25 results on '"Cerdà, Joan"'
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2. Spermatogenesis: The development from stem cells to sperm and its regulation by hormones and growth factors
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Schulz, Rüdiger W., primary, Crespo, Diego, additional, Chauvigné, François, additional, and Cerdà, Joan, additional
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- 2023
- Full Text
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3. Oogenesis, Fish Amphibians
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Cerdà, Joan, primary
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- 2018
- Full Text
- View/download PDF
4. Towards cross-lingual voice cloning in higher education
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Universitat Politècnica de València. Departamento de Sistemas Informáticos y Computación - Departament de Sistemes Informàtics i Computació, AGENCIA ESTATAL DE INVESTIGACION, European Regional Development Fund, COMISION DE LAS COMUNIDADES EUROPEA, Universitat Politècnica de València, Pérez-González de Martos, Alejandro Manuel, Garcés Díaz-Munío, Gonçal, Giménez Pastor, Adrián, Silvestre Cerdà, Joan Albert, Sanchis Navarro, José Alberto, Civera Saiz, Jorge, Jiménez, Manuel, Turró Ribalta, Carlos, Juan, Alfons, Universitat Politècnica de València. Departamento de Sistemas Informáticos y Computación - Departament de Sistemes Informàtics i Computació, AGENCIA ESTATAL DE INVESTIGACION, European Regional Development Fund, COMISION DE LAS COMUNIDADES EUROPEA, Universitat Politècnica de València, Pérez-González de Martos, Alejandro Manuel, Garcés Díaz-Munío, Gonçal, Giménez Pastor, Adrián, Silvestre Cerdà, Joan Albert, Sanchis Navarro, José Alberto, Civera Saiz, Jorge, Jiménez, Manuel, Turró Ribalta, Carlos, and Juan, Alfons
- Abstract
[EN] The rapid progress of modern AI tools for automatic speech recognition and machine translation is leading to a progressive cost reduction to produce publishable subtitles for educational videos in multiple languages. Similarly, text-to-speech technology is experiencing large improvements in terms of quality, flexibility and capabilities. In particular, state-of-the-art systems are now capable of seamlessly dealing with multiple languages and speakers in an integrated manner, thus enabling lecturer¿s voice cloning in languages she/he might not even speak. This work is to report the experience gained on using such systems at the Universitat Politècnica de València (UPV), mainly as a guidance for other educational organizations willing to conduct similar studies. It builds on previous work on the UPV¿s main repository of educational videos, MediaUPV, to produce multilingual subtitles at scale and low cost. Here, a detailed account is given on how this work has been extended to also allow for massive machine dubbing of MediaUPV. This includes collecting 59 h of clean speech data from UPV¿s academic staff, and extending our production pipeline of subtitles with a state-of-the-art multilingual and multi-speaker text-to-speech system trained from the collected data. Our main result comes from an extensive, subjective evaluation of this system by lecturers contributing to data collection. In brief, it is shown that text-to-speech technology is not only mature enough for its application to MediaUPV, but also needed as soon as possible by students to improve its accessibility and bridge language barriers.
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- 2021
5. Streaming cascade-based speech translation leveraged by a direct segmentation model
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Universitat Politècnica de València. Departamento de Sistemas Informáticos y Computación - Departament de Sistemes Informàtics i Computació, GENERALITAT VALENCIANA, MINISTERIO DE EDUCACION, AGENCIA ESTATAL DE INVESTIGACION, European Regional Development Fund, COMISION DE LAS COMUNIDADES EUROPEA, MINISTERIO DE CIENCIA INNOVACION Y UNIVERSIDADES, Iranzo-Sánchez, Javier, Jorge-Cano, Javier, Baquero-Arnal, Pau, Silvestre Cerdà, Joan Albert, Giménez Pastor, Adrián, Civera Saiz, Jorge, Sanchis Navarro, José Alberto, Juan, Alfons, Universitat Politècnica de València. Departamento de Sistemas Informáticos y Computación - Departament de Sistemes Informàtics i Computació, GENERALITAT VALENCIANA, MINISTERIO DE EDUCACION, AGENCIA ESTATAL DE INVESTIGACION, European Regional Development Fund, COMISION DE LAS COMUNIDADES EUROPEA, MINISTERIO DE CIENCIA INNOVACION Y UNIVERSIDADES, Iranzo-Sánchez, Javier, Jorge-Cano, Javier, Baquero-Arnal, Pau, Silvestre Cerdà, Joan Albert, Giménez Pastor, Adrián, Civera Saiz, Jorge, Sanchis Navarro, José Alberto, and Juan, Alfons
- Abstract
[EN] The cascade approach to Speech Translation (ST) is based on a pipeline that concatenates an Automatic Speech Recognition (ASR) system followed by a Machine Translation (MT) system. Nowadays, state-of-the-art ST systems are populated with deep neural networks that are conceived to work in an offline setup in which the audio input to be translated is fully available in advance. However, a streaming setup defines a completely different picture, in which an unbounded audio input gradually becomes available and at the same time the translation needs to be generated under real-time constraints. In this work, we present a state-of-the-art streaming ST system in which neural-based models integrated in the ASR and MT components are carefully adapted in terms of their training and decoding procedures in order to run under a streaming setup. In addition, a direct segmentation model that adapts the continuous ASR output to the capacity of simultaneous MT systems trained at the sentence level is introduced to guarantee low latency while preserving the translation quality of the complete ST system. The resulting ST system is thoroughly evaluated on the real-life streaming Europarl-ST benchmark to gauge the trade-off between quality and latency for each component individually as well as for the complete ST system.
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- 2021
6. La perspectiva de personas migrantes sobre el acceso a la atención sanitaria en el contexto de políticas de austeridad en Andalucía
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Universidad de Sevilla. Departamento de Enfermería, Ruiz-Azarola, Ainhoa, Escudero Carretero, María, López-Fernández, Luis Andrés, Gil García, Eugenia, March Cerdà, Joan Carles, López Jaramillo, Daniel, Universidad de Sevilla. Departamento de Enfermería, Ruiz-Azarola, Ainhoa, Escudero Carretero, María, López-Fernández, Luis Andrés, Gil García, Eugenia, March Cerdà, Joan Carles, and López Jaramillo, Daniel
- Abstract
Objetivo Conocer la valoración de personas migrantes sobre su acceso al sistema sanitario tras la entrada en vigor del Real Decreto-Ley16/2012 y sobre el efecto que han podido producir los recortes económicos en dicho acceso. Método Estudio cualitativo fenomenológico con entrevistas semiestructuradas, realizado en Andalucía, en dos fases (2009-2010 y 2012-2013), con 36 participantes. Se segmentó la muestra por tiempo de estancia, nacionalidad y ámbito de residencia. Las nacionalidades de las personas migrantes son Bolivia, Marruecos y Rumanía. Resultados Como elementos facilitadores del acceso en ambas fases se identifican la situación administrativa regular, la posesión de tarjeta sanitaria individual, el conocimiento del idioma, las redes sociales y la información. Los resultados muestran diferencias en el acceso a la atención sanitaria de las personas migrantes antes y después de la aplicación del RDL 16/2012, en el marco de las políticas de austeridad. En la segunda fase se agravan algunas barreras de acceso, como los tiempos de espera y la incompatibilidad de horarios, y empeoran las condiciones socioeconómicas y administrativas de las personas participantes. Conclusiones El diseño de políticas económicas y de regulación de la atención sanitaria debería tener en cuenta las barreras y los facilitadores de acceso como ejes fundamentales de la protección de la salud de las personas migrantes y, por ende, de la población general., Objective To conduct an assessment of migrant people regarding their access to the health system following entry into force of Royal Decree-Law 16/2012 along with the impact of economic cuts on such access. Method Qualitative phenomenological study with semi-structured interviews, conducted in Andalusia (Spain), in two phases (2009-2010 and 2012-2013), with 36 participants. The sample was segmented by length of stay, nationality and area of residence. The nationalities of origin are Bolivia, Morocco and Romania. Results Elements facilitating access in both periods: regular administrative situation, possession of Individual Health Card, knowledge of the language, social networks and information. The results show differences in access to health care for migrants before and after the enforcement of the RDL 16/2012, within austerity policies. In the second period, access barriers such as waiting times or incompatibility of schedules are aggravated and the socio-economic and administrative conditions of participants worsen. Conclusions The design of policies, economic and regulatory health care, should take into account barriers and facilitators of access as fundamental main points of health protection for migrants and, therefore, for the general population.
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- 2020
7. Complex between cationic like-charged polyelectrolytes/surfactants systems
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Ministerio de Economía y Competitividad (España), European Commission, Bassalah, Mohamed E. A., Cerdà, Joan J., Sintes, Tomàs, Aschi, Adel, Othman, Tahar, Ministerio de Economía y Competitividad (España), European Commission, Bassalah, Mohamed E. A., Cerdà, Joan J., Sintes, Tomàs, Aschi, Adel, and Othman, Tahar
- Abstract
We report for the first time the complex formation between cationic like-charged polyelectrolytes and surfactant systems. The mechanism of attraction has been investigated through extensive course-grained molecular dynamic simulations and atomic force microscopy (AFM) experiments. The addition of a tetravalent salt is found to play a crucial role in the polyelectrolyte backbone properties. We found extended structures at low and high salt concentration values, whereas, for intermediate ones, the chains condensate. The combination of elements with the same charge has been investigated in three different regimes depending on the tetrasalt concentration: before condensation; at the condensation point and during the re-expansion. The mixture of polyelectrolytes and surfactants in salt free is also studied and compared to the mixture in a tetrasalt solution.
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- 2017
8. Efficiency and usability study of innovative computer-aided transcription strategies for video lecture repositories
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Universitat Politècnica de València. Departamento de Sistemas Informáticos y Computación - Departament de Sistemes Informàtics i Computació, European Commission, Ministerio de Economía y Competitividad, Valor Miró, Juan Daniel, Silvestre Cerdà, Joan Albert, Civera Saiz, Jorge, Turró Ribalta, Carlos, Juan Císcar, Alfonso, Universitat Politècnica de València. Departamento de Sistemas Informáticos y Computación - Departament de Sistemes Informàtics i Computació, European Commission, Ministerio de Economía y Competitividad, Valor Miró, Juan Daniel, Silvestre Cerdà, Joan Albert, Civera Saiz, Jorge, Turró Ribalta, Carlos, and Juan Císcar, Alfonso
- Abstract
[EN] Video lectures are widely used in education to support and complement face-to-face lectures. However, the utility of these audiovisual assets could be further improved by adding subtitles that can be exploited to incorporate added-value functionalities such as searchability, accessibility, translatability, note-taking, and discovery of content-related videos, among others. Today, automatic subtitles are prone to error, and need to be reviewed and post-edited in order to ensure that what students see on-screen are of an acceptable quality. This work investigates different user interface design strategies for this post-editing task to discover the best way to incorporate automatic transcription technologies into large educational video repositories. Our three-phase study involved lecturers from the Universitat Polite`cnica de Vale`ncia (UPV) with videos available on the poliMedia video lecture repository, which is currently over 10,000 video objects. Simply by conventional post-editing automatic transcriptions users almost reduced to half the time that would require to generate the transcription from scratch. As expected, this study revealed that the time spent by lecturers reviewing automatic transcriptions correlated directly with the accuracy of said transcriptions. However, it is also shown that the average time required to perform each individual editing operation could be precisely derived and could be applied in the definition of a user model. In addition, the second phase of this study presents a transcription review strategy based on confidence measures (CM) and compares it to the conventional post-editing strategy. Finally, a third strategy resulting from the combination of that based on CM with massive adaptation techniques for automatic speech recognition (ASR), achieved to improve the transcription review efficiency in comparison with the two aforementioned strategies. 2015 Elsevier B.V. All rights reserved.
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- 2015
9. PLEUROGENE: flatfish genomics and proteomics for aquaculture
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Cerdà, Joan, Martínez-Rodríguez, Gonzalo, Piferrer, Francesc, Prat, Francisco, and Yúfera, Manuel
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Proteomics ,Reproduction ,Larval development ,Flatfish ,Genomics - Abstract
Cerdà, Joan ... et al.-- Abstracts of the Annual Main Meeting of the Society for Experimental Biology, A2 Genomics in Aquaculture, 11-15 July 2005, Universitat Autonoma de Barcelona, Barcelona, Spain.-- 1 page, Senegal sole (Solea senegalensis) and Atlantic halibut (Hippoglossus hippoglossus) are two flatfish yielding high value market products with good potential for aquaculture in Mediterranean Europe and eastern North America, respectively. Productionrelated problems in these two phylogenetically related species may be addressed with improved knowledge of important basic biological processes such as reproduction, development, nutrition, genetics and immunity. The use of genomic and proteomic approaches to thoroughly characterize these processes will translate into knowledge that can be used to overcome the production obstacles and create (for Senegal sole) or expand (for Atlantic halibut) solid aquaculture industries. PLEUROGENE is a new research programme funded by Genome Spain and Genome Canada with two main goals: the analysis of global gene expression during sex differentiation, reproduction, larval development, immunity and nutrition, and the construction of genetic linkage maps for use in the selection of improved broodstock. High-throughput genome- and proteome-based technologies will be applied to establish gene expression profiling during these processes and to discover novel genes. All genetic, molecular and morphological information obtained in this project will be integrated into an interactive bioinformatics platform specifically developed, the Solea-mold. The knowledge generated by the PLEUROGENE project will ultimately lead to the establishment of new technologies for the control of reproduction and optimization of larval health and nutrition in the Senegal sole, Atlantic halibut, and other related flatfish species under intensive culture conditions
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- 2005
10. Dietary modulation of arachidonic acid metabolism in senegalese sole (Solea Senegalensis) broodstock reared in captivity
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Norambuena, Fernando, Morais, Sofia, Estévez, Alicia, Bell, J. Gordon, Tocher, Douglas R., Navarro, Juan Carlos, Cerdà, Joan, Duncan, Neil, Norambuena, Fernando, Morais, Sofia, Estévez, Alicia, Bell, J. Gordon, Tocher, Douglas R., Navarro, Juan Carlos, Cerdà, Joan, and Duncan, Neil
- Abstract
Previous studies have shown higher levels of arachidonic acid (20:4n-6, ARA) in testis, liver, and muscle of wild Senegalese sole (Solea senegalensis) compared to fish reared in captivity (first generation, G1). The present study was conducted to establish the optimal level of dietary ARA for G1 Senegalese sole broodstock, using as a reference the fatty acid profile of wild broodstock (gonads, liver and muscle). A total of 120 Senegalese sole broodstock were randomly distributed into 12 tanks (1:1 male and female) and fed in duplicate with six experimental diets containing increasing amounts of ARA (0.7%, 1.6%, 2.3%, 3.2%, 5.0%, and 6.0 % of total fatty acids) for 9. months. The relative ARA levels in liver, muscle and male and female gonads at the end of the feeding period increased in a dose dependent manner. Dietary ARA was mainly incorporated and stored in testis or ovary, followed by liver and muscle. Fish fed 2.3% and 3.2% ARA showed no differences in the ARA content of testis, ovary and liver when compared to wild fish. In male fish, a significant increase in the levels of 22:4n-6 and 22:5n-6 fatty acids was also observed, which was consistent with the up-regulation of fatty acyl elongase ( elovl5) and desaturase ( d4fad) transcript levels in the liver of fish fed 0.7%, 2.3% and 6% ARA. These results suggest that dietary inclusion of 3.2% ARA during periods shorter than 9. months, or of 2.3% ARA for prolonged periods, can maintain optimal levels of tissue ARA in captive Senegalese sole broodstock. In addition, the data indicate that male Senegalese sole is able to elongate and desaturate ARA to 22:4n-6 and 22:5n-6, suggesting that these fatty acids may be important for male reproduction. © 2012 Elsevier B.V.
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- 2013
11. Explicit length modelling for statistical machine translation
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Universitat Politècnica de València. Departamento de Sistemas Informáticos y Computación - Departament de Sistemes Informàtics i Computació, Universitat Politècnica de València. Departamento de Estadística e Investigación Operativa Aplicadas y Calidad - Departament d'Estadística i Investigació Operativa Aplicades i Qualitat, European Commission, Ministerio de Ciencia e Innovación, Ministerio de Industria, Turismo y Comercio, Generalitat Valenciana, Universitat Politècnica de València, Ministerio de Educación, Silvestre Cerdà, Joan Albert, Andrés Ferrer, Jesús, Civera Saiz, Jorge, Universitat Politècnica de València. Departamento de Sistemas Informáticos y Computación - Departament de Sistemes Informàtics i Computació, Universitat Politècnica de València. Departamento de Estadística e Investigación Operativa Aplicadas y Calidad - Departament d'Estadística i Investigació Operativa Aplicades i Qualitat, European Commission, Ministerio de Ciencia e Innovación, Ministerio de Industria, Turismo y Comercio, Generalitat Valenciana, Universitat Politècnica de València, Ministerio de Educación, Silvestre Cerdà, Joan Albert, Andrés Ferrer, Jesús, and Civera Saiz, Jorge
- Abstract
[EN] Explicit length modelling has been previously explored in statistical pattern recognition with successful results. In this paper, two length models along with two parameter estimation methods and two alternative parametrisations for statistical machine translation (SMT) are presented. More precisely, we incorporate explicit bilingual length modelling in a state-of-the-art log-linear SMT system as an additional feature function in order to prove the contribution of length information. Finally, a systematic evaluation on reference SMT tasks considering different language pairs proves the benefits of explicit length modelling.
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- 2012
12. Molecular and functional characterization of catfish (Heteropneustes fossilis) aquaporin-1b: Changes in expression during ovarian development and hormone-induced follicular maturation
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Chaube, Radha, Chauvigné, François, Tingaud-Sequeira, Angèle, Joy, Keerikkattil P., Acharjee, Arup, Singh, Varsha, Cerdà, Joan, Chaube, Radha, Chauvigné, François, Tingaud-Sequeira, Angèle, Joy, Keerikkattil P., Acharjee, Arup, Singh, Varsha, and Cerdà, Joan
- Abstract
The oocytes of the freshwater catfish Heteropneustes fossilis hydrate during hormone-induced meiotic maturation. To investigate if this process may be mediated by aquaporins (AQPs), as it occurs in marine fish producing highly hydrated eggs, the cloning of ovarian AQPs in catfish was carried out. Using degenerate primers for conserved domains of the major intrinsic protein (MIP) family, and 5′ and 3′end amplification procedures, a full-length cDNA encoding for an AQP1-like protein was isolated. The predicted protein showed the typical six transmembrane domains and two Asn-Pro-Ala (NPA) motifs conserved among the members of the AQP superfamily. Phylogenetic analysis indicated that the catfish AQP clustered with the teleost-specific aquaporin-1b subfamily, and accordingly it was termed HfAqp1b. Heterologous expression in Xenopus laevis oocytes indicated that HfAqp1b encoded for a functional AQP, water permeability being enhanced by cAMP. Site-directed mutagenesis revealed that cAMP induced the translocation of HfAqp1b into the oocyte plasma membrane most likely through the phosphorylation of HfAqp1b Ser227. In adult catfish, hfaqp1b transcripts were detected exclusively in ovary and brain and showed significant seasonal variations; in the ovary, hfaqp1b was maximally expressed during the pre-spawning period, whereas in the brain the highest expression was detected during spawning. In vitro stimulation of isolated catfish ovarian follicles with vasotocin (VT) or human chorionic gonadotropin (hCG), which induce oocyte maturation and hydration, elevated the hfaqp1b transcript levels after 6 or 16 h of incubation, respectively. These results suggest that HfAqp1b may play a role during VT- and hCG-induced oocyte hydration in catfish, and that VT may regulate HfAqp1b at the transcriptional and post-translational level in a manner similar to the vasopressin-dependent mammalian AQP2
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- 2011
13. Cathepsin B differential expression and enzyme processing and activity during Fundulus heteroclitus embryogenesis
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Tingaud-Sequeira, Angèle, Carnevali, Oliana, Cerdà, Joan, Tingaud-Sequeira, Angèle, Carnevali, Oliana, and Cerdà, Joan
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The role of lysosomal proteases such as cathepsin B (Ctsb) and one of the paralogs of cathepsin L (Ctsla) during yolk metabolism in fish oocytes is well established. However, the function of Ctsb during embryogenesis, particularly in marine teleosts, has been poorly documented. In this study, the spatio-temporal expression of Ctsb and Ctsla, their enzymatic activities, and the processing of the Ctsb and its cellular localization, was investigated in developing embryos of the killifish (Fundulus heteroclitus). Both fhctsb and fhctsla transcript levels, as well as cathepsin B- and L-like activities, gradually increased in embryos from the 2–4 cell stage up to 7 days post-fertilization. During the morula to gastrula transition an increase of the active FhCtsb single chain form was followed by a rise in cathepsin B activity, which were apparently regulated by post-transcriptional mechanisms. During neurulation, a 8-fold increase in cathepsin B activity was accompanied by a more moderate increase in cathepsin L activity, which was 6-fold enhanced by 7 dpf. These increased catalytic activities were well-correlated to changes in the electrophoretic pattern of yolk proteins and a strong expression of fhctsb and its protein product in the yolk syncytial layer. The increase of cathepsin B activity was further correlated with an increment of the relative amount of the FhCtsb single and double chain forms, both active forms of FhCtsb. These results suggest that FhCtsb may be involved in the mechanisms underlying the onset of gastrulation in F. heteroclitus embryos, and may play complementary roles with FhCtsla during yolk metabolism
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- 2011
14. Gilthead sea bream (Sparus auratus) and European sea bass (Dicentrarchus labrax) expressed sequence tags: Characterization, tissue-specific expression and gene markers
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Louro, Bruno, Passos, Ana Lúcia S., Souche, Erika L., Tsigenopoulos, Costas, Beck, Alfred, Lagnel, Jacques, Bonhomme, François, Cancela, Leonor, Cerdà, Joan, Clark, Melody S., Lubzens, Esther, Magoulas, Antonis, Planas, Josep V., Volckaert, Filip A.M., Reinhardt, Richard, Canario, Adelino V.M., Louro, Bruno, Passos, Ana Lúcia S., Souche, Erika L., Tsigenopoulos, Costas, Beck, Alfred, Lagnel, Jacques, Bonhomme, François, Cancela, Leonor, Cerdà, Joan, Clark, Melody S., Lubzens, Esther, Magoulas, Antonis, Planas, Josep V., Volckaert, Filip A.M., Reinhardt, Richard, and Canario, Adelino V.M.
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The gilthead sea bream. Sparus auratus, and the European sea bass, Dicentrarchus labrax, are two of the most important marine species cultivated in Southern Europe. This study aimed at increasing genomic resources for the two species and produced and annotated two sets of 30,000 expressed sequence tags (EST) each from 14 normalized tissue-specific cDNA libraries from sea bream and sea bass. Clustering and assembly of the ESTs formed 5268 contigs and 12,928 singletons for sea bream and 4573 contigs and 13,143 singletons for sea bass, representing 18,196 and 17,716 putative unigenes, respectively. Assuming a similar number of genes in sea bass, sea bream and in the model fish Gasterosteus aculeatus genomes, it was estimated that approximately two thirds of the sea bream and the sea bass transcriptomes were covered by the unigene collections. BLAST sequence similarity searches (using a cut off of e-value <10(-5)) against fully the curated SwissProt (and TrEMBL) databases produced matches of 28%(37%) and 43%(53%) of the sea bream and sea bass unigene datasets respectively, allowing some putative designation of function. A comparative approach is described using human Ensembl peptide ID homolog's for functional annotation, which increased the number of unigenes with GO terms assigned and resulted in more GO terms assigned per unigene. This allowed the identification of tissue-specific genes using enrichment analysis for GO pathways and protein domains. The comparative annotation approach represents a good strategy for transferring more relevant biological information from highly studied species to genomic resource poorer species. It was possible to confirm by interspecies mRNA-to-genomic alignments 25 and 21 alternative splice events in sea bream and sea bass genes, respectively. Even using normalized cDNA from relatively few pooled individuals it was possible to identify 1145 SNPs and 1748 microsatellites loci for genetic marker development.
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- 2010
15. Molecular cloning of Senegalese sole (Solea senegalensis) follicle-stimulating hormone and luteinizing hormone subunits and expression pattern during spermatogenesis
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Cerdà, Joan, Chauvigné, François, Agulleiro Gozalbo, Maria Josep, Marin, Elena, Halm, Silke, Martínez-Rodríguez, Gonzalo, Prat, Francisco, Cerdà, Joan, Chauvigné, François, Agulleiro Gozalbo, Maria Josep, Marin, Elena, Halm, Silke, Martínez-Rodríguez, Gonzalo, and Prat, Francisco
- Abstract
Pituitary gonadotropins (GTHs), follicle stimulating hormone (FSH) and luteinizing hormone (LH), are key regulators of vertebrate reproduction. However, in teleosts with testis of semi-cystic type and asynchronous spermatogenesis, as the flatfish Senegalese sole (Solea senegalensis), the physiological roles of FSH and LH are still not well understood. To gain insight into this mechanism, full-length complementary DNAs (cDNAs) encoding Senegalese sole FSHb and LHb subunits, and the common glycoprotein a subunit (CGa), were cloned and sequenced. The three cDNAs consisted of 550, 582 and 744 nucleotides encoding peptides of 120, 148 and 132 amino acids, respectively. Comparison of the deduced amino acid sequences of sole FSHb, LHb and CGa with those from other teleosts indicated that cysteine residues and potential N-linked glycosylation sites were fully conserved with respect to other percomorphs and salmonids. However, the primary structure of FSHb and LHb in pleuronectiforms appeared to be highly divergent. In situ hybridization of mature male pituitaries showed that fshb, lhb and cga mRNAs were localized in the proximal pars distalis and in the periphery of pars intermedia. Realtime quantitative reverse transcription-polymerase chain reaction indicated that the levels of all three transcripts in the pituitary of males increased during winter and spring, at the time when plasma levels of androgens raised and testicular germ cell development and spermatozoa production were stimulated. These results suggest that FSH and LH may regulate spermatogenesis in Senegalese sole similarly to that described for other teleosts with testis of cystic type and synchronous germ cell development.
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- 2008
16. Phylogenetic relationships and gene expression pattern of hree different cathepsin L (Ctsl) isoforms in zebrafish: Ctsla is the putative yolk processing enzyme
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Tingaud-Sequeira, Angèle, Cerdà, Joan, Tingaud-Sequeira, Angèle, and Cerdà, Joan
- Abstract
Certain cysteine proteases, such as cathepsin L (Ctsl), have been involved in yolk processing mechanisms in oocytes and embryos of lower vertebrates. In zebrafish (Danio rerio), three different ctsl genes, ctsla, ctslb and ctslc, have been found in the genome, but their pattern of expression, as well as information on which the encoded enzymes are potentially involved in yolk absorption during embryogenesis, is unknown. Here, phylogenetic and gene structure analysis revealed that zebrafish ctsla and ctslb genes are similar, showing a highly conserved structure in comparison with human ctsl, while ctslc presents different exon organization together with an earlier evolution. Thus, ctslc appears to be evolved from a common ancestral ctsl-like gene, possibly through an early duplication event, whereas ctsla and ctslb may be originated from a second duplication mechanism. Zebrafish ctsla, ctslb and ctslc also showed different patterns of mRNA expression during embryogenesis and in adult tissues. While Ctsla transcripts were accumulated in embryos throughout development and in the adult ovary, those encoding Ctslb were detected only in embryos around the time of hatching as previously reported, and those for Ctslc appeared only in larvae and in some adult tissues, but not in the ovary. In zebrafish and killifish (Fundulus heteroclitus) embryos, Ctsla mRNAwas first detected in blastomers, and later in development it was localized in cells of the yolk syncytial layer, an embryonic structure involved in yolk absorption. These data therefore suggested that Ctsla is most likely the putative protease involved in yolk processing in fish embryos, while Ctslc seems not to be required during early embryogenesis in zebrafish.
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- 2007
17. Yolk proteolysis and aquaporin-1o play essential roles to regulate fish oocyte hydration during meiosis resumption
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Fabra, Mercedes, Raldúa, Demetrio, Bozzo, María G., Deen, Peter M.T., Lubzens, Esther, Cerdà, Joan, Fabra, Mercedes, Raldúa, Demetrio, Bozzo, María G., Deen, Peter M.T., Lubzens, Esther, and Cerdà, Joan
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In marine fish, meiosis resumption is associated with a remarkable hydration of the oocyte, which contributes to the survival and dispersal of eggs and early embryos in the ocean. The accumulation of ions and the increase in free amino acids generated from the cleavage of yolk proteins (YPs) provide the osmotic mechanism for water influx into the oocyte, in which is involved the recently identified, fish specific aquaporin-1o (AQP1o). However, the timing when these processes occur during oocyte maturation, and the regulatory pathways involved, remain unknown. Here, we show that gilthead sea bream AQP1o (SaAQP1o) is synthesized at early vitellogenesis and transported towards the oocyte cortex throughout oocyte growth. During oocyte maturation, shortly after germinal vesicle breakdown and before complete hydrolysis of YPs and maximum K+ accumulation is reached, SaAQP1o is further translocated into the oocyte plasma membrane. Inhibitors of yolk proteolysis and SaAQP1o water permeability reduce sea bream oocyte hydration that normally accompanies meiotic maturation in vitro by 80% and 20%, respectively. Thus, yolk hydrolysis appears to play a major role to create the osmotic driving force, while SaAQP1o possibly facilitates water influx into the oocyte. These results provide further evidence for the role of AQP1o mediating water uptake into fish oocytes, and support a novel model of fish oocyte hydration, whereby the accumulation of osmotic effectors and AQP1o intracellular trafficking are two highly regulated mechanisms.
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- 2006
18. Evidence for involvement of chemical communication in reproduction of the eel Anguilla anguilla
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Huertas, Mar, Hubbard, Peter C., Canario, Adelino V. M., Cerdà, Joan, Scott, Alexander P., Huertas, Mar, Hubbard, Peter C., Canario, Adelino V. M., Cerdà, Joan, and Scott, Alexander P.
- Abstract
The European eel (Anguilla anguilla) is characterised by long transoceanic migration to spawning sites during which the fish become sexually mature. A previous study demonstrated that mature eels may induce physiological and behavioural changes in immature conspecifics. This raises the possibility that chemical communication may be involved in this process. The aim of the current study was, therefore, to assess the olfactory sensitivity of eels to conspecific-derived odours and to establish whether these odours differ according to sex and/or state of maturity. Solid-phase water extracts (using C18 cartridges), and bile and mucus samples, were collected from mature and immature fish of both sexes. Olfactory sensitivity to these samples was assessed by recording the electro-olfactogram (EOG) from immature males. Of the water extracts, those from spermiating males and pre-ovulatory females evoked the largest responses. Both bile and mucus proved to be highly potent odorants, evoking EOG responses at dilutions as low as 1:107 and 1:106 respectively. Cross-adaptation studies suggest that bile from males and females is qualitatively different and that mucus from mature and immature fish of both sexes is qualitatively and quantitatively different. Taken together, these results provide strong support for a role for chemical communication in this species, suggesting that a number of different odorants and routes of release may be involved. However, the chemical identities of these compounds and their exact biological roles remain to be elucidated
- Published
- 2005
19. Zebrafish vimentin: molecular characterization, assembly properties and developmental expression
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Cerdà, Joan, Conrad, Matthias, Markl, Jürgen, Brand, Michael, Herrmann, Harald, Cerdà, Joan, Conrad, Matthias, Markl, Jürgen, Brand, Michael, and Herrmann, Harald
- Abstract
To provide a basis for the investigation of the intermediate filament (IF) protein vimentin in one of the most promising experimental vertebrate systems, the zebrafish (Danio rerio), we have isolated a cDNA clone of high sequence identity to and with the characteristic features of human vimentin. Using this clone we produced recombinant zebrafish vimentin and studied its assembly behaviour. Unlike other vimentins, zebrafish vimentin formed unusually thick filaments when assembled at temperatures below 21°C. At 37°C few filaments were observed, which often also terminated in aggregated masses, indicating that its assembly was severely disturbed at this temperature. Between 21 and 34°C apparently normal IFs were generated. By viscometry, the temperature optimum of assembly was determined to be around 28°C. At this temperature, zebrafish vimentin partially rescued, in mixing experiments, the temperature-dependent assembly defect of trout vimentin. Therefore it is apparently able to "instruct" the misorganized trout vimentin such that it can enter normal IFs. This feature, that assembly is best at the normal body temperature of various species, puts more weight on the assumption that vimentin is vital for some aspects of generating functional adult tissues. Remarkably, like in most other vertebrates, zebrafish vimentin appears to be an abundant factor in the lens and the retina as well as transiently, during development, in various parts of the central and peripheral nervous system. Therefore, promising cell biological investigations may now be performed with cells involved in the generation of the vertebrate eye and brain, and, in particular, the retina. Moreover, the power of genetics of the zebrafish system may be employed to investigate functional properties of vimentin in vivo
- Published
- 1998
20. Evidence for the differential regulation of ovarian follicle responsiveness to human chorionic gonadotropin in vitro in a serranid teleost, Centropristis striata
- Author
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Cerdà, Joan, Selman, Kelly, Hsiao, Shyn-Min, Wallace, Robin A., Cerdà, Joan, Selman, Kelly, Hsiao, Shyn-Min, and Wallace, Robin A.
- Abstract
Pre-maturational or full-grown ovarian follicles were isolated from captive, spawning black sea bass, Centropristis striata, at different times during the spawning season and tested for their ability to undergo oocyte maturation in vitro in response to human chorionic gonadotropin (hCG). The gonadosomatic index (GSI) was greatest in females collected during the mid-spawning period and the number of abnormal (atretic) follicles in the ovary progressively increased throughout the spawning season. The maturational response of follicles induced by hCG generally declined as the spawning interval progressed; an increased inhibition of oocyte maturation by doses ≥ 50 IU ml−1 hCG was also observed. Linear regression analyses indicated that the percentage of inhibition of oocyte maturation by 50, 100 and 500 IU ml−1 hCG was positively correlated with increasing levels of atresia within the ovaries from which the follicles were isolated. In females with low incidence of ovarian atresia (0–5%), follicular maturation achieved with 1–10 IU ml−1 hCG positively correlated with the GSI. However, when follicles isolated from females with a GSI ≥ 8 were treated with 50–500 IU ml−1 hCG the maturational response of follicles was reduced in comparison with the maturation of follicles from females with lower GSI that were treated with the same doses of hCG. In addition, doses of 100 and 500 IU ml−1 hCG appeared to be inhibitory on oocyte maturation once the GSI ≥ 8. These results suggest that the sensitivity of C. striata pre-maturational follicles to gonadotropin (GtH) may be regulated differently depending on both the overall state of follicular development and the levels of atresia within the ovary; the desensitization of GtH receptors may be one of the mechanisms possibly involved. It is recommended that the specific physiological condition of the ovary must be considered in selecting the timing and the dose of hCG to induce ovulation in this species
- Published
- 1997
21. Functional Heterologous Gap Junctions in Fundulus Ovarian Follicles Maintain Meiotic Arrest and Permit Hydration during Oocyte Maturation
- Author
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Cerdà, Joan, Petrino, Teresa R., Wallace, Robin A., Cerdà, Joan, Petrino, Teresa R., and Wallace, Robin A.
- Abstract
The physiological significance of heterologous gap junctions between granulosa cells and the oocyte was investigated in late vitellogenic ovarian follicles of the teleost Fundulus heteroclitus. Lucifer Yellow injected into the oocyte readily passed to the overlying granulosa cells, demonstrating effective dye-coupling. Passage of the fluorescent dye, and hence intercellular communication, was inhibited both by the tumor-promoting phorbol ester phorbol 12-myristate 13-acetate (PMA) and by 1-octanol, known uncouplers of gap junctions in a variety of invertebrate and vertebrate cell types. Octanol alone also initiated resumption of meiosis in follicle-enclosed oocytes, indicating that granulosa cells normally maintain meiotic arrest, as apparently occurs in mammalian and amphibian follicles. Both PMA and octanol also consistently inhibited the hydration process that normally accompanies meiotic maturation. These results support a previously suggested hypothesis that K+, which is the primary osmotic effector for oocyte hydration, is translocated via gap junctions from granulosa cells to the maturing oocyte
- Published
- 1993
22. Short-term polystyrene nanoplastic exposure alters zebrafish male and female germline and reproductive outcomes, unveiling pollutant-impacted molecular pathways.
- Author
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Pujol G, Marín-Gual L, González-Rodelas L, Álvarez-González L, Chauvigné F, Cerdà J, Teles M, Roher N, and Ruiz-Herrera A
- Abstract
Nanoplastics pollution is a rising environmental concern whose impacts on biodiversity and human health are far from being understood. This is particularly salient in aquatic ecosystems, where the majority of species depend on external fertilization for reproduction. Here we evaluated the effects of a short-term exposure to engineered polystyrene nanoplastics (NPs) in the zebrafish germline to further explore their impact on reproduction. To this end, zebrafish (Danio rerio) were exposed to 5 mg/L of 45 nm polystyrene (PS)-NPs via water for 96 h. We show that, in males, nanoplastics induced testicular histological alterations with abnormal sperm clustering and chromatin compaction, resulting in viable spermatozoa but with reduced motility. Moreover, in females we observed an alteration in oocyte stages frequencies during oogenesis, possibly reflecting alterations in oocyte growth. RNA-sequencing analysis in male testis links nanoplastic induced alterations in the expression of genes involved in chromatin structure, meiosis and DNA double-strand break formation and repair progression, and gametes recognition. Flow cytometry analysis revealed that the observed effects in males were directly due to nanoplastics penetrating the testicular barrier and being internalized within germline cells. Overall, our results demonstrate that acute exposure to NPs can compromise reproductive fitness, underscoring the environmental and health impacts of NPs pollution., 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 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
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23. Primary oocyte transcriptional activation of aqp1ab by the nuclear progestin receptor determines the pelagic egg phenotype of marine teleosts.
- Author
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Zapater C, Chauvigné F, Tingaud-Sequeira A, Finn RN, and Cerdà J
- Subjects
- Analysis of Variance, Animals, Aquaporin 1 biosynthesis, Aquaporin 1 genetics, Base Sequence, Bayes Theorem, Chromatin Immunoprecipitation, DNA Primers genetics, Humans, Hydroxyprogesterones metabolism, Immunoblotting, In Situ Hybridization, Likelihood Functions, Luciferases, MCF-7 Cells, Microscopy, Fluorescence, Models, Genetic, Molecular Sequence Data, Mutagenesis, Site-Directed, Phylogeny, Promoter Regions, Genetic genetics, Real-Time Polymerase Chain Reaction, Reverse Transcriptase Polymerase Chain Reaction, SOX9 Transcription Factor metabolism, Sea Bream metabolism, Sequence Analysis, DNA, Aquaporin 1 metabolism, Gene Expression Regulation, Developmental genetics, Oocytes metabolism, Phenotype, Receptors, Progesterone metabolism, Sea Bream embryology, Zygote cytology
- Abstract
In marine teleosts, the aqp1ab water channel plays a vital role in the development of the pelagic egg phenotype. However, the developmental control of aqp1ab activation during oogenesis remains to be established. Here, we report the isolation of the 5'-flanking region of the teleost gilthead seabream aqp1ab gene, in which we identify conserved cis-regulatory elements for the binding of the nuclear progestin receptor (Pgr) and members of the Sox family of transcription factors. Subcellular localization studies indicated that the Pgr, as well as sox3 and -8b transcripts, are co-expressed in seabream oogonia, whereas in meiosis-arrested primary growth (pre-vitellogenic) oocytes, when aqp1ab mRNA and protein are first synthesized, the Pgr appears to be completely translocated from the ooplasm into the nucleus. By contrast, sox9b is highly expressed in more advanced oocytes, coinciding with a strong depletion of aqp1ab transcripts in the oocyte. Functional characterization of wild-type and mutated aqp1ab promoter constructs, using mammalian cells and Xenopus laevis oocytes, demonstrated that aqp1ab transcription is initiated by the Pgr, which is activated by the progestin 17α,20β-dihydroxy-4-pregnen-3-one (17,20β-P), the natural ligand of the seabream Pgr. In vitro incubation of seabream primary ovarian explants with the follicle-stimulating hormone or 17,20β-P confirmed that progestin-activated Pgr enhanced Aqp1ab synthesis via the aqp1ab promoter. However, transactivation assays in heterologous systems showed that Sox transcription factors can potentially modulate this mechanism. These data uncover the existence of an endocrine pathway involved in the early activation of a water channel necessary for egg formation in marine teleosts., (Copyright © 2013 Elsevier Inc. All rights reserved.)
- Published
- 2013
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24. Gilthead sea bream (Sparus auratus) and European sea bass (Dicentrarchus labrax) expressed sequence tags: Characterization, tissue-specific expression and gene markers.
- Author
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Louro B, Passos AL, Souche EL, Tsigenopoulos C, Beck A, Lagnel J, Bonhomme F, Cancela L, Cerdà J, Clark MS, Lubzens E, Magoulas A, Planas JV, Volckaert FA, Reinhardt R, and Canario AV
- Abstract
The gilthead sea bream, Sparus auratus, and the European sea bass, Dicentrarchus labrax, are two of the most important marine species cultivated in Southern Europe. This study aimed at increasing genomic resources for the two species and produced and annotated two sets of 30,000 expressed sequence tags (EST) each from 14 normalized tissue-specific cDNA libraries from sea bream and sea bass. Clustering and assembly of the ESTs formed 5268 contigs and 12,928 singletons for sea bream and 4573 contigs and 13,143 singletons for sea bass, representing 18,196 and 17,716 putative unigenes, respectively. Assuming a similar number of genes in sea bass, sea bream and in the model fish Gasterosteus aculeatus genomes, it was estimated that approximately two thirds of the sea bream and the sea bass transcriptomes were covered by the unigene collections. BLAST sequence similarity searches (using a cut off of e-value <10(-5)) against fully the curated SwissProt (and TrEMBL) databases produced matches of 28%(37%) and 43%(53%) of the sea bream and sea bass unigene datasets respectively, allowing some putative designation of function. A comparative approach is described using human Ensembl peptide ID homolog's for functional annotation, which increased the number of unigenes with GO terms assigned and resulted in more GO terms assigned per unigene. This allowed the identification of tissue-specific genes using enrichment analysis for GO pathways and protein domains. The comparative annotation approach represents a good strategy for transferring more relevant biological information from highly studied species to genomic resource poorer species. It was possible to confirm by interspecies mRNA-to-genomic alignments 25 and 21 alternative splice events in sea bream and sea bass genes, respectively. Even using normalized cDNA from relatively few pooled individuals it was possible to identify 1145 SNPs and 1748 microsatellites loci for genetic marker development. The EST data are being applied to a range of projects, including the development microarrays, genetic and radiation hybrid maps and QTL genome scans. This highlights the important role of ESTs for generating genetic and genomic resources of aquaculture species., (Copyright © 2010 Elsevier B.V. All rights reserved.)
- Published
- 2010
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25. Yolk proteolysis and aquaporin-1o play essential roles to regulate fish oocyte hydration during meiosis resumption.
- Author
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Fabra M, Raldúa D, Bozzo MG, Deen PM, Lubzens E, and Cerdà J
- Subjects
- Animals, Aquaporin 1 antagonists & inhibitors, Egg Yolk drug effects, Female, Gene Expression Regulation, Potassium metabolism, Protein Transport, Sodium metabolism, Tetraethylammonium pharmacology, Water metabolism, Aquaporin 1 physiology, Egg Yolk metabolism, Meiosis, Oocytes physiology, Sea Bream physiology
- Abstract
In marine fish, meiosis resumption is associated with a remarkable hydration of the oocyte, which contributes to the survival and dispersal of eggs and early embryos in the ocean. The accumulation of ions and the increase in free amino acids generated from the cleavage of yolk proteins (YPs) provide the osmotic mechanism for water influx into the oocyte, in which is involved the recently identified, fish specific aquaporin-1o (AQP1o). However, the timing when these processes occur during oocyte maturation, and the regulatory pathways involved, remain unknown. Here, we show that gilthead sea bream AQP1o (SaAQP1o) is synthesized at early vitellogenesis and transported towards the oocyte cortex throughout oocyte growth. During oocyte maturation, shortly after germinal vesicle breakdown and before complete hydrolysis of YPs and maximum K(+) accumulation is reached, SaAQP1o is further translocated into the oocyte plasma membrane. Inhibitors of yolk proteolysis and SaAQP1o water permeability reduce sea bream oocyte hydration that normally accompanies meiotic maturation in vitro by 80% and 20%, respectively. Thus, yolk hydrolysis appears to play a major role to create the osmotic driving force, while SaAQP1o possibly facilitates water influx into the oocyte. These results provide further evidence for the role of AQP1o mediating water uptake into fish oocytes, and support a novel model of fish oocyte hydration, whereby the accumulation of osmotic effectors and AQP1o intracellular trafficking are two highly regulated mechanisms.
- Published
- 2006
- Full Text
- View/download PDF
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