337 resultados para Embryo yield


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Different cell cycle synchronization methods were used to increase the mitotic index and accuracy of sex determination in murine and bovine embryos. For sexing purposes, colchicine treatment for 2, 4, 6 and 8 h and the FdU-thymidine-colchicine combination were tested in murine embryos. The best results were obtained with colchicine treatment for 8 h (96.88% accuracy) and with FdU-thymidine-colchicine (97.22% accuracy). Mitotic indexes differed significantly between the 2 treatments (21.71% for colchicine and 32.95% for FdU-thymidine-colchicine). For sex identification of murine and bovine demi-embryos, both treatments were demonstrated to be equally effective (nearly 90%). The mitotic index for the FdU-treated murine demi-embryos (19.04%) was higher than the one obtained for the 8-h colchicine treatment (15.62%).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Pregnancy establishment, followed by birth of live offspring, is essential to all mammals. The biological processes leading up to pregnancy establishment, maintenance, and birth are complex and dependent on the coordinated timing of a series of events at the molecular, cellular, and physiological level. The ability to ovulate a competent oocyte, which is capable of undergoing fertilization, is only the initial step in achieving a successful pregnancy. Once fertilization has occurred and early embryonic development is initiated, early pregnancy detection is critical to provide proper prenatal care (humans) or appropriate management (domestic livestock). However, the simple presence of an embryo, early in gestation, does not guarantee the birth of a live offspring. Pregnancy loss (embryonic mortality, spontaneous abortions, etc.) has been well documented in all mammals, especially in humans and domestic livestock species, and is a major cause of reproductive loss. It has been estimated that only about 25-30 % of all fertilized oocytes in humans result in birth of a live offspring; however, identifying the embryos that will not survive to parturition has not been an easy task. Therefore, investigators have focused the identification of products in maternal circulation that permit the detection of an embryo and assessment of its well-being. This review will focus on the advances in predicting embryonic presence and viability, in vivo.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In the early vertebrate embryo, cardiac progenitor/precursor cells (CPs) give rise to cardiac structures. Better understanding their biological character is critical to understand the heart development and to apply CPs for the clinical arena. However, our knowledge remains incomplete. With the use of single-cell expression profiling, we have now revealed rapid and dynamic changes in gene expression profiles of the embryonic CPs during the early phase after their segregation from the cardiac mesoderm. Progressively, the nascent mesodermal gene Mesp1 terminated, and Nkx2-5+/Tbx5+ population rapidly replaced the Tbx5low+ population as the expression of the cardiac genes Tbx5 and Nkx2-5 increased. At the Early Headfold stage, Tbx5-expressing CPs gradually showed a unique molecular signature with signs of cardiomyocyte differentiation. Lineage-tracing revealed a developmentally distinct characteristic of this population. They underwent progressive differentiation only towards the cardiomyocyte lineage corresponding to the first heart field rather than being maintained as a progenitor pool. More importantly, Tbx5 likely plays an important role in a transcriptional network to regulate the distinct character of the FHF via a positive feedback loop to activate the robust expression of Tbx5 in CPs. These data expands our knowledge on the behavior of CPs during the early phase of cardiac development, subsequently providing a platform for further study.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Crops close to small water bodies may exhibit changes in yield if the water mass causes significant changes in the microclimate of areas near the reservoir shoreline. The scientific literature describes this effect as occurring gradually, with higher intensity in the sites near the shoreline and decreasing intensity with distance from the reservoir. Experiments with two soybean cultivars were conducted during four crop seasons to evaluate soybean yield in relation to distance from the Itaipu reservoir and determine the effect of air temperature and water availability on soybean crop yield. Fifteen experimental sites were distributed in three transects perpendicular to the Itaipu reservoir, covering an area at approximately 10 km from the shoreline. The yield gradient between the site closest to the reservoir and the sites farther away in each transect did not show a consistent trend, but varied as a function of distance, crop season, and cultivar. This finding indicates that the Itaipu reservoir does not affect the yield of soybean plants grown within approximately 10 km from the shoreline. In addition, the variation in yield among the experimental sites was not attributed to thermal conditions because the temperature was similar within transects. However, the crop water availability was responsible for higher differences in yield among the neighboring experimental sites related to water stress caused by spatial variability in rainfall, especially during the soybean reproductive period in January and February.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

O objetivo deste trabalho foi relatar o potencial da técnica de MALDI-MS para caracterizar espécies de lipídios presentes em um único embrião equino e estudar algumas estruturas lipídicas detectadas por dissociação induzida por colisão (CID). No espectro de modo íon positivo, pudemos observar espécies, principalmente, protonadas e sodiadas de esfingomielinas (SM), fosfatidileolinas (PC) e triacilgliceróis (TAG). No modo negativo, observamos fosfatidiletanolaminas (PE) e fosfatidilinositos (PI). Espectros de íons de lípidos com maior intensidade foram utilizados para demonstrar o potencial da informação estrutural por MALDI-MS/MS. O espectro no modo positivo de m/z (massa sobre carga) 760,6 (atribuída como PC34:1) apresentou características de fragmentos PC de m/z 184,1 (denominada cabeça polar de colina), além de perda neutral (NL) de m/z 183 (fosforilcolina). Para o íon de m/z 766,6 (atribuída como PE38:5), observou-se a NL de 140, característica do PE. Para o íon de m/z 808,7 (38,5 atribuído como PC), além do fragmento m/z 184,1 na NL de 183, foi possível observar a perda de trimetilamina (íon de m/z 749,6) e o ciclofosfano (íon de m/z 147,0). Finalmente, para o modo de íon negativo, foram isolados e fragmentados o íon de m/z 863,6 que foi atribuído como PI36:1, devido à presença de m/z 153 (fosfato de glicerol – H2O-H ), 223 (inositol fosfo - 2H2O-H) , 241 (fosfoinositol – H2O-H), 281 (ácido oleico) e 581,3 (lisofosfoinositol – H2O+H). Concluímos que a MALDI - MS permite a detecção de uma ampla gama de espécies de PC, SM, PE, PI e TAG lipídicas, bem como a caracterização rápida e confiante de estruturas lipídicas a partir de um único embrião equino.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The objective of this study was to investigate the influence of lineage of oocytes donors on the number and quality of oocytes obtained through ultrasound-guided follicular aspiration in Nellore breed cows derived from two lineages of bulls (Karvadi; K and Taj-Mahal; T). Both maternal (Km and Tm) and paternal (Kp and Tp) lineages, as well as their combinations were investigated. Oocyte aspirations were repeatedly performed with an aspiration interval of 15 days in 56 donor females. Recovered cumulus oocyte-complexes (COCs) were counted, morphologically examined and classified into seven categories (grades from I to VII) according to the number of layers of the cumulus oocyte and cytoplasm appearance. The mean number of oocytes retrieved from donors of lineage Tp-Tm was significantly higher (28.23±1.92, P<0.05) than those obtained from lineages Kp-Tm, Kp-Km, and Tp-Km (21.34±1.32, 21.28±1.73, and 16.72±1.31, respectively). There was no significant difference in the mean number of recovered oocytes between donors of lineages Kp-Km and Kp-Tm, whereas animals of lineage Tp-Km yielded the lowest number of oocytes. Higher mean number of grade III oocytes was recovered from donors of lineage Kp than lineage Tp (10.11±0.66 versus 8.79±0.58, respectively), with more grade III oocytes being obtained in both lineages as compared to the others. Paternal lineage did not influence the quality of recovered oocytes in any other category, but both Kp and Tp yielded a great mean number of oocytes graded as I, II, and III (3.14±0.21; 4.93±0.33, and 10.11±0.66 versus 3.19±0.21, 5.59±0.44, and 8.79±0.58, respectively) than those classified as IV, V, VI, and VII. However, when considering the data from the maternal lineage significantly more oocytes (P<0.05) of grade I, II and III were obtained from Taj-Mahal (11.67 ± 0.67, 5.9±0.42 and 3.64±0.25, respectively) than for lineage Karvadi, with similar results for oocytes of grades IV, V, VI, and VII. Similarly to the paternal lineage, the number of oocytes of grade III was superior (P<0.05) when compared to other categories for both lineages. In conclusion, we demonstrate here a direct influence of lineage of oocyte donor on the production and quality of oocytes obtained through ultrasound-guided follicular aspiration in Nellore cows.