12 research outputs found
Male triploid oysters of Crassostrea gigas exhibit defects in mitosis and meiosis during early spermatogenesis
International audienceThe Pacific oyster, Crassostrea gigas is a successive irregular hermaphrodite mollusc which has an annual breeding cycle. Oysters are naturally diploid organisms, but triploid oysters have been developed for use in shellfish aquaculture, with the aim of obtaining sterile animals with commercial value. However, studies have shown that some triploid oysters are partially able to undergo gametogenesis, with numerous proliferating cells closed to diploids (3n alpha) or a partial one with an accumulation of locked germ cells (3n beta). The aim of our study therefore was to understand the regulation of spermatogenesis in both groups of triploid oysters (alpha and beta) from the beginning of spermatogenesis, during mitosis and meiosis events. Our results demonstrate that the reduced spermatogenesis in triploids results from a deregulation of the development of the germinal lineage and the establishment of the gonadal tract led by a lower number of tubules. Morphological cellular investigation also revealed an abnormal condensation of germ cell nuclei and the presence of clear patches in the nucleoplasm of triploid cells, which were more pronounced in beta oysters. Furthermore, studies of molecular and cellular regulation showed a downregulation of mitotic spindle checkpoint in beta oysters, resulting in disturbance of chromosomal segregation, notably on Spindle Assembly Checkpoint involved in the binding of microtubules to chromosomes. Taken together, our results suggest that the lower reproductive ability of triploid oysters may be due to cellular and molecular events such as impairment of spermatogenesis and disruptions of mitosis and meiosis, occurring early and at various stages of the gametogenetic cycle
Sample collection protocol for maturity staging of marine fish through histology
This protocol was set up under the MATO project (MATurité Objective des poissons par histologie quantitative), as part of Carine Sauger’s PhD. The MATO project, financed by IFREMER (Institut Français de Recherche pour l'Exploitation de la Mer), aims at improving the evaluation of sexual maturity stages of exploited stock species using histology paired with a stereology reading process. The present document gathers protocols used in the study of marine female fish gonads as well as the study of the different cellular structures found in ovaries at the Port-en-Bessin IFREMER laboratory. Materials used here are not always the most optimal but favor a manual approach. Most of the histological methods found in this protocol are based on methods described by Gabe, or were modified so as to answer our queries from a fisheries point of view, from the collection of fresh samples to the staining and mounting of histological slides, including inclusion in paraffin.Ce recueil de protocoles a été mis en place dans le cadre du projet MATO (MATurité Objective des poisons par histologie quantitative) et dans le cadre de la thèse de Carine Sauger. Le projet MATO financé par l’IFREMER (Institut Français de Recherche pour l’Exploitation de la Mer) a pour but d’améliorer la détermination de la maturité sexuelle chez certaines espèces en utilisant l’histologie couplé à la stéréologie. Ce présent document recueille les protocoles utilisés à la station IFREMER de Port-en-bessin pour l’étude de gonades femelles de poissons marins et des différentes structures cellulaires retrouvées dans les ovaires. Les protocoles présents détaillent les méthodes utilisées, de la récolte de l’échantillon frais jusqu’au montage de la lame histologique et sa coloration, en passant par l’inclusion dans la paraffine. Il a été mis en place de façon à favoriser une approche manuelle des méthodes d’histologie
Differential regulation of zinc efflux transporters ZnT-1, ZnT-5 and ZnT-7 gene expression by zinc levels: a real-time RT–PCR study
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Biosurveillance des masses d'eau en Normandie (France) en utilisant la moule saumâtre, Mytilopsis leucophaeata
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Macroscopic, histological and stereological image dataset of Megrim (Lepidorhombus whiffiagonis) ovaries from the ICES Celtic Seas, south of Greater North sea or Bay of Biscay Ecoregions
<p><strong>Contents: </strong></p><p>This dataset contains the macroscopic and histological images of the ovaries of 202 Megrim (female, <i>Lepidorhombus whiffiagonis</i>, Walbaum, 1792) collected from the ICES Celtic Seas, south Greater North sea or Bay of Biscay Ecoregions (Eco) in November 2019 (n=25; Eco=7h & 7j), November 2020 (n=14, Eco=7h & 7j), December 2020 (n=1, Eco=7h), May 2021 (n=15, Eco=7h & 7g), June 2021 (n=15, Eco=7h), July 2021 (n=15, Eco=7h & 7e), October 2021 (n=15, Eco=7g & 7f), October 2021 (n=6, Eco=8a & 8b & 8c), November 2021 (n=6, Eco=8a & 8b), November 2021 (n=15, Eco=7j), December 2021 (n=15, Eco=7e & 7g), January 2022 (n=15, Eco=7f), February 2022 (n=15, Eco=7g), March 2022 (n=15, Eco=7g) and May 2022 (n=15, Eco=7g).</p><p> </p><p><strong>Images:</strong></p><ul><li><strong>Macroscopic_pictures.zip: </strong>archive in zip format of 549 pictures (.JPG; 2Mo-8Mo; JPG; 350pp) from 202 female megrim dissected during this study. Each photo was taken with a digital camera (no flash). For each individual, up to three pictures were taken when possible (Le Meleder <i>et al.</i>, 2022) with : <ul><li>one picture of the entire fish with its abdominal cavity open with the ovaries in view</li><li>one picture of the whole fish with the ovaries outside of the abdominal cavity</li><li>one picture of the ovaries</li><li>the name of the picture is the same as the fish's ID number.</li></ul></li><li><strong>Histology_slides.zip :</strong> archive in zip format containing the ovarian histological slides digitized using an Aperio CS (Scan Scope Console software, v.10.2.0.2352), x20 lens. The whole slide images (.svs) are of the 461 histological slides acquired during this study. </li></ul><p> </p><p><strong>Data:</strong></p><ul><li><strong>Readings.zip :</strong> archive in zip format containing the stereology reading results of the ovarian histological slides. In this folder, three directories are available. <ul><li><strong>Calibration</strong> : Reading results of 3 different agents, with the first and last readings, as well as the QuPath scripts used.</li><li><strong>Homogeneity</strong> : Reading results for 102 histological slides used to check the cellular homogeneity inter- and intra-gonad. These 102 slides belong to 17 fish, with three histological samples taken in the anterior (1), median (2) and posterior (3) sections of the left (G) and right (D) ovaries. A QuPath folder is also present, containing the scripts used.</li><li><strong>Total </strong>: Reading results for 202 ovarian histological slides of the median position of either the left or right ovary. One median slide was read per sampled fish. A QuPath folder is also present, containing the scripts used.</li></ul></li><li><strong>Macro_WHI_read_me.txt</strong> : a text file (.txt) listing the acronyms used in the <strong>Macro_WHI.xlsx</strong> file, as well as their meaning.</li><li><strong>Macro_WHI.xlsx</strong> : Excel file (.xlsx) containing measurements of macroscopic parameters for all 202 fish sampled during this study. The information contained in this table is as follows: <ul><li>Fish_id: identification of the fish. This id is identical to the name given to the pictures of the full ovaries (<strong>Macroscopic_pictures_Data</strong>)</li><li>ICES _Division: International Council for the Exploration of the Sea (ICES) division where the fish was sampled in the Food and agricultural Organization of the United nations (FAO) fishing area 27</li><li>ICES_statistical_rectangle : Statistical rectangle where the fish was sampled within the FAO fishing area 27</li><li>Date: date the fish was caught (dd/mm/yyyy)</li><li>Total_fish_length: total length of the fish (cm)</li><li>Ungutted_fish_weight: total weight of the fish (g)</li><li>Otolith_ID: unique identification number given to each sampled fish through the Imagine (Ellebode <i>et al.</i>, 2022) software used by IFREMER</li><li>Parasite: presence (Y) or absence (N) of parasite in or on the fish</li><li>age: age (in years) of the fish after analysis of the fish's otolith. The IFREMER laboratory of Boulogne-sur-Mer (FRANCE) executed this analysis</li><li>Visual_maturity : visually estimated maturity, after observation macroscopic criteria of the fish's gonad with the naked eye, following the WKASMSF (ICES, 2018) scale</li><li>Liver_weight: liver weight (g)</li><li>Droite_gonad_weight : gonad weight (g) of right ovary</li><li>Gauche_gonad_weight : gonad weight (g) of left ovary</li><li>Sections: number of cross sections sampled for the individual</li></ul></li><li><strong>Stereo_MULL_read_me.txt</strong> : a text file (.txt) listing the acronyms used in the <strong>Stereo_MULL.csv</strong> file, as well as their meaning.</li><li><strong>Stereo_MULL.csv</strong> : a text data file (.csv) of the stereology count results of 287 slides read during this study. Among these slides, 102 were read to test the homogeneity distribution of different cell types found throughout each ovary (17 fish with 6 histological sections : a median, an anterior and a posterior histological section, for both ovaries), slides were read by multiple agents for calibration purposes (see <strong>Calibration</strong> folder for reading results of the 3 agents). Finally, 202 median histological ovarian slides were read. The information contained in this table is as follows: <ul><li>cell_type: structure identified for one sample point (for the abbreviations, see Heude-Berthelin <i>et al.</i> 2023)</li><li>idpt: identification number of the sampling point</li><li>id: unique complex identification number of the sampling point generated by combining the x and y coordinates</li><li>x: x coordinate of the sampling point</li><li>y: y coordinate of the sampling point</li><li>reading: Indicates if the reading data was used to test cellular homogeneity (Homogeneity) or to the sexual maturity phase</li><li>slideid: identification number of the digitized histological slide that was used for the stereological count. Shares the same 12 first characters with <strong>Fish_id</strong></li></ul></li></ul><p> </p><p><strong>Contact :</strong></p><p>This dataset was established under the MATO (MATurité Objectif des poissons par l'histologie quantitative) project, during the PhD of Carine Sauger (October 2021-2023), financed by France Fillière Pêche (FFP/2020/AM/MF/109), under the supervision of IFREMER (Institut Français de Recherche pour l'Exploitation de la Mer) and BOREA (Biologie des Organismes et Ecosystèmes Aquatiques), and with the collaboration of a research facility from the University of Caen-Normandie : CMABIO3 (Centre de Microscopie Appliquée à la Biologie). For any enquiries, please contact: [email protected] or [email protected]</p>
Stereology reading protocol when using quantitative histology for the determination of sexual maturity in fish ovaries
This protocol was established for the evaluation of sexual maturity for exploited stock species, using quantitative histology (stereology). This document describes the reading method used on histological slides under the cross-platform QuPath. This document follows the work of different workshops that aimed to improve the compilation of data on sexual maturity. The WKMATCH (WorKshop for MATurity staging CHairs, 2012) and the WKASMSF (Workshop for Advancing Sexual Maturity Staging in Fish, 2018) defined a universal evaluation grid for sexual maturity staging of different species, including teleosteans. During the WKMATCH workshop, two main recommendations were made, underlining the need to improve and complete knowledge on sexual maturity, as well as to harmonize the practices used to determine these sexual phases. Another workshop, the WKMATHIS (WorKshop on sexual MATurity staging from HIStological tools) that took place in Caen in 2017, added new objectives : review the current knowledge on gonad histology, determine a sexual maturity scale at a cellular level, and histological studies should be made in order to improve the determination of sexual maturity on a macroscopic scale. This protocol, drawn from these workshops and their conclusions, offers guidelines on how to read histological slides through the use of stereology. As of June 2022, this protocol is linked to the MATO (MATurité Objectif des poissons par l’histologie quantitative) project, a study restricted to female gonad and the different cellular structures found inside the ovaries for different species (Pleuronectes platessa, Lepidorhombus whiffiagonis, Lepidorhombus boscii, Mullus surmuletus and Micromesistius poutassou). This protocol will present reading methods that favor an objective reading of histological slides, through stereology, and will allow less experienced readers to partake in this exercise. For a detailed description of the germinal cells, refer to the lexicon of the studied speci
Protective effect of intravitreal injection of vasoactive intestinal peptide-loaded liposomes on experimental autoimmune uveoretinitis.
International audienceInsulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein 3 (IGFBP-3) are involved in oxidative stress and atherosclerosis; however, the relationship between the IGF-I system and atrial fibrillation (AF) is not known. The objective of this analysis was to assess, the relationship between IGF-I and IGFBP-3 serum levels and AF among elderly participants