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Dentin-Pulp Complex Regeneration
Published in Vincenzo Guarino, Marco Antonio Alvarez-Pérez, Current Advances in Oral and Craniofacial Tissue Engineering, 2020
Amaury Pozos-Guillén, Héctor Flores
All tissues originate from stem cells, which play an indispensable role in embryonic development and tissue regeneration. These cells are capable of self-renewal, proliferation, and differentiation into multiple mature cell types. Stem cell potency describes the potential of the cell to divide and express different cell phenotypes. Totipotent stem cells are able to divide and produce all the cells in an individual. Pluripotent stem cells have not completely divided and can become many cells, but not all lineages. They are able to differentiate into any of the three germ layers: endoderm, mesoderm or ectoderm, where the progeny has multiple distinct phenotypes, whilst multipotent stem cells can differentiate into cells from multiple, but a limited number of lineages (Robey 2000).
Using mathematical modelling to investigate the effect of the sexual behaviour of asymptomatic individuals and vector control measures on Zika
Published in Letters in Biomathematics, 2019
S. Bañuelos, M. V. Martinez, C. Mitchell, A. Prieto-Langarica
There are two ways Wolbachia can be beneficial in reducing the spread of Zika. The first is that it can be used to reduce the mosquito population as well as mosquito life span (Schraiber et al., 2012; Walker et al., 2011). When a male mosquito is infected with a strain of Wolbachia its sperm becomes modified such that embryos die during early embryonic development. This method is very much dependent on the prevalence of Wolbachia in the mosquito population, since uninfected female mosquitoes are less likely to mate with Wolbachia-infected males. Thus there is a risk of the strain becoming obsolete (Jiggins, 2017). The second way Wolbachia can help in stopping the spread of Zika is that it has been shown to greatly reduce the capacity of Zika-infected mosquitoes to harbour and transmit the disease (Hughes & Britton, 2013; Ndii, Hickson, & Mercer, 2012).
Glyphosate disrupts sperm quality and induced DNA damage of rainbow trout (Oncorhynchus mykiss) sperm
Published in Journal of Environmental Science and Health, Part C, 2021
Ayşe Akça, Mehmet Kocabaş, Filiz Kutluyer
In summary, the detailed analyses provided by this study indicated the deleterious effect of GLY on rainbow trout spermatozoa after exposure, especially in the percentage and duration of motility, even in lower concentrations. Furthermore, higher concentrations of GLY induced loss of DNA integrity. The adverse effects of GLY exposure on rainbow trout spermatozoa were revealed by abnormal sperm quality parameters and in DNA damage detected by comet assays. These tools could be used in other monitoring the male reproductive toxicity of pollutants in fish. Future studies could focus on fertility and embryonic development in offspring after GLY exposure to sperm cells.
Acute toxicity of three herbicide formulations of Astyanax altiparanae (Characiformes, Characidae), an emerging neotropical fish model species
Published in Journal of Toxicology and Environmental Health, Part A, 2023
Nathalia R. A. Rocha, Thiago A. Freato, José T. Filho, Admilson C. Barbosa, Talita M. Lázaro, Gabriel M. Schade, Gabriella B. Carvalho, Carlos A. F. Oliveira, José A. Senhorini, George S. Yasui, Paulo S. Monzani
Folmar, Sanders, and Julin (1979) reported that Roundup LC50 values for fish vary according to the stage of development and that larvae and juveniles are more sensitive to herbicides than adults. The LC50 for A. altiparanae embryos during the initial embryonic development, from zygote to hatching, was assessed with an interval of approximately 17 hr. Rapid embryonic development makes it impossible to examine the 96 hr LC50 for a specific stage. The 96 hr LC50 for Roundup in the eyed egg stage and large fish Oncorhynchus mykiss were 16 and 8.3 mg/L glyphosate, respectively (Folmar, Sanders, and Julin 1979). These results are in agreement with our findings, where adult A. altiparanae were more sensitive to herbicides than to initial embryonic development. However, further developmental stages, such as sac fry (LC50 3.4 mg/L), swim-up fry (LC50 2.4 mg/L), and fingerling at 1 g (LC50 1.3 mg/L), were more susceptible to Roundup formulation than larger O. mykiss (Folmar, Sanders, and Julin 1979). Similar results were observed for Ictalurus punctatus, in which the sac fry and swim-up fry exhibited 96 hr LC50 values of 4.3 and 3.3 mg/L glyphosate, respectively, while large fish displayed an LC50 of 13 mg/L glyphosate (Folmar, Sanders, and Julin 1979). Data suggested that the eyed egg stage is the least sensitive to glyphosate. In this study, the 96 hr LC50 values observed in adult A. altiparanae for Roundup Transorb® (3.14 mg/L glyphosate ae) showed an intermediate LC50 value related to Pimephales promelas (2.3 mg/L) and Lepomis macrochirus (5 mg/L) using the Roundup formulation (Folmar, Sanders, and Julin 1979). However, the composition difference between Roundup used by Folmar, Sanders, and Julin (1979) and Roundup Transorb used in this study is found in the concentration of glyphosate salt and acid equivalent, as well as the other ingredients (surfactants) not specified by manufacturers. These differences in the herbicide formulations might account for differing LC50s for each product.