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1.
Rev. biol. trop ; 72(supl.1): e59013, Mar. 2024. tab, graf
Article Dans Anglais | LILACS, SaludCR | ID: biblio-1559343

Résumé

Abstract Introduction: Short-term gametes storage is an inexpensive and simple technique that allows the use of the same batch of eggs or sperm at different times, maximizing the application of research protocols and the use of gametes in production. Arbacia dufresnii is a sea urchin species with proven aquaculture potential and already used in the nutraceutical industry. Aging of its gametes is unknown and is a needed information to scale up the production. Objective: Determine the effect of male and female gamete aging on the fertilization success of Arbacia dufresnii. This will allow optimizing the use of gametes after collection decoupling spawning from fertilization. Methods: A. dufresnii individuals were induced to spawn and gametes were kept at 12 ± 1 °C throughout each bioassay. Sperm was separated into two treatments: activated sperm in seawater (AS), and dry sperm (DS). Two bioassays were made: Bioassay 1 evaluated the effect of time on fertility by performing fertilization tests at 0 h, 24 h, 48 h, 72 h, and 96 h after spawning. Bioassay 2 evaluated the contribution of each type of aged gamete on fertility, combining aged gametes (96 h) with fresh gametes (0 h). Results: Bioassay 1: the fertilization success obtained by combining eggs (E) with AS or DS presented important differences. While the fertilization success remained acceptable (greater than 50 %) for up to 72 h using ExDS, it only remained acceptable for up to 48 h using ExAS. Bioassay 2: acceptable fertilization success was found by combining aged E (96 h) with fresh sperm, or aged DS (96 h) with fresh E, but not using aged AS with fresh E. Conclusions: The findings of this work show that fertilization success in A. dufresnii gametes remains relatively unchanged for up to 48 h after spawning when combining ExAS, and for up to 72 h when combining ExDS. However, when combining aged E or aged DS with a fresh gamete, post-collection fertilization can be extended up to 96 h. In this work, the first steps have been taken to understand the conservation time of A. dufresnii gametes with minimum intervention.


Resumen Introducción: El almacenamiento de gametos a corto plazo es una técnica económica y sencilla que permite utilizar el mismo lote de óvulos o espermatozoides en diferentes momentos, maximizando la aplicación de protocolos de investigación y el uso de gametos en la producción. Arbacia dufresnii es una especie con probado potencial acuícola como fuente de gametos para la industria nutracéutica. Sin embargo, se desconoce el envejecimiento de sus gametos y es una información necesaria para escalar la producción. Objetivo: Determinar el efecto del envejecimiento de los gametos masculinos y femeninos en el éxito de la fecundación de Arbacia dufresnii con el fin de optimizar el aprovechamiento de los gametos después de la recolecta desincronizando el desove de la fecundación. Métodos: Se indujo el desove de individuos de A. dufresnii y los gametos se mantuvieron a 12 ± 1 °C durante cada bioensayo. El esperma se separó en dos tratamientos: esperma activado en agua de mar (AS) y esperma seco (DS). Se realizaron dos bioensayos: El Bioensayo 1 evaluó el efecto del tiempo sobre la fertilidad realizando pruebas de fecundación a las 0 h, 24 h, 48 h, 72 h y 96 h después del desove. El bioensayo 2 evaluó la contribución de cada tipo de gameta envejecida (96 h) sobre la fertilidad, combinando gametos envejecidas (96 h) con gametos frescas (0 h). Resultados: Bioensayo 1: el éxito de fecundación obtenido combinando huevos (E) con AS o DS presentó diferencias importantes. Si bien el éxito de la fecundación se mantuvo aceptable (más del 50 %) durante un máximo de 72 h con ExDS, solo permaneció aceptable hasta 48 h con ExAS. Bioensayo 2: se encontró un éxito de fecundación aceptable combinando E envejecidos (96 h) con esperma fresco, o DS envejecido (96 h) con E fresco (0 h), pero no usando AS envejecido con E fresco (0 h). Conclusiones: Los hallazgos de este trabajo muestran que el éxito de la fecundación en los gametos de A. dufresnii permanece relativamente sin cambios hasta 48 h después del desove cuando se combina ExAS, y hasta 72 h cuando se combina ExDS. Sin embargo, cuando se combina E envejecido o DS envejecido con un gameto fresco, el tiempo entre la recolección y la fecundación puede extenderse hasta 96 h. En este trabajo se han dado los primeros pasos para entender el tiempo de conservación de los gametos de A. dufresnii con mínima intervención.


Sujets)
Animaux , Reproduction , Echinoidea/embryologie , Dosage biologique , Echinodermata/croissance et développement , Cellules germinales/croissance et développement
2.
Rev. biol. trop ; 72(supl.1): e58995, Mar. 2024. tab, graf
Article Dans Anglais | LILACS, SaludCR | ID: biblio-1559337

Résumé

Abstract Introduction: Care towards nutrition is essential for the quality of a sustainable aquaculture product. Since the balance in food affects the growth and production of gametes. The circular economy is made possible through the use of discarded materials. Objective: The aim of this research was to study the fatty acid composition and metabolic pathways in the gametes of Arbacia dufresnii, with a focus on the implications of incorporating shrimp byproducts into aquaculture feeds. Methods: Four different treatments were designed to maintain optimal nutritional quality, particularly in lipids and proteins, based on previous studies. The fatty acid profiles of the feeds and gametes were analyzed by using gas-chromatography, and statistical analyses were conducted to determine significant differences. Results: Significant differences were observed in the abundance (%) of omega-3 (ω-3) and omega-6 (ω-6) fatty acids. The (ω-3) metabolic pathway was more pronounced in the gametes of wild animals and those fed with the experimental feeds. In contrast, the (ω-6) metabolic pathway was less relevant in these groups. The (ω-3) /(ω-6) ratio was highest in the gametes of wild animals. Feeds enriched in fatty acids enhanced their bioaccumulation in the gametes reaching higher concentrations than wild animals. The availability of fatty acids in foods allowed their bioaccumulation in gametes, with concentrations equal to or higher than those observed in animals in their natural environment for certain fatty acids. Conclusions: Incorporating shrimp byproducts in aquaculture feeds demonstrated a promising strategy for resource utilization and organic input generation. The fatty acid composition in the gametes of A. dufresnii was influenced by the diet, highlighting the potential of balanced feeds to enhance the bioaccumulation of essential fatty acids. These findings provide valuable insights for the development of sustainable aquaculture practices and the production of nutritionally enriched seafood products.


Resumen Introducción: El cuidado hacia la nutrición es fundamental para la calidad de un producto acuícola sostenible. Ya que el balance en los alimentos afecta el crecimiento y producción de los gametos. A partir del aprovechamiento de materias de descarte se posibilita la economía circular. Objetivo: El objetivo de este estudio fue investigar la composición de ácidos grasos y las vías metabólicas en los gametos de Arbacia dufresnii, centrándose en las implicaciones de la incorporación de subproductos de camarones en los alimentos de acuicultura. Métodos: Se diseñaron cuatro tratamientos diferentes para mantener una calidad nutricional óptima, especialmente en lípidos y proteínas, basándose en estudios previos. Se analizaron los perfiles de ácidos grasos de los alimentos y los gametos mediante cromatografía de gases, y se realizaron análisis estadísticos para determinar diferencias significativas. Resultados: Se observaron diferencias significativas en la abundancia (%) de ácidos grasos omega-3 (ω-3) y omega-6 (ω-6). La vía metabólica de (ω-3) fue más pronunciada en los gametos de los animales en su entorno natural y aquellos alimentados con los piensos experimentales. Por el contrario, la vía metabólica de (ω-6) tuvo menos relevancia en estos grupos. La relación (ω-3) /(ω-6) fue más alta en los gametos de los animales en su entorno natural. La disponibilidad de ácidos grasos en los alimentos permitió su bioacumulación en los gametos, con concentraciones iguales o superiores a las observadas en los animales en su entorno natural para ciertos ácidos grasos. Conclusiones: La incorporación de subproductos de camarones en los alimentos de acuicultura demostró ser una estrategia prometedora para la utilización de recursos y la generación de insumos orgánicos. La composición de ácidos grasos en los gametos de A. dufresnii fue influenciada por la dieta, destacando el potencial de los alimentos balanceados para mejorar la bioacumulación de ácidos grasos esenciales. Estos hallazgos brindan información valiosa para el desarrollo de prácticas sostenibles en acuicultura y la producción de productos marinos enriquecidos nutricionalmente.


Sujets)
Animaux , Arbacia/croissance et développement , Voies et réseaux métaboliques , Acides gras/analyse , Cellules germinales/microbiologie , Echinoidea/croissance et développement , Aquaculture , Astacoidea
3.
Chinese Journal of Biotechnology ; (12): 4219-4233, 2023.
Article Dans Chinois | WPRIM | ID: wpr-1008022

Résumé

This study aimed to explore the expression changes of VASA gene in sheep testis development and to construct VASA gene knock-in vector to prepare for the study on the differentiation of sheep germ cells in vitro. The testicular tissues of 3-month-old (3M) and 9-month-old (9M) sheep which represent immature and mature stages, respectively, were collected. The differential expression of VASA gene was analyzed by quantitative real-time PCR (qPCR) and Western blotting, and the location of VASA gene was detected by immunohistochemistry. The sgRNA targeting the VASA gene was designed and homologous recombination vectors were constructed by PCR. Subsequently, plasmids were transferred into sheep ear fibroblasts. The VASA gene was activated in combination with CRISPR/dCas9 technology to further verify the efficiency of the vector. The results showed that the expression level of VASA gene increased significantly with the development of sheep testis (P < 0.01), and was mainly located in spermatocytes and round spermatids. The knock-in vector of VASA gene was constructed by CRISPR/Cas9 system, and the Cas9-gRNA vector and pEGFP-PGK puro-VASA vector were transfected into ear fibroblasts. After CRISPR/dCas9 system was activated, ear fibroblasts successfully expressed VASA gene. The results suggest that VASA gene plays a potential function in sheep testicular development and spermatogenesis, and the VASA gene knock-in vector can be constructed in vitro through the CRISPR/Cas9 system. Our results provided effective research tools for further research of germ cell development and differentiation.


Sujets)
Mâle , Animaux , Ovis/génétique , Systèmes CRISPR-Cas/génétique , Techniques de knock-in de gènes , , Plasmides , Cellules germinales
4.
Asian Journal of Andrology ; (6): 13-20, 2023.
Article Dans Anglais | WPRIM | ID: wpr-970987

Résumé

Infertility has become a serious disease since it affects 10%-15% of couples worldwide, and male infertility contributes to about 50% of the cases. Notably, a significant decrease occurs in the newborn population by 7.82 million in 2020 compared to 2016 in China. As such, it is essential to explore the effective methods of obtaining functional male gametes for restoring male fertility. Stem cells, including embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), spermatogonial stem cells (SSCs), and mesenchymal stem cells (MSCs), possess the abilities of both self-renewal and differentiation into germ cells. Significantly, much progress has recently been achieved in the generation of male germ cells in vitro from various kinds of stem cells under the specified conditions, e.g., the coculturing with Sertoli cells, three-dimensional culture system, the addition of growth factors and cytokines, and/or the overexpression of germ cell-related genes. In this review, we address the current advance in the derivation of male germ cells in vitro from stem cells based on the studies of the peers and us, and we highlight the perspectives and potential application of stem cell-derived male gametes in reproductive medicine.


Sujets)
Humains , Nouveau-né , Mâle , Cellules germinales , Cellules souches embryonnaires , Différenciation cellulaire , Infertilité masculine , Cellules souches pluripotentes induites
5.
Protein & Cell ; (12): 477-496, 2023.
Article Dans Anglais | WPRIM | ID: wpr-982528

Résumé

Although somatic cells can be reprogrammed to pluripotent stem cells (PSCs) with pure chemicals, authentic pluripotency of chemically induced pluripotent stem cells (CiPSCs) has never been achieved through tetraploid complementation assay. Spontaneous reprogramming of spermatogonial stem cells (SSCs) was another non-transgenic way to obtain PSCs, but this process lacks mechanistic explanation. Here, we reconstructed the trajectory of mouse SSC reprogramming and developed a five-chemical combination, boosting the reprogramming efficiency by nearly 80- to 100-folds. More importantly, chemical induced germline-derived PSCs (5C-gPSCs), but not gPSCs and chemical induced pluripotent stem cells, had authentic pluripotency, as determined by tetraploid complementation. Mechanistically, SSCs traversed through an inverted pathway of in vivo germ cell development, exhibiting the expression signatures and DNA methylation dynamics from spermatogonia to primordial germ cells and further to epiblasts. Besides, SSC-specific imprinting control regions switched from biallelic methylated states to monoallelic methylated states by imprinting demethylation and then re-methylation on one of the two alleles in 5C-gPSCs, which was apparently distinct with the imprinting reprogramming in vivo as DNA methylation simultaneously occurred on both alleles. Our work sheds light on the unique regulatory network underpinning SSC reprogramming, providing insights to understand generic mechanisms for cell-fate decision and epigenetic-related disorders in regenerative medicine.


Sujets)
Mâle , Souris , Animaux , Reprogrammation cellulaire/génétique , Tétraploïdie , Cellules souches pluripotentes/métabolisme , Cellules souches pluripotentes induites/métabolisme , Méthylation de l'ADN , Spermatogonies/métabolisme , Cellules germinales/métabolisme
6.
Biol. Res ; 56: 19-19, 2023. ilus, graf, tab
Article Dans Anglais | LILACS | ID: biblio-1439486

Résumé

BACKGROUND: AMBRA1 is an intrinsically disordered protein, working as a scaffold molecule to coordinate, by protein-protein interaction, many cellular processes, including autophagy, mitophagy, apoptosis and cell cycle progression. The zebrafish genome contains two ambra1 paralogous genes (a and b), both involved in development and expressed at high levels in the gonads. Characterization of the zebrafish paralogous genes mutant lines generated by CRISPR/Cas9 approach showed that ambra1b knockout leads to an all-male population. RESULTS: We demonstrated that the silencing of the ambra1b gene determines a reduction of primordial germ cells (PGCs), a condition that, in the zebrafish, leads to the development of all-male progeny. PGC reduction was confirmed by knockdown experiments and rescued by injection of ambra1b and human AMBRA1 mRNAs, but not ambra1a mRNA. Moreover, PGC loss was not rescued by injection with human AMBRA1 mRNA mutated in the CUL4-DDB1 binding region, thus suggesting that interaction with this complex is involved in PGC protection from loss. Results from zebrafish embryos injected with murine Stat3 mRNA and stat3 morpholino suggest that Ambra1b could indirectly regulate this protein through CUL4-DDB1 interaction. According to this, Ambra1+/- mice showed a reduced Stat3 expression in the ovary together with a low number of antral follicles and an increase of atretic follicles, indicating a function of Ambra1 in the ovary of mammals as well. Moreover, in agreement with the high expression of these genes in the testis and ovary, we found significant impairment of the reproductive process and pathological alterations, including tumors, mainly limited to the gonads. CONCLUSIONS: By exploiting ambra1a and ambra1b knockout zebrafish lines, we prove the sub-functionalization between the two paralogous zebrafish genes and uncover a novel function of Ambra1 in the protection from excessive PGC loss, which seems to require binding with the CUL4-DDB1 complex. Both genes seem to play a role in the regulation of reproductive physiology.


Sujets)
Humains , Animaux , Mâle , Femelle , Souris , Différenciation sexuelle , Danio zébré/génétique , Danio zébré/métabolisme , Reproduction , ARN messager/métabolisme , Protéines de poisson-zèbre/génétique , Protéines de poisson-zèbre/métabolisme , Protéines adaptatrices de la transduction du signal/métabolisme , Cellules germinales/métabolisme , Mammifères/génétique , Mammifères/métabolisme
7.
Arch. endocrinol. metab. (Online) ; 66(1): 104-111, Jan.-Feb. 2022. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1364312

Résumé

SUMMARY We present the unique case of an adult Brazilian woman with severe short stature due to growth hormone deficiency with a heterozygous G to T substitution in the donor splice site of intron 3 of the growth hormone 1 (GH1) gene (c.291+1G>T). In this autosomal dominant form of growth hormone deficiency (type II), exon 3 skipping results in expression of the 17.5 kDa isoform of growth hormone, which has a dominant negative effect over the bioactive isoform, is retained in the endoplasmic reticulum, disrupts the Golgi apparatus, and impairs the secretion of other pituitary hormones in addition to growth hormone deficiency. This mechanism led to the progression of central hypothyroidism in the same patient. After 5 years of growth and thyroid hormone replacement, at the age of 33, laboratory evaluation for increased weight gain revealed high serum and urine cortisol concentrations, which could not be suppressed with dexamethasone. Magnetic resonance imaging of the sella turcica detected a pituitary macroadenoma, which was surgically removed. Histological examination confirmed an adrenocorticotropic hormone (ACTH)-secreting pituitary macroadenoma. A ubiquitin-specific peptidase 8 (USP8) somatic pathogenic variant (c.2159C>G/p.Pro720Arg) was found in the tumor. In conclusion, we report progression of isolated growth hormone deficiency due to a germline GH1 variant to combined pituitary hormone deficiency followed by hypercortisolism due to an ACTH-secreting macroadenoma with a somatic variant in USP8 in the same patient. Genetic studies allowed etiologic diagnosis and prognosis of this unique case.


Sujets)
Humains , Femelle , Adulte , Hormone de croissance humaine , Hypersécrétion hypophysaire d'ACTH , Nanisme hypophysaire/génétique , Endopeptidases/génétique , Ubiquitin thiolesterase/génétique , Complexes de tri endosomique requis pour le transport/génétique , Cellules germinales , Mutation
8.
Frontiers of Medicine ; (4): 459-466, 2022.
Article Dans Anglais | WPRIM | ID: wpr-939879

Résumé

Whether Fanconi anemia (FA) heterozygotes are predisposed to bone marrow failure and hematologic neoplasm is a crucial but unsettled issue in cancer prevention and family consulting. We retrospectively analyzed rare possibly significant variations (PSVs) in the five most obligated FA genes, BRCA2, FANCA, FANCC, FANCD2, and FANCG, in 788 patients with aplastic anemia (AA) and hematologic malignancy. Sixty-eight variants were identified in 66 patients (8.38%). FANCA was the most frequently mutated gene (n = 29), followed by BRCA2 (n = 20). Compared with that of the ExAC East Asian dataset, the overall frequency of rare PSVs was higher in our cohort (P = 0.016). BRCA2 PSVs showed higher frequency in acute lymphocytic leukemia (P = 0.038), and FANCA PSVs were significantly enriched in AA and AML subgroups (P = 0.020; P = 0.008). FA-PSV-positive MDS/AML patients had a higher tumor mutation burden, higher rate of cytogenetic abnormalities, less epigenetic regulation, and fewer spliceosome gene mutations than those of FA-PSV-negative MDS/AML patients (P = 0.024, P = 0.029, P = 0.024, and P = 0.013). The overall PSV enrichment in our cohort suggests that heterozygous mutations of FA genes contribute to hematopoietic failure and leukemogenesis.


Sujets)
Humains , Anémie aplasique/génétique , Épigenèse génétique , Anémie de Fanconi/génétique , Cellules germinales , Tumeurs hématologiques/génétique , Leucémie aigüe myéloïde/génétique , Études rétrospectives
9.
Article Dans Chinois | WPRIM | ID: wpr-928413

Résumé

OBJECTIVE@#To explore the genetic basis for a male with breast cancer and a sister who had deceased of the disease.@*METHODS@#Medical and family history of the proband was collected. Next-generation sequencing was carried out to detect potential variant associated with breast cancer, and Sanger sequencing was used to verify the result.@*RESULTS@#The proband was found to harbor a novel heterozygous c.6018dupT variant of the BRCA2 gene which may cause premature termination of mRNA translation, resulting in a truncated protein. Combined with the family history, the variant was deduced to be a germline mutation. Based on the American College of Medical Genetics and Genomics standards and guidelines, c.6018dupT variant of BRCA2 gene was predicted to be pathogenic (PVS1+PM1/2+PP4).@*CONCLUSION@#The germline variant of the BRCA2 gene probably underlay the breast cancer in this pedigree.


Sujets)
Humains , Mâle , Protéine BRCA2/génétique , Tumeur du sein de l'homme/génétique , Gène BRCA2 , Génomique , Cellules germinales , Mutation germinale
11.
Acta toxicol. argent ; 29(2): 1-10, dic. 2021. graf
Article Dans Espagnol | LILACS | ID: biblio-1364280

Résumé

Resumen El consumo crónico de alcohol es un problema de salud mundial que afecta particularmente a la población femenina. Sin embargo, los efectos de la ingesta semicrónica en cantidades moderadas a bajas en el ovario y el oocito son poco conocidos. En un modelo murino, se administró etanol al 10% en agua de bebida (hembras tratadas) o agua (hembras control) por 15 días, y luego de la superovulación o no (ovulación espontánea), se analizó el ciclo estral y la calidad ovárico-gamética. En las hembras tratadas, la frecuencia y duración del diestro aumentó, y las frecuencias de folículos y cuerpos lúteos disminuyeron vs hembras controles, valores que se restauraron luego de la superovulación. Sin embargo, en las hembras tratadas, la tasa de proliferación celular folicular y el desbalance de la expresión ovárica de VEGF (factor de crecimiento endotelial) persistieron luego de la superovulación. El número de ovocitos ovulados con metafase II anormal, fragmentados y activados partenogenéticamente fue mayor en las hembras tratadas respecto las controles. En conclusión, el consumo semicrónico moderado de alcohol produce anestro, ciclo estral irregular, foliculogénesis deficiente y anomalías núcleo-citoplasmáticas en los oocitos ovulados. Estas alteraciones podrían constituirse en un factor etiológico de pérdida gestacional temprana y desarrollo embrionario anormal luego del consumo de alcohol.


Abstract Chronic alcohol consumption is a global health problem that particularly affects the female population. However, the ef-fects of semi-chronic ethanol intake in low-moderate amounts on the ovary and oocyte are poorly understood. In a mouse model, 10% ethanol was administered in drinking water (treated females) or water (control females) for 15 days, and after superovulation or not (spontaneous ovulation), the estrous cycle and ovarian-gametic quality were analyzed. In treated females, the frequency and duration of the diestrus increased, and the frequencies of follicles and corpus luteum decreased vs control females, values that restored after superovulation. However, in treated females, the follicular cell proliferation rate and the imbalance in ovarian expression of VEGF (endothelial growth factor) persisted after superovulation. The number of ovulated oocytes with abnormal metaphase II, fragmented and parthenogenetically activated was higher in treated females than in control ones. In conclusion, moderate semi-chronic alcohol consumption produces anestrum, irregular estrous cycle, poor folliculogenesis, and nuclear-cytoplasmic abnormalities in ovulated oocytes. These alterations could constitute an etiological factor of early gestational loss and abnormal embryonic development after alcohol consumption.


Sujets)
Humains , Animaux , Femelle , Souris , Ovocytes/effets des médicaments et des substances chimiques , Consommation d'alcool/effets indésirables , Éthanol/effets indésirables , Follicule ovarique/effets des médicaments et des substances chimiques , Ovaire/cytologie , Ovaire/effets des médicaments et des substances chimiques , Oviductes/cytologie , Oviductes/effets des médicaments et des substances chimiques , Ovulation/effets des médicaments et des substances chimiques , Modèles animaux , Cycle oestral/effets des médicaments et des substances chimiques , Prolifération cellulaire , Cellules germinales/cytologie , Cellules germinales/effets des médicaments et des substances chimiques , Follicule ovarique/cytologie
12.
Rev. colomb. cancerol ; 25(2): 79-92, ene.-jun. 2021. tab, graf
Article Dans Espagnol | LILACS | ID: biblio-1376831

Résumé

Resumen Los tumores de células germinales (TCG) son las neoplasias malignas más comunes y afectan especialmente a hombres jóvenes de 15 a 35 años de edad. Los pacientes con estadios 2 y 3 que recaen ofrecen un gran reto para el tratamiento inicial de la primera recaída. La terapia óptima para estos pacientes depende de su tratamiento inicial y está pobremente definida. Las opciones incluyen regímenes de segunda línea de quimioterapia a dosis convencionales que combinan cisplatino e ifosfamida, con vinblastina, etopósido o paclitaxel, o quimioterapia de altas dosis con soporte de células madre. En vista de que todavía no hay evidencia concluyente en los ensayos clínicos, las indicaciones para el uso de quimioterapia de altas dosis permanecen poco claras y se basan en estudios fundamentalmente retrospectivos. El tratamiento en la segunda recaída debe individualizarse según el paciente y el tratamiento previo. La resección quirúrgica de masas residuales luego de la quimioterapia es un elemento clave para una terapia exitosa en pacientes con marcadores tumorales negativos. Actualmente, en Venezuela los pacientes que presentan recaídas deben recibir tratamiento con cualquiera de los regímenes establecidos que se utilizan a dosis convencionales en segunda línea. En algunos casos, los pacientes deben recibir tratamiento en centros de oncología con un manejo multidisciplinario que permita el acceso a tratamiento con altas dosis de quimioterapia y a cirujanos oncólogos expertos en esta patología.


Abstract Germ cell tumors (GCT) are the most common malignant neoplasms affecting young men aged 15 to 35 years. Patients with previous stage 2 and 3 who relapse offer a great challenge to the Medical team. The optimal therapy for these patients with recurrent disease is still poorly defined. Options include second-line chemotherapy regimens at conventional doses which combine cisplatin and ifosfamide, with vinblastine, etoposide or paclitaxel, or alternatively high-dose chemotherapy with stem cell support. As there is still no conclusive evidence from clinical trials, the indications for the use of high-dose chemotherapy remain unclear. Most of the present literature is based in retrospective studies. Second relapse treatment options should be individualized according to the patient and his previous treatment. Surgical resection of residual masses in patients with negative markers after chemotherapy is a key element for successful therapy. Currently, patients in Venezuela who have relapses should receive treatment with any of the established regimens that are used at conventional doses in the second line, however in some cases they should receive treatment in an oncology center with a multidisciplinary team having access to treatment with high dose chemotherapy and to oncologist surgeons who are experts in this area.


Sujets)
Humains , Mâle , Thérapeutique , Tumeurs embryonnaires et germinales , Dosage , Cellules germinales
13.
Acta bioeth ; 27(1): 69-78, jun. 2021.
Article Dans Anglais | LILACS | ID: biblio-1383247

Résumé

Abstract: 15. The anonymity of gamete donors in the context of medically-assisted reproduction techniques (ART) and the right of the offspring to know their genetic or biological parents' identity is a controversial and widely debated topic in the scientific literature. The positions on the issue in each country are different. Sometimes they are in opposition to each other even in countries with strong similarities, such as those in the European Union (EU), in the framework of shared ethical values. Although some countries still enshrine the rule of anonymity, there is an undeniable tendency to guarantee the right to know one's origins by creating relevant exceptions or abolishing donor anonymity status altogether. 16. This article offers ethical and legal considerations of whether the so-called 'right to be forgotten' (RTBF) could be extended to include gamete donors' right to remain anonymous. This perspective goes against the general trend, certainly in Europe, of recognizing that offspring born from donor gametes have a right to access information relating to their genetic progenitors. The novel addition is to question whether the General Data Protection Regulation (GDPR) might provide fertile ground for questioning this approach, and effectively support those jurisdictions where anonymity is still possible.


Resumen: 20. El anonimato de los donantes de gametos en el contexto de las técnicas de reproducción médicamente asistida (RM) y el derecho de la descendencia a conocer su identidad genética o biológica es un tema controvertido y ampliamente debatido en la literatura científica. Las posiciones sobre el tema en cada país son diferentes. A veces se oponen entre sí, incluso en países con fuertes similitudes, como los de la Unión Europea (UE), en el marco de valores éticos compartidos. Aunque algunos países siguen consagrando la norma del anonimato, es innegable la tendencia a garantizar el derecho a conocer el propio origen creando las excepciones pertinentes o suprimiendo por completo el estatus de anonimato del donante. 21. Este artículo ofrece consideraciones éticas y jurídicas sobre si el llamado "derecho al olvido" podría ampliarse para incluir el derecho de los donantes de gametos a permanecer en el anonimato. Esta opinión es contraria a la tendencia general, ciertamente en Europa, de reconocer que los hijos nacidos de gametos donados tienen derecho a acceder a la información relativa a sus padres genéticos. La nueva adición consiste en debatir si el Reglamento general de protección de datos (RGPD) podría proporcionar un terreno fértil para cuestionar este enfoque y apoyar efectivamente a las jurisdicciones en las que el anonimato sigue siendo posible.


Resumo 25. O anonimato dos dadores de gâmetas no contexto das técnicas de reprodução medicamente assistida (RMA) e o direito da descendência a conhecer a sua identidade genética ou biológica é um tema controverso e amplamente debatido na literatura científica. As posições sobre a questão em cada país são diferentes. Por vezes estão em oposição umas às outras, mesmo em países com fortes semelhanças, como os da União Europeia (UE), no quadro de valores éticos partilhados. Embora alguns países ainda consagrem a regra do anonimato, existe uma tendência inegável para garantir o direito de conhecer as suas origens, criando exceções relevantes ou abolindo completamente o estatuto de anonimato dos dadores. 26. Este artigo oferece considerações éticas e legais sobre se o chamado "direito ao esquecimento" poderia ser alargado para incluir o direito dos dadores de gâmetas a permanecerem anónimos. Esta perspetiva vai contra a tendência geral, certamente na Europa, de reconhecer que os descendentes nascidos de gâmetas doadas têm o direito de aceder à informação relacionada com os seus progenitores genéticos. O novo aditamento é debater se o Regulamento Geral de Proteção de Dados (RGPD) poderá fornecer um terreno fértil para questionar esta abordagem, e apoiar efetivamente as jurisdições onde o anonimato ainda é possível.


Sujets)
Humains , Confidentialité/éthique , Droits des patients , Don dirigé de tissus/éthique , Donneurs de tissus , Confidentialité/législation et jurisprudence , Vie privée , Divulgation/législation et jurisprudence , Divulgation/éthique , Don dirigé de tissus/législation et jurisprudence , Cellules germinales
14.
Rev. biol. trop ; 69(supl. 1)mar. 2021.
Article Dans Anglais | LILACS, SaludCR | ID: biblio-1507765

Résumé

Introduction: Photoperiod is, together with temperature and food availability, one of the main stimuli in the regulation of gametogenesis in a wide variety of species. Objective: To evaluate the effect of photoperiod on the production of mature gametes in cultured Arbacia dufresnii. Methods: An experiment was carried out with three varying light-dark regimes/treatments: constant light (24 h light), neutral photoperiod (12 h light, 12 h darkness), and constant darkness (24 h darkness). Twenty females were used in each treatment. All were induced to spawn and, ten randomly selected females from each treatment were induced to spawn again after 30 days. After 60 days, spawning was induced in the remaining females. The gametes were collected in filtered seawater, fixed in Davidson solution, quantified and measured per individual in triplicate in a Sedgewick-Rafter chamber. To determine maturation, fertilization success was evaluated 30 minutes after fertilization. Results: Our results showed that in the aquaculture system, after only two months, mature gametes were obtained, and in the neutral light regime there were 10 times more gametes than the number produced in wild sea urchins during the spawning period in question. We also found that with a greater exposure to light, a lower number of mature gametes was produced. Conclusions: This study suggests the viability of the production of mature gametes in a short period of time as regards Arbacia dufresnii.


Introducción: El fotoperiodo es, junto con la temperatura y la disponibilidad de alimentos, uno de los principales estímulos para el desarrollo de la gametogénesis en una amplia variedad de especies. Objetivo: Evaluar el efecto del fotoperiodo en la producción de gametas maduras de Arbacia dufresnii en un sistema de recirculación cerrado para determinar el mejor fotoperiodo para una acuicultura novedosa, enfocada en la producción de gametas con alta concentración de pigmentos para usos biotecnológicos. Métodos: Se realizó un experimento con tres regímenes/tratamientos diferentes de luz y oscuridad: luz constante (luz durante 24 h), fotoperiodo neutro (12 h de luz, 12 h de oscuridad) y oscuridad constante (oscuridad durante 24 h). Se utilizaron veinte hembras en cada tratamiento. Se indujo a todas las hembras a desovar al comienzo del experimento. Después de 30 días, diez hembras seleccionadas al azar de cada tratamiento fueron inducidas a desovar nuevamente. Al final del experimento, después de 60 días, se indujo el desove a las hembras restantes en cada tratamiento. Las gametas se recolectaron en agua de mar filtrada, se fijaron en solución de Davidson, se cuantificaron y midieron por triplicado en una cámara Sedgewick-Rafter. Para determinar la maduración, se evaluó el éxito de la fecundación después de 30 minutos de fertilización, calculando el porcentaje de huevos fertilizados. Resultados: Nuestros resultados muestran que, en el sistema acuícola, en solo dos meses se obtuvieron gametas maduras y casi 10 veces más la cantidad producida por los erizos de mar en su ambiente natural usando el fotoperiodo neutro (12 h luz:12 h oscuridad). También encontramos que la mayor exposición a la luz produce la menor cantidad de gametas maduras. Conclusión: Este estudio sugiere la viabilidad de la producción de gametos maduros en un corto período de tiempo en Arbacia dufresnii.


Sujets)
Animaux , Echinoidea/croissance et développement , Arbacia/anatomie et histologie , Cellules germinales , Organismes aquatiques , Gonades/anatomie et histologie , Mexique
15.
Biosci. j. (Online) ; 37: e37035, Jan.-Dec. 2021. graf, tab
Article Dans Anglais | LILACS | ID: biblio-1359546

Résumé

Many studies have been trying to establish standard protocols for animal experimentation, especially for animal species or strains, to master research variables with high precision. The main mouse strains used in the field of the biology of reproduction are Swiss, Balb/c, and C57BL/6. Since some of the strains show reproduction limitations, such as the size of the litter, the present study aimed to compare their spermatogenic processes to verify differences regarding the testicular parenchyma and germ cell populations, which could explain low offspring production. In addition, the present study provides additional information concerning the testicular parenchyma of such strains, which consequently would help researchers to choose the most suitable strain for reproductive studies. Six adult male mice were used for each of the strains. After euthanasia, the testes were weighed, fixated with Karnovsky fixative, embedded in methacrylate, sectioned, and stained with toluidine blue/sodium borate 1%. Morphometrical analyses from the testicular parenchyma (seminiferous tubules and interstitium) were made using the software ImageJ. Germ and Sertoli cells populations were counted in seminiferous tubules cross-sections at stage I of the seminiferous epithelium cycle. The lowest body and testicular weights were observed in C57BL/6 animals, followed by Balb/c and Swiss, however, the relative testes, parenchyma, and albuginea weights were significantly lower only in C57BL/6. Despite the seminiferous tubules and seminiferous epithelium proportions were lower in Swiss animals, their relative amount related to the body weight was the same among strains. The total number of germ cells was higher in Swiss animals, reflecting higher spermatogenic yield and daily sperm production. Due to the lower relative number of Sertoli cells, the Swiss animals showed the highest Sertoli cell index and support capacity. On the other hand, the lowest pathological indexes regarding the germ cells were observed in Balb/c animals, followed by Swiss and C57BL/6. In the interstitium, the proportion of blood vessels was lower in Swiss mice, while the lymphatic cell proportion was lower in C57BL/6 animals. Moreover, the highest proportions of Leydig cells and macrophages were noticed in Swiss mice, which may indicate increased testosterone levels. Altogether, such observations must be taken into account when choosing any of the studied strains for reproduction studies.


Sujets)
Rats , Spermatogenèse , Cellules germinales
16.
Article Dans Chinois | WPRIM | ID: wpr-879573

Résumé

The development of female germ cells can be mainly divided into two stages: fetal germ cells and oocytes in folliculogenesis after puberty. Mitosis-meiosis transition, meiosis arrest and re-activation are the key phases of the development. Several phases may be characterized by their distinct molecular events, which involve precise regulation of gene expression and interaction with corresponding gonadal niche cells. In recent years, single-cell transcriptome studies have clarified phase-specific patterns of gene expression, signaling pathways and epigenetic modification during oogenesis and folliculogenesis. These works have provided important insights into the development of female germ cells and pathogenesis of germ-cell related diseases, which may promote clinical application of reproductive genetic research.


Sujets)
Femelle , Humains , Cellules germinales , Méiose , Ovocytes , Ovogenèse/génétique , Transduction du signal
17.
Article Dans Chinois | WPRIM | ID: wpr-922005

Résumé

OBJECTIVE@#To report on a family which has two siblings with SCN2A mutation caused by germline mosaicism suffering from autism spectrum disorder/development delay (ASD/DD).@*METHODS@#Clinical data was collected for the proband and his parents. Next generation sequencing (NGS) was carried out on the proband and his parents. Suspected mutations were verified by Sanger sequencing of the proband, his parents and brother. To detect whether there is a low proportion of somatic mosaicism in the parents, a droplet digital PCR was conducted. The result of ddPCR showed that the father was germline mosaicism (0.233%).@*RESULTS@#NGS has identified a de novo splicing mutation of the SCN2A gene, c.605+1G>A, in the proband and his brother. Combined with its clinical phenotype and inheritance pattern, SCN2A was judged to be the pathogenic gene. Above findings strongly suggested parental germline mosaicism.@*CONCLUSION@#ASD/DD in siblings with SCN2A mutations caused by germline mosaicism. Paternal mosaicism should be considered as one of the important inheritance patterns for counseling parents with a child carrying SCN2A mutation. The ddPCR can help to reveal very low proportion of germline mosaicism.


Sujets)
Humains , Mâle , Trouble du spectre autistique , Cellules germinales , Mosaïcisme , Mutation , /génétique , Fratrie
18.
Clinics ; 76: e2837, 2021. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1286084

Résumé

OBJECTIVES: In breast cancer (BC) patients, the frequency of germline BRCA mutations (gBRCA) may vary according to the ethnic background, age, and family history of cancer. Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) is the second most common somatic mutated gene in BC; however, the association of mutations in both genes with cancer has not been thoroughly investigated. Thus, our aims were to investigate gBRCA mutation frequency in a cohort of postmenopausal Brazilian BC patients and the association of gBRCA1/BRCA2 and PIK3CA somatic mutations. METHODS: Forty-nine postmenopausal (>55 years) and forty-one young (≤35 years) BC patients were included in this study. The postmenopausal group included patients who reported a positive family history of cancer. For these patients, gBRCA1/BRCA2 were sequenced using next-generation sequencing (NGS) or Sanger sequencing. Data for gBRCA in young patients were already available from a previous study. DNA from formalin-fixed, paraffin-embedded (FFPE) tumors was obtained from 27 postmenopausal and 41 young patients for analyzing exons 9 and 20 of PIK3CA. The association between gBRCA1/BRCA2 and somatic mutations in PIK3CA was investigated. RESULTS: The overall frequency of gBRCA1/BRCA2 among the 49 postmenopausal patients was 10.2%. The frequencies of somatic mutations in PIK3CA in the postmenopausal and young patients were 37% and 17%, respectively (ns). The most common PIK3CA mutation was found to be E454A. Nonsense and frameshift mutations, which may counteract the oncogenic potential of PIK3CA were also detected. Regardless of age, 25% of BRCA1/BRCA2 mutation carriers and non-carriers , each, had PIK3CA somatic mutations. CONCLUSIONS: Data obtained indicate that BRCA1/BRCA2 gene testing may be considered for postmenopausal patients with BC who have a family history of cancer. Although some of them are not considered pathogenic, somatic variants of PIK3CA are frequently observed in BC patients, especially in postmenopausal patients.


Sujets)
Humains , Femelle , Adulte , Adulte d'âge moyen , Tumeurs de l'ovaire , Tumeurs du sein/génétique , Brésil , Post-ménopause , Mutation germinale , Prédisposition génétique à une maladie/génétique , Cellules germinales , Mutation
19.
Int. j. morphol ; 38(6): 1525-1527, Dec. 2020. graf
Article Dans Anglais | LILACS | ID: biblio-1134471

Résumé

SUMMARY: The study reported the influence of the high and acute dose of Letrozole on the testis morphology in paca (Cuniculus paca), an aromatase inhibitor that reduces the endogenous estrogen, the essential hormone for spermatogenesis. Morphological changes were observed in seminiferous epithelium with germ cells with apoptotic characteristics and presence of vacuoles and nuclei in pycnose.


RESUMEN: El objetivo de este estudio fue analizar la influencia de una dosis alta de Letrozol en la morfología de los testículos de la paca (Cuniculus paca), un inhibidor de la aromatasa que reduce el estrógeno endógeno, la hormona esencial para la espermatogénesis. Se observaron cambios morfológicos en el epitelio seminífero con células germinales con características apoptóticas y la presencia de vacuolas y núcleos en picnosis.


Sujets)
Animaux , Mâle , Testicule/effets des médicaments et des substances chimiques , Inhibiteurs de l'aromatase/administration et posologie , Cuniculidae , Létrozole/administration et posologie , Épithélium séminifère/effets des médicaments et des substances chimiques , Spermatogenèse/effets des médicaments et des substances chimiques , Immunohistochimie , Orchidectomie , Microscopie électronique à transmission , Cellules germinales/effets des médicaments et des substances chimiques
20.
Cambios rev. méd ; 19(1): 74-79, 30/06/2020. ilus.
Article Dans Espagnol | LILACS | ID: biblio-1122653

Résumé

INTRODUCCIÓN. Los tumores de células germinales del ovario de carácter maligno son infrecuentes en la adolescencia. Los disgerminomas se caracterizan por crecimiento rápi-do, diseminación linfática, alta sensibilidad a la radioterapia y quimioterapia. OBJETIVO. Establecer la presentación clínica, métodos diagnósticos y tratamiento para el manejo del disgerminoma ovárico en una adolescente. CASO CLÍNICO. Paciente mestiza de 14 años que acudió por dolor abdominal y masa palpable en región abdominopélvica asociados a elevación de marcadores séricos tumorales. Los reportes de imagen informaron masa ane-xial derecha, sólida de bordes lobulados y bien definidos. RESULTADOS. Se realizó exére-sis del tumor con protocolo de ovario conservador. El postoperatorio describió tumor ovári-co de 20 cm, lobulado y sólido que comprometió el ovario derecho en toda su extensión. El estudio histopatológico reportó: disgerminoma en estadio patológico IA moderadamente diferenciado, con extensión tumoral a pared de la trompa uterina derecha. DISCUSIÓN. El caso coincidió con otros reportes descritos en la literatura, donde la presentación clínica fue similar y el abordaje terapéutico con un protocolo de ovario conservador más la quimio-terapia adyuvante fueron la elección más óptima para preservar la función endocrina y la fertilidad en la paciente. CONCLUSIÓN. Los exámenes complementarios para determinar el diagnóstico fueron los marcadores tumorales, la ecografía pélvica y la tomografía axial computarizada simple y contrastada de abdomen y pelvis. La cirugía conservadora abierta es gold standard complementada con quimioterapia adyuvante en la adolescente.


INTRODUCTION. Germ cells tumors of the ovary of a malignant nature are uncommon in the adolescence. Dysgerminomas are characterized by rapid growth, lymphatic disse-mination, high sensitivity to radiotherapy and chemotherapy. OBJECTIVE. Establish the clinical presentation and diagnostic methods of ovarian dysgerminoma in the pediatric age for a correct therapeutic approach. CLINICAL CASE. A mestiza female of 14 years old, who has abdominal pain and a palpable mass in the abdominal pelvic region, and also elevation of the serum tumor markers. Image reports showed right solid adnexal mass with well-defined lobed edges. RESULTS Tumor exeresis was performed with a conservative ovarian protocol. The postoperative findings described a 20 cm, lobulated, solid ovarian tumor that compromised the right ovary in its entirety. The histopathological study repor-ted: moderately differentiated pathological stage dysgerminoma IA, with tumor extension to the wall of the right uterine tube. DISCUSSION. The case agrees with other reports described in the literature where the clinical presentation was similar and the therapeutic approach with a conservative ovary protocol plus adjuvant chemotherapy were the most optimal choice to preserve endocrine function and fertility in the patient. CONCLUSION. The complementary exams to reach the diagnosis were tumor markers, pelvic ultrasound and simple and contrasted computarized axial tomography of the abdomen and pelvis. Open conservative surgery was the gold standard supplemented with adjuvant chemothe-rapy in adolescent.


Sujets)
Humains , Femelle , Adolescent , Tumeurs de l'ovaire , Ovaire , Adolescent , Traitement médicamenteux , Dysgerminome , Fécondité , Radiothérapie , Marqueurs biologiques tumoraux , Douleur abdominale , Trompes utérines , Cellules germinales , Tumeurs
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