Lanan (1971) working on oyster sperm and Asahina and Takahashi (1977) on sea urchin sperm and embryos can be considered the pioneers in marine invertebrate cryopreservation. It was from the 90s ...onwards when the number of references began to increase and diversify not only the range of species of interest but also in the cell types and fields of application. This work is an attempt to summarize the research published on marine invertebrates in a wide variety of journals regarding the development and the applications of marine invertebrate cryopreservation protocols. This paper reviews factors and trends, the obtained results, remaining technical constraints and the immediate future of marine invertebrate cryopreservation.
This study examinates the challenges of cryopreserving sea urchin (Paracentrotus lividus) eggs, a task hindered by factors like low membrane permeability and high sensitivity to cryoprotective agents ...(CPAs). While successful cryopreservation has been achieved for some marine invertebrates, eggs remain problematic due to their unique characteristics. The study explores the impact of various CPAs and cryopreservation techniques on sea urchin eggs, employing scanning and transmission electron microscopy to analyze cellular damage. The findings reveal that exposure to low CPA concentrations (0.5 M) did not induce significant damage to eggs. However, high concentrations (3 M) proved highly detrimental. Every cryopreservation approach investigated in this study resulted in irreversible damage to the sea urchin eggs, rendering them nonviable for future use. The research sheds light on the importance of understanding the structural alterations induced by CPAs and cryopreservation methods. This knowledge is essential for refining cryopreservation methods, potentially paving the way for successful preservation of these challenging cells.
Abstract
Shellfish aquaculture needs the development of new tools for the improvement of good practices avoiding the reliance on natural spat collection to increase production efficiently. The aim of ...this work was to improve the cryopreservation protocol for
Mytilus galloprovincialis
larvae described in Paredes et al. (in: Wolkers, Oldenhof (eds) Cryopreservation and freeze-drying protocol, methods in molecular biology, Humana Press, 2021, pp 2180,
https://doi.org/10.1007/978-1-0716-0783-1_18
). Moreover, the capability of producing adult mussels from cryopreserved 72 h-old D-larvae and potential long-term effects of cryopreservation through progenies were evaluated. The selection of 72-h old D-larvae for cryopreservation yielded 75% of recovery, higher than 50% from trochophores. The best combination was 10% Ethylene–Glycol + 0.4 M Trehalose in Filtered Sea Water (FSW) with cooling at − 1 °C/min and a water bath at 35 °C for thawing. Sucrose (SUC) solutions did not improve larval recovery (p > 0.05). At settlement, 5.26% of cryopreserved F1 larvae survived and over 70% settled. F2 cryopreservation produced 0.15% survival of spat and settlement varied from 35 to 50%. The delay of shell size showed on cryopreserved larvae declined throughout larval rearing without significant differences with controls from settlement point (p > 0.05). Long-term experiments showed that it is possible to obtain adult mussels from cryopreserved larvae and this tool does not compromise the quality of following progenies, neither for cryopreservation nor post-thawing development of them.
•We assessed the risk by input of UV filters into marine recreational waters.•UV filter concentrations measured in beach water ranged between 35 and 164ngL−1.•4-MBC and BP-3 toxicity thresholds to ...marine organisms were 4–5μgL−1.•EHMC and BP-4 were less toxic.•There is a potential risk to coastal environment for UV filters BP-3 and 4-MBC.
Due to the concern about the negative effects of exposure to sunlight, combinations of UV filters like 4-Methylbenzylidene-camphor (4-MBC), Benzophenone-3 (BP-3), Benzophenone-4 (BP-4) and 2-Ethylhexyl-4-methoxycinnamate (EHMC) are being introduced in all kind of cosmetic formulas. These chemicals are acquiring a concerning status due to their increasingly common use and the potential risk for the environment. The aim of this study is to assess the behaviour of these compounds in seawater, the toxicity to marine organisms from three trophic levels including autotrophs (Isochrysis galbana), herbivores (Mytilus galloprovincialis and Paracentrotus lividus) and carnivores (Siriella armata), and set a preliminary assessment of potential ecological risk of UV filters in coastal ecosystems. In general, EC50 results show that both EHMC and 4-MBC are the most toxic for our test species, followed by BP-3 and finally BP-4. The most affected species by the presence of these UV filters are the microalgae I. galbana, which showed toxicity thresholds in the range of μgL−1 units, followed by S. armata>P. Lividus>M. galloprovincialis. The UV filter concentrations measured in the sampled beach water were in the range of tens or even hundreds of ngL−1. The resulting risk quotients showed appreciable environmental risk in coastal environments for BP-3 and 4-MBC.
Cryopreservation is the only reliable method for long-term storage of biological material that guarantees genetic stability. This technique can be extremely useful for the conservation of endangered ...species and restock natural populations for declining species. Many factors have negatively affected the populations of high economical value shellfish in Spain and, as a result, many are declining or threatened nowadays. This study was focused on early-life stages of Venerupis corrugata, Ruditapes decussatus and Ruditapes philippinarum to develop successful protocols to enhance the conservation effort and sustainable shellfishery resources. Firstly, common cryoprotecting agents (CPAs) were tested to select the suitable permeable CPA attending to toxicity. Cryopreservation success using different combinations of CPA solutions, increasing equilibrium times and larval stages was evaluated attending to survival and shell growth at 2 days post-thawing. Older clam development stages were more tolerant to CPA toxicity, being ethylene-glycol (EG) and Propylene-glycol (PG) the least toxic CPAs. CPA solution containing EG yielded the highest post-thawing survival rate and the increase of equilibration time was not beneficial for clam larvae. Cryopreservation of trochophores yielded around 50% survivorship, whereas over 80% of cryopreserved D-larvae were able to recover after thawing.
La pandemia por enfermedad por coronavirus 2019 (COVID-19) aumentó la mortalidad mundial, más en poblaciones vulnerables como pacientes bajo terapia de remplazo renal (TRR). Se propuso evaluar la ...mortalidad de pacientes en TRR y si hubo diferencias entre las personas con o sin diabetes (DM). Métodos: Estudio retrospectivo, observacional de pacientes en TRR con SARS-CoV-2 por prueba de la reacción en cadena de la polimerasa transcriptasa reversa (RT-PCR) ingresados con distrés respiratorio para asistencia respiratoria al Hospital IESS Quito Sur (Ecuador, abril-diciembre 2020). Resultados: población de 93 pacientes bajo TRR con COVID-19 y dificultad respiratoria; media de edad de 65.6 años; hombres el 80.6%. La mortalidad fue del 36%, 38% con DM y 34.9% sin DM (χ2: 0.098; p = 0.75). Se observó que con mayor compromiso tomográfico pulmonar (3.1%; intervalo de confianza del 95% IC95%: –23.2 a 17.0%) aumentó la mortalidad (χ2: 3.409; p = 0.492), pero el único factor de riesgo de muerte fue la edad mayor a 60 años (odds ratio OR: 6.92; IC95%: 1.212-39.505). Conclusiones: Los pacientes internados en un Hospital de Quito bajo TRR tuvieron más dificultad respiratoria y mayor mortalidad por COVID-19 que la población general (más elevada que lo informado en el resto del mundo). No hubo diferencia de mortalidad entre pacientes con o sin diabetes (otras etiologías de enfermedad renal). La edad constituyó el mayor factor de riesgo de muerte por COVID-19 en pacientes bajo TRR.
In the present work we modulated two stress factors salinity and temperature, whose ranges have been previously determined by bioassays using six pre-treatments (18 °C-29.5‰; 18 °C-35‰; 18 °C-39‰ and ...20 °C-29.5‰; 20 °C-35‰; 20 °C-39‰), in order to obtain a successful cryopreservation protocol for pluteus larvae of the sea urchin P. lividus (Lamarck 1816). Toxicity tests were performed with different cryoprotectants in a range of 0.5–3 M. Best results pointed out to METH and Me2SO as those more suitable for cryopreservation. First an exploratory cryopreservation experiment with Me2SO supplemented with 0.04 M trehalose (TRE) was tested following the protocol for cryopreservation of embryos (8-h blastula) of Bellas and Paredes, 2011, which did not give satisfactory results. A cryopreservation experiment was performed with both cryoprotectants supplemented with 0.04 M trehalose on 4-arm pluteus larvae (48 h-old) developed in these pre-treatment conditions, followed by a simpler and shorter protocol with a cooling rate of 1 °C/min to −35 °C, achieving for the first time the successful cryopreservation of P. lividus larvae. When larvae were incubated in low salinity or low temperature pre-treatments, they showed delayed larval development and abnormalities. In contrast, pretreatments with high temperature and salinity showed good results. Dimethyl sulfoxide with trehalose proved to be the only effective cryoprotectant for successful cryopreservation of P. lividus larvae. The success of dimethyl sulfoxide is consistent with that described for other cases in previous literature, where dimethyl sulfoxide, although not the least toxic compound, gave the best cryopreservation result.
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