Role of UV radiation and oxidation on polyethylene micro- and nanoplastics: impacts on cadmium sorption, bioaccumulation, and toxicity in fish intestinal cells.

This study investigated the role of ultraviolet (UV) radiation and oxidation in high-density polyethylene microplastics (2-15 μm) and nanoplastics (0.2-9.9 μm) (NMPs) on particle chemistry, morphology, and reactivity with cadmium (Cd).

Comparative assessment of microplastics and microalgae as vectors of mercury and chlorpyrifos in the copepod Acartia tonsa.

Microplastics (MPs) raise concerns not only as pollutants themselves, but also due to their ability to act as vectors of pollutants adsorbed from seawater, transferring them to marine organisms. However, the relevance of MPs as carriers of pollutants compared to microalgae needs further exploration. This study compared the role of MPs (2-10 μm non-oxidized and 10-15 μm oxidized high-density polyethylene) and natural organic particles (Rhodomonas lens microalgae, MA) as carriers of mercury (Hg, 2.

Rational synthesis of total damage during cryoprotectant equilibration: modelling and experimental validation of osmomechanical, temperature, and cytotoxic damage in sea urchin () oocytes.

Sea urchins (, ) are important for both aquaculture and as model species. Despite their importance, biobanking of urchin oocytes by cryopreservation is currently not possible. Optimized cryoprotectant loading may enable novel vitrification methods and thus successful cryopreservation of oocytes.

The Importance of Developing and Standardizing Gamete, Embryo and Larvae Handling in Aquatic Animals.

Artificial reproduction in aquatic animals usually involves the collection and handling of gametes both from males and females in a way that secures their quality and optimizes the fertilization event [...

Handling, Reproducing and Cryopreserving Five European Sea Urchins (Echinodermata, Klein, 1778) for Biodiversity Conservation Purposes.

In this work, five local sea urchin species found in European waters were studied. Four were regular species: , , (Linnaeus, 1758) and the edible sea urchin ; and one was an irregular species, . These five species of sea urchins have been studied regarding their fertility, toxicity of cryoprotecting agents, cryopreservation of different cell types and chilling injury.

Influence of microplastics on the toxicity of chlorpyrifos and mercury on the marine microalgae Rhodomonas lens.

The growing use of plastics, including microplastics (MPs), has enhanced their potential release into aquatic environments, where microalgae represent the basis of food webs. Due to their physicochemical properties, MPs may act as carriers of organic and inorganic pollutants. The present study aimed to determine the toxicity of polyethylene MPs (plain and oxidized) and the model pollutants chlorpyrifos (CPF) and mercury (Hg) on the red microalgae Rhodomonas lens, to contribute to the understanding of the effects of MPs and associated pollutants on marine ecosystems, including the role of MPs as vectors of potentially harmful pollutants to marine food webs.

Development of a method to cryopreserve Greenshell mussel™ (Perna canaliculus) veliger larvae.

Cryopreservation of larvae of Greenshell™ mussel Perna canaliculus, the most cultivated species in New Zealand, can provide flexibility for selective breeding programmes and enhance its global production. In this study, we set out to develop a reliable protocol for freezing D-stage larvae of Greenshell™ mussels that ensured long-term survival for successful rearing of thawed larvae in the hatchery. The effects of different combinations of cryoprotecting agents (CPA), varying CPA equilibration times, larval concentrations per straw as well as different larval development stages (48 h vs 72 h old) were evaluated by assessing the behavioural response (swimming activity, algal consumption), shell size and survival of larvae, up to 4 days post-thawing.

Cryopreservation of Algae.

Cryopreservation has been successfully used in the banking and maintenance of cultures of microorganisms, from bacteria to yeasts, since the onset of cryobiology. Biobanking of marine biological resources is crucial for development of scientific knowledge as researchers rely on guaranteed access to reliable, stable resources. Culture collections play a key role in the provision of marine biological resources as they ensure long-term ex situ storage of biological resources that are made available for public and private sector research and education.

Cryopreservation of Marine Invertebrates: From Sperm to Complex Larval Stages.

Marine invertebrates represent the vast majority of marine biodiversity; they are extremely diverse playing a key role in marine ecosystems, thus playing an important role at the socioeconomic level. Some invertebrates such as sea urchins, ascidians, and horse-shoe crabs are very well-known model organisms for research and biocompound discovery. In this chapter we revisit the importance of cryopreservation for the conservation and rational use in research, fisheries management, or aquaculture and provide comprehensive protocols for the cryopreservation of sperm, embryos, and larvae.

First steps towards Echinometra lucunter embryo cryopreservation.

We have studied the sensitivity to cryoprotecting agents of different embryos of the local sea urchin, Echinometra lucunter which is the species used for embryo-larval bioassays in Brazil. We have located significant differences between both species sensitivity to cryoprotecting agents; while for P. lividus propylene glycol was the less toxic compound for most development stages, whereas for E.

A preliminary study of osmotic dehydration in zebrafish embryos: Implications for vitrification and ultra-fast laser warming.

To date, traditional cryopreservation techniques have not been amenable to zebrafish (Danio rerio) embryos, due in part to their large yolky eggs, which have a low surface to volume ratio and limited permeability to water and cryoprotectants. However, recent vitrification and ultra-rapid warming studies in mice have demonstrated successful preservation by dehydrating 85% or more of their total water content. We hypothesized that this approach may help overcome the barriers to embryo cryopreservation among D.

Intracellular ice formation in mouse zygotes and early morulae vs. cooling rate and temperature-experimental vs. theory.

In this study, mature female mice of the ICR strain were induced to superovultate, mated, and collected at either zygote or early morula stages. Embryos suspended in 1 M ethylene glycol in PBS containing 10 mg/L Snomax for 15 min, then transferred in sample holder to Linkam cryostage, cooled to and seeded at 7 °C, and then observed and photographed while being cooled to -70 °C at 0.5-20 °C/min.

Roles of intracellular ice formation, vitrification of cell water, and recrystallisation of intracellular ice on the survival of mouse embryos and oocytes.

Mazur and collaborators began examining the validity of initial views regarding mouse oocyte and embryo vitrification and found that most are partially or fully wrong. First, the relative effects of warming and cooling rates on the survival of mouse oocytes subjected to a vitrification procedure were determined. The high sensitivity to warming rate strongly suggests that the lethality of slow warming is a consequence of either the crystallisation of intracellular glassy water during warming or the recrystallisation during slow warming of small intracellular crystals that had formed during cooling.

The survival of mouse oocytes shows little or no correlation with the vitrification or freezing of the external medium, but the ability of the medium to vitrify is affected by its solute concentration and by the cooling rate.

As survival of mouse oocytes subjected to vitrification depends far more on the warming rate than on the cooling rate, we wished to determine whether the lack of correlation between survival and cooling rate was mirrored by a lack of correlation between cooling rate and vitrification of the medium (EAFS), and between survival and the vitrification of the medium. The morphological and functional survival of the oocytes showed little or no relation to whether or not the EAFS medium vitrified or froze. We studied if the droplet size and the elapsed time (between placing the droplet on the Cryotop and the start of cooling) affects the result through modification of the cooling rate and solute concentration.

Advances in the cryopreservation of sea-urchin embryos: Potential application in marine water quality assessment.

Among the most widely used biological techniques in marine pollution assessment, the sea-urchin embryo-larval bioassay is in an advanced developmental stage. Cryopreservation might help to overcome the problem of the spawning seasonality and therefore strengthen the use of those embryo-larval bioassays. This work investigates different factors influencing cryopreservation of sea-urchin embryos, including the cooling rates and holding temperatures, the seeding, or the impact of plunging into liquid nitrogen.

Cryopreservation of sea urchin embryos (Paracentrotus lividus) applied to marine ecotoxicological studies.

Current strategies for marine pollution monitoring are based on the integration of chemical and biological techniques. The sea urchin embryo-larval bioassays are among the biological methods most widely used worldwide. Cryopreservation of early embryos of sea urchins could provide a useful tool to overcome one of the main limitations of such bioassays, the availability of high quality biological material all year round.