of species on Earth and estimate the number of species still unknown to science. A few countries have complete and integrated databases estimating the approximate number of species recorded for their territory, particularly in the Global South. In Brazil, a country of continental dimensions, revealing the richness of the second most diverse clade of invertebrates (=Mollusca) has been a goal of taxonomists. Recently, in an unprecedented, collective, and integrated effort among Brazilian malacologists, it was possible to estimate how many valid species of molluscs are there in Brazil. In this effort, more than 30 mollusc experts joined together to update the Taxonomic Catalogue of the Brazilian Fauna (TCBF), a governmental website that allows a quick and real-time updating of all Metazoan. So far, more than 5,000 updates have been made in TCBF, indicating the presence of 3,552 valid species of molluscs in Brazil, distributed among the main clades as follows: Caudofoveata (10 spp.), Solenogastres (6 spp.), Polyplacophora (35 spp.), Scaphopoda (43 spp.), Cephalopoda (92 spp.), Bivalvia (629 spp.) and Gastropoda (2,737 spp.). The present study, in addition to demonstrating for the first time the richness of Brazilian molluscs, also presents the state of the art of this important phylum of invertebrates highlighting its most representative and neglected groups. [ABSTRACT FROM AUTHOR]

Trindade Island, Brazil, is a small, remote volcanic island located 1140 km off the coast of southeastern Brazil. The green turtle (Chelonia mydas) nesting aggregation on Trindade is genetically distinct, the largest in the southwest Atlantic, and represents the southern limit of green turtle nesting in the Atlantic. Projeto TAMAR (a Brazilian conservation program) has monitored the nesting aggregation discontinuously since 1982. In 2009, a standardized protocol was established for the two beaches (Andradas and Tartarugas) with the highest nest abundance. Data from December 2009 through April 2017 (except 2013) were used in this study. Annual numbers of tracks left by females that emerged onto the beach vary between 558 and 3317 tracks for Andradas and between 760 and 3559 tracks for Tartarugas. Mean nesting probabilities (probability that an emerging female deposits eggs) for all years were 0.22 (95% HDI (highest posterior density interval) = 0.14–0.30) for Andradas and 0.45 (95% HDI = 0.37–0.53) for Tartarugas. Nesting probabilities varied among and within years and had a negative relationship with daily track counts. During our study, annual estimates of nests were stable on both Andradas (range 38–2001) and Tartarugas (range 248–2769). Nest abundance estimates between 1991 and 2008 from an earlier study indicated a stable population, extending the duration of apparent stability to 26 years with the caveat that the studies used different estimation methods. This stability is in contrast with the increasing trends for most green turtle nesting aggregations in the Atlantic. [ABSTRACT FROM AUTHOR]

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Individual variability within a population and the eventual repeatability across time and space may provide stability in a population facing environmental changes, by affecting individuals differently. Thus, the variability and repeatability of behaviours, habitats used, niches and migratory pathways could play an important role. Trindade petrels (Pterodroma arminjoniana) are threatened seabirds that breed year round on Trindade Island in the South Atlantic Ocean, migrate to North Atlantic Ocean in the non-breeding periods, and use wide oceanic areas. This study investigated the timing, at-sea distribution, and trophic niche throughout the annual cycle of the austral fall/winter breeding group of Trindade petrel and examined consistency in distribution and trophic niche used by the Trindade petrel at the individual level, in different breeding seasons, using geolocator tracking and stable isotope analysis. Results demonstrated that petrels breed annually, maintaining their breeding schedules. Petrels share a common, vast oligotrophic oceanic area during both breeding and non-breeding periods inside the South Atlantic and North Atlantic Subtropical Gyres, respectively. Two migratory patterns were identified and used repeatedly by individuals. Although petrels overlapped at-sea distributions in consecutive breeding seasons, consistency in parameters tested was not found. Breeding in two schedules along the year, in addition to the use of different migratory pathways and flexibility in their isotopic niche can be an advantage for Trindade petrel population to cope with environmental changes. Causes and consequences of variable niche and pathways used, and the existence of consistency and variability among birds breeding later on the year remain poorly-known. [ABSTRACT FROM AUTHOR]

The objective of this research is to investigate the pollution levels of tin (Sn), arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), mercury (Hg), and zinc (Zn) of soil/sediment taken in Coles Bay Area (CBA), Svalbard, and Great Bay Area (GBA), China, in an attempt to evaluate the pollution potential related to recent development in the areas. A total of 150 soil/sediment samples were collected in each location. Heavy metal concentrations were detectable levels at all sites and the values of Cd of all soil/sediment samples were higher than Dutch Target and Intervention Values. Heavy metal concentration in soil/sediment was further analyzed by principal component analysis (PCA). It was revealed that three components were found in two studying sites and contributed 60.2% and 75.9% of variations to reflect soil/sediment quality in CBA and GBA, respectively. Based on the results of KMO (0.52) and Bartlett's test (p < 0.000), there are 32.1%, 15.6%, and 11.1% and 39.45%, 19.01%, and 17.52% of the variance in the first, second, and third component explained that the metal concentration of Pb, Cd, and Sn was highly correlated with the soil/sediment quality in CBA and GBA, respectively. Among these three heavy metals, Cd concentration was the common dominant factor to affect soil/sediment quality in these two study sites. It is recommended that investigation of the sources of pollution (either point or non-point source) during CBA or GBA development and management together with consideration of abiotic (soil)-biotic (organisms) interactions should be taken into account when choosing suitable remediation strategies in the future. [ABSTRACT FROM AUTHOR]

Intraspecific plumage polymorphism in seabirds is often attributed to advantages in foraging activities and escape from predators, but its role in sexual selection is not well understood. The Trindade petrel (Pterodroma arminjoniana) presents morphs varying from pale to whole dark, with no apparent sexual size dimorphism (SSD). We tested assortative mating in Trindade petrels based on plumage colours and body size. In addition, genders of Trindade petrels were identified molecularly aiming to test SSD based on morphometrics, which was also used to generate a discriminant function for sex assignment. Within-pair consistency in plumage colour (i.e. birds paired with mates of the same morph) was detected in 9 out of 10 pairs, but not in morphometric traits. Minimum bill depth and bill depth at unguis were traits significantly larger in males. The best model was adjusted with Bill depth at unguis, wing chord and body mass, with global discriminatory power of 78.4%. Our results suggest that plumage colours may be sexually selected in Trindade petrels, which brings evolutionary implications on the persistence of plumage polymorphism. Discriminatory power of the best discriminant function was similar to those found in other Procellariiformes and also among datasets obtained by distinct researchers, demonstrating its robustness. [ABSTRACT FROM AUTHOR]

Poecilia vivipara, a small euryhaline guppy is reported at the Maceió River micro-basin in the Fernando de Noronha oceanic archipelago, northeast Brazil. However, the origin (human-mediated or natural dispersal) of this insular population is still controversial. The present study investigates how this population is phylogenetically related to the surrounding continental populations using the cytochrome oxidase I mitochondrial gene from eleven river basins in South America. Our phylogenetic reconstruction showed a clear geographical distribution arrangement of P. vivipara lineages. The Fernando de Noronha haplotype fell within the 'north' clade, closely related to a shared haplotype between the Paraíba do Norte and Potengi basins; the geographically closest continental drainages. Our phylogenetic reconstruction also showed highly divergent lineages, suggesting that P. vivipara may represent a species complex along its wide distribution. Regarding to the insular population, P. vivipara may have been intentionally introduced to the archipelago for the purpose of mosquito larvae control during the occupation of a U.S. military base following World War II. However, given the euryhaline capacity of P. vivipara, a potential scenario of natural (passive or active) dispersal cannot be ruled out. [ABSTRACT FROM AUTHOR]

The current conservation status of the bottlenose dolphin (Tursiops truncatus) under the IUCN is ‘least concern’. However, in the Caribbean, small and localized populations of the ‘inshore form’ may be at higher risk of extinction than the ‘worldwide distributed form’ due to a combination of factors including small population size, high site fidelity, genetic isolation, and range overlap with human activities. Here, we study the population genetic structure of bottlenose dolphins from the Archipelago of Bocas del Toro in Panama. This is a small population characterized by high site fidelity and is currently heavily-impacted by the local dolphin-watching industry. We collected skin tissue samples from 25 dolphins to study the genetic diversity and structure of this population. We amplified a portion of the mitochondrial Control Region (mtDNA-CR) and nine microsatellite loci. The mtDNA-CR analyses revealed that dolphins in Bocas del Toro belong to the ‘inshore form’, grouped with the Bahamas-Colombia-Cuba-Mexico population unit. They also possess a unique haplotype new for the Caribbean. The microsatellite data indicated that the Bocas del Toro dolphin population is highly structured, likely due to restricted movement patterns. Previous abundance estimates obtained with mark-recapture methods reported a small population of 80 dolphins (95% CI = 72–87), which is similar to the contemporary effective population size estimated in this study (Ne = 73 individuals; CI = 18.0 - ∞; 0.05). The combination of small population size, high degree of genetic isolation, and intense daily interactions with dolphin-watching boats puts the Bocas del Toro dolphin to at high risk of extinction. Despite national guidelines to regulate the dolphin-watching industry in Bocas del Toro and ongoing educational programs for tour operators, only in 2012 seven animals have died due to boat collisions. Our results suggest that the conservation status of bottlenose dolphins in Bocas del Toro should be elevated to ‘endangered’ at the national level, as a precautionary measure while population and viability estimates are conducted. [ABSTRACT FROM AUTHOR]

Seabirds breeding in tropical environments experience high energetic demands, when foraging in an oligotrophic environment. The globally threatened Trindade petrel Pterodroma arminjoniana has its largest colony in Trindade Island (20°30′S-29°19′W) inside the oligotrophic South Atlantic Subtropical Gyre. Diet sampling methods, geolocator tracking and stable isotope analysis were used to describe its diet, compare foraging trips and distributions, and assess temporal variations in the trophic niche throughout the breeding period. Diet consisted mainly of squid and fish. The high species diversity and wide range of prey sizes consumed suggests the use of multiple foraging techniques. Stable isotope mixing models confirm that Trindade petrels rely mainly on squid throughout the breeding period. Its broad isotopic niche seems to reflect both a diverse diet and foraging range, since birds can reach up to 3335 km from the colony. Isotopic niche showed limited variation even in an 8-year interval, apparently due to oceanographic stability, although changes in the isotopic niche have demonstrated an adjustment to different conditions in different seasons. Petrels change foraging areas and prey during the breeding period: pre-incubating birds use more productive areas west of Trindade Island and obtain low trophic position prey; incubating petrels perform longer trips southward to consume prey of high trophic position; and chick-rearing petrels use areas around the island. These results demonstrate that to deal with high demand breeding in a colony surrounded by oligotrophic waters, Trindade petrels need to explore wide foraging areas and utilize a diverse diet, besides adjusting trophic niche according to breeding stage. [ABSTRACT FROM AUTHOR]

The radular morphology ofZidona dufresneiwas studied by optical and scanning electron microscopy. We analysed the variability among and within three populations distributed along the southwestern Atlantic Ocean coast, considering the hypothesis that the isolation among populations favours adaptive phenotypic variation, which is also expressed at the radular level. Populations selected for this study differ in their maximum individual size, growth rate, size and age at maturity, and fecundity. This study provides the first analysis of the interpopulational variability of the radula ofZidona dufresneiand the first description of its morphology.Zidonia dufresneiexhibited a rachiglossate radulae composed of rows of tricuspid teeth (radular formula: 0+R+0). No differences in tooth shape among populations and sexes were observed. However, significant interpopulational differences in the height of the rachidian cusp and total length of the radula were detected. Specimens from San Antonio Bay showed the lowest values for all radular variables. Positive significant relationships between total shell length and the height of the rachidian cusp and total length of the radula were found, while the number of rows remained relatively constant regardless of size. The larger morphotypes had a longer radula because of an increase in the height of the rachidian cusp. No sexual dimorphism was observed in any morphometric variables of the radula. The results suggest that populations distributed along the Argentine Sea are homogeneous for radular morphology, despite the differences in life history traits, which may be linked to a similarity in feeding habits across populations. [ABSTRACT FROM PUBLISHER]

In this article, a study of the Al(+3) interactions in acidic waters with biomass of different edible seaweeds: brown ( Fucus vesiculosus, Saccorhiza polyschides), red ( Mastocarpus stellatus, Gelidium sesquipedale, Chondrus crispus), and green ( Ulva rigida, Codium tomentosum), has been performed. The influence of both, the initial concentration of metal and the solution pH, on the Al-uptake capacity of the biomass has been analyzed. From preliminary tests, species Fucus vesiculosus and Gelidium sesquipedale have been selected for a more exhaustive analysis. Sorption kinetic studies demonstrated that 60 min are enough to reach equilibrium. The intraparticle diffusion model has been used to describe kinetic data. Equilibrium studies have been carried out at pH values of 1, 2.5, and 4. Langmuir isotherms showed that the best uptake values, obtained at pH 4, were 33 mg/g for F. vesiculosus and 9.2 mg/g for G. sesquipedale. These edible seaweeds have been found particularly effective in binding aluminum metal ions for most of the conditions tested. Physicochemical data reported at these low pH values could be of interest, not only in modeling aluminum-containing antacids-food pharmacokinetic processes produced in the stomach (pH values 1 to 3) but in remediation studies in acidic waters. Practical Application: Aluminum is thought to be linked to neurological disruptions such as Alzheimer's disease. In this article, the adsorption ability of different types of edible seaweeds toward aluminum has been studied. The choice of low pH values is due to the fact that stomach region is acidic with a pH value between 1 and 3 as a consequence of hydrochloric secretion; so physicochemical data reported in this study could be of interest in modeling drug-food interactions, in particular those referring to aluminum-containing antacids-food pharmacokinetic processes produced in the gastrointestinal tract. [ABSTRACT FROM AUTHOR]

Among the diverse patterns of energy allocation to the offspring of gastropods, the presence of egg capsules to protect embryos is common. Females of the edible snail Zidona dufresnei attach egg capsules to hard substrates in shallow Argentine Patagonian waters (40°45′S, 64°56′W) during spring-summer. Embryonic development takes about 30 days at 22°C. In this study, three likely capsule predator species and the marks left by each on egg capsule walls were identified in laboratory experiments in February 2010. Abundances of predators and egg capsules with evidence of predation were assessed in the field in the summers of 2010 and 2011. Under laboratory conditions ( N = 10 replicates per treatment and control), the predation rate by the chiton Chaetopleura isabellei was the highest (up to 90%), followed by the gastropod Tegula patagonica and the crab Neohelice granulata (~20% each). Nearly 60% of 41 capsules found in the field showed signs of predation. According to the marks identified in the laboratory, C. isabellei was responsible for 79% of this predation, and T. patagonica for the rest. Predation appears to be important during the encapsulated early life and could be an agent for selecting for resistant capsule walls and a relatively shorter development time. [ABSTRACT FROM AUTHOR]

Historical records suggest that the petrels of Round Island (near Mauritius, Indian Ocean) represent a recent, long-distance colonization by species originating from the Atlantic and Pacific Oceans. The majority of petrels on Round Island appear most similar to Pterodroma arminjoniana, a species whose only other breeding locality is Trindade Island in the South Atlantic . Using nine microsatellite loci, patterns of genetic differentiation in petrels from Round and Trindade Islands were analysed. The two populations exhibit low but significant levels of differentiation in allele frequencies and estimates of migration rate between islands using genetic data are also low, supporting the hypothesis that these populations have recently separated but are now isolated from one another. A second population of petrels, most similar in appearance to the Pacific species P. neglecta, is also present on Round Island and observations suggest that the two petrel species are hybridizing. Vocalizations recorded on the island also suggest that hybrid birds may be present within the population. Data from microsatellite genotypes support this hypothesis and indicate that there may have been many generations of hybridization and back-crossing between P. arminjoniana and P. neglecta on Round Island. Our results provide an insight into the processes of dispersal and the consequences of secondary contact in Procellariiformes. [ABSTRACT FROM AUTHOR]

The edible volutid snail Adelomelon ancilla occurs on the Argentine coast and may have the capacity to serve as source of support for local fisheries. However, knowledge of its reproduction is lacking. Over 3 years (from September 2000 to July 2004) we studied the oviposition at Golfo Nuevo, Patagonia by diving. Monthly collections were performed to examine gonadal stages histologically during 2002–2003. Gamete development stages corresponded with the expected period for oviposition occurring from July to November, a time of increasing day length. Oviposition also took place in March when water temperature attained a maximum of 18°C. Following the spawning period, remaining gametes were resorpted in both sexes. Males contained sperm throughout the year, parasperm and eusperm forms were found within the same acinus. Oogonia/oocytes ranged from 20 to 240 μm in diameter during oogenesis. Females commenced laying egg capsules from a shell length of 114 mm. Reproduction is compared with other fishable volutid snails from the Argentine shelf, and suggests the need to apply certain fishing restrictions if the resource begins to be utilized commercially. The imposex condition was found in snails from some shipping areas. The frequency of this condition declined with distance from the port. [ABSTRACT FROM AUTHOR]

Stable isotopes of growing feathers and blood both represent assimilated diet, and both tissues are used to study the diet and foraging distribution of marine and terrestrial birds. Although most studies have assumed that both tissues represent a difference of one trophic level to diet, the enrichment factors of blood and feathers may differ, especially where endogenous reserves are used as precursors during feather synthesis. In this study, we compare carbon and nitrogen stable isotopes of blood and simultaneously growing feathers of five species of Procellariiformes, representing five genera, different geographical regions and different life stages (chicks and adults). In all species, feathers were enriched in 15N and 13C compared with blood. Isotopic values of carbon and nitrogen were correlated in different tissues growing simultaneously for most species analyzed, suggesting that mathematical corrections could be used to compare different tissues. Our results imply that more care needs to be taken when comparing stable isotope signatures across studies assuming different tissues are equivalent indicators of trophic ecology. [ABSTRACT FROM AUTHOR]

Members of Odontocymbiola magellanica (Volutidae, Odontocymbiolinae) inhabit Argentinean waters from 35°S to the Magallanes Strait. The reproductive biology of this potential fishery resource has not been studied before. Male individuals reach maturity at 80 mm and females at 90 mm, corresponding to ∼7 and 8 years of age, respectively. Mating was observed in the field in all seasons and females possess live spermatozoa in the bursa copulatrix all year round, suggesting that living sperm can be preserved for several months. Major oviposition events occurred July (winter) to December (summer) during the 5 years sampled, as characterized by aggregation of females coincident with increasing photoperiod from winter to summer solstices, and not, apparently, by increase in water temperature. Males showed gametogenic activity throughout the year. Gamete resorption occurred in both sexes. Ultrastructural studies showed that oocytes are attached to companion cells, which enables cell–cell communication and provides support until evacuation; males showed normal sperm cells and two types of parasperms. If populations of O. magellanica are commercially exploited in the future, we propose a minimum catch size of 100 mm, and a ban on the collection of females and egg capsules during the reproductive season. [ABSTRACT FROM AUTHOR]

Growth, age and somatic production of the benthic predator Odontocymbiola magellanica were studied in Golfo Nuevo (42°S 65°W), on the South American Atlantic shelf. Stable oxygen isotope ratios confirmed semiannual formation of internal and external shell growth marks. Mean shell length (SL) of females was 115 and 112 mm for males, while population modal shell-free wet mass (SFWM) was 62.8 g. A Gompertz growth function (SL∞ = 200 mm, K = 0.197, t 0 = 5.486) fitted 113 pairs of size-at-age data (12 shells) best. O. magellanica is a long-lived species, reaching up to 20 years of age. The maximum individual somatic production of 29.3 g SFWM per year is attained at 145 mm SL, which corresponds to about 12 years of age. The life span of this volutid seems to be twice compared with other large gastropods. O. magellanica is a valuable and exploitable resource regarding its large size and somatic production, but on the other hand, its slow growth, late maturity and direct development makes it extremely vulnerable to overexploitation. [ABSTRACT FROM AUTHOR]

Growth, age and somatic production of the benthic predator Adelomelon brasiliana were studied at the southern limit of its distribution on the South American Atlantic shelf. Stable oxygen isotope ratios confirmed annual formation of internal shell growth marks. Modal shell length of the population was 140 mm, while modal shell-free wet mass was 255 g. A logistics growth function (SL∞=186.28 mm, K=0.185, t0=4.601) fitted 131 pairs of size-at-age data (25 shells) best. A. brasiliana is a very long-lived species, reaching up to 20 years of age. The maximum individual somatic production of 46 g shell-free wet mass year−1 is attained at 145 mm shell length, which corresponds to about 12 years of age. [ABSTRACT FROM AUTHOR]

The reproductive season of the Adelomelon brasiliana population of Mar del Plata extends from September to April (austral spring and summer), showing synchronisation with water temperature. Adult gonad state is related to shell-free wet mass. Oocytes reach 200 μm in diameter before spawning. In autumn, a resting phase begins, when no new oocytes develop and the non-spawned ones undergo reabsorption. Gonadic development begins during the early winter, when new previtellogenic oocytes can be observed through histology. The long reproductive season would increase the ability of the species to recover from harvesting. [ABSTRACT FROM AUTHOR]

Compares the frequency of occurrence of pelagic versus benthic development of prosorobranch gastropods along two latitudinal gradients of South America based on Thorson's rule on marine invertebrates. Background on Thorson's rule; Impact of the physical history of the coast and water on the development of gastropods; Factors contributing to the differences in developmental modes of gastropods.

Among the diverse patterns of energy allocation to the offspring of gastropods, the presence of egg capsules to protect embryos is common. Females of the edible snail Zidonadufresnei attach egg capsules to hard substrates in shallow Argentine Patagonian waters (40°45'S, 64°56'W) during spring-summer. Embryonic development takes about 30 days at 22°C. In this study, three likely capsule predator species and the marks left by each on egg capsule walls were identified in laboratory experiments in February 2010. Abundances of predators and egg capsules with evidence of predation were assessed in the field in the summers of 2010 and 2011. Under laboratory conditions (N = 10 replicates per treatment and control), the predation rate by the chiton Chaetopleuraisabellei was the highest (up to 90%), followed by the gastropod Tegulapatagonica and the crab Neohelicegranulata (~20% each). Nearly 60% of 41 capsules found in the field showed signs of predation. According to the marks identified in the laboratory, C. isabellei was responsible for 79% of this predation, and T. patagonica for the rest. Predation appears to be important during the encapsulated early life and could be an agent for selecting for resistant capsule walls and a relatively shorter development time., Author(s): Andrea Roche [sup.1] , Matías Maggioni [sup.1] , Maite Narvarte [sup.1] [sup.2] Author Affiliations: (1) grid.412234.2, 000000012112473X, Instituto de Biología Marina y Pesquera Almirante Storni e Instituto Multidisciplinario de [...]