How cell movements are coordinated during morphogenesis is not well understood. We focus on epiboly, which describes the thinning and spreading of a multilayered cell sheet. The first phase of epiboly involves the doming of the yolk cell up into the overlying blastoderm. We previously showed that over-expression of a dominant– negative eomesodermin a construct inhibits doming. Here I report my analysis of embryos lacking both maternal and zygotic Eomesodermin A (MZeomesa). eomesafh105 mutant embryos (1) exhibit a doming delay, (2) have defective yolk cell microtubules, (3) have tightly packed deep cells with more bleb – like protrusions and (4) express early endoderm markers abnormally. Despite these phenotypes, the majority of MZeomesa embryos are able to complete epiboly and form endodermal derivatives. In both Xenopus and mice, Eomesodermin has also been implicated in the regulation of gastrulation movements and cell fate specification, suggesting a conserved role for Eomesodermin throughout vertebrate development.

How cell movements are coordinated during morphogenesis is not well understood. We focus on epiboly, which describes the thinning and spreading of a multilayered cell sheet. The first phase of epiboly involves the doming of the yolk cell up into the overlying blastoderm. We previously showed that over-expression of a dominant– negative eomesodermin a construct inhibits doming. Here I report my analysis of embryos lacking both maternal and zygotic Eomesodermin A (MZeomesa). eomesafh105 mutant embryos (1) exhibit a doming delay, (2) have defective yolk cell microtubules, (3) have tightly packed deep cells with more bleb – like protrusions and (4) express early endoderm markers abnormally. Despite these phenotypes, the majority of MZeomesa embryos are able to complete epiboly and form endodermal derivatives. In both Xenopus and mice, Eomesodermin has also been implicated in the regulation of gastrulation movements and cell fate specification, suggesting a conserved role for Eomesodermin throughout vertebrate development.

In teleosts, the Yolk Syncytial Layer (YSL) is functionally similar to the anterior visceral endoderm found in mice and is required for morphogenesis of the overlying blastoderm. The YSL undergoes dramatic reorganization during early development through processes that mirror the morphogenetic movements of the blastoderm. The YSL and YSL nuclei (YSN) undergo epiboly, and during convergence and extension movements of the blastoderm, the YSN underneath the animal cap also converge and extend underneath the axial hypoblast. Our work with pollywog ( pwg ) maternal-effect mutants highlights the delicate control of the YSL during yolk morphogenesis, and provides novel insight into understanding which tissues of the embryo are affected by loss of a cohesive YSL. I found that pollywog encodes the zebrafish mitogen activated protein kinase kinase kinase 4 ( map3k4 ) gene and that it acts upstream of p38a MAPK in the YSL. I show that this pathway acts in the YSL along with a mixer gene family member, mix-type homeobox gene 1 ( mxtx1 ), to non-autonomously coordinate extracellular matrix deposition and morphogenetic movements in the overlying blastoderm. Our data describes an early and novel role for Map3k4, p38a and Mxtxl activity that is required for proper morphogenesis of the YSL and the blastoderm. In embryos lacking maternal Map3k4, the YSL undergoes a rapid and catastrophic retraction and the YSN lose their normal distribution around the yolk. The prechordal plate of pwg mutant embryos deflect laterally or plunge into the yolk, and the overall animalward extension of the prechordal plate is diminished. I also show that the anterior neural plate of pwg mutant embryos fail to converge dorsally to the same extent as in wild embryos. These data show that the p38 MAPK pathway is essential for maintaining normal yolk cell equilibrium during early development and that without proper cues from the YSL, the blastoderm cannot complete its morphogenetic movements. Incuded in this thesis is work highlighting the alpha-actinin gene family in zebrafish. alpha-actinins are actin microfilament crosslinking proteins. Vertebrate actinins fall into two classes: the broadly-expressed actinins 1 and 4 ( actn1 and actn4 ) and muscle-specific actinins, actn2 and actn3 . Members of this family have numerous roles, including regulation of cell adhesion, cell differentiation, directed cell motility, intracellular signaling and stabilization of f-actin at the sarcomeric Z-line in muscle. Here I identify five zebrafish actinin genes including two paralogs of ACTN3 . I describe the temporal and spatial expression patterns of these genes through embryonic development. All zebrafish actinin genes have unique expression profiles, indicating specialization of each gene. In particular the muscle actinins display preferential expression in different domains of axial, pharyngeal and cranial musculature. There is no identified avian actn3 and approximately 16% of humans are null for ACTN3 . Duplication of actn3 in the zebrafish indicates that variation in actn3 expression may promote physiological diversity in muscle function among vertebrates.

In an effort to determine the optimal temperature for rearing Centropomus undecimalis larvae during the yolk resorption period, larval development was measured under four different temperature regimes (23, 25, 28 and 31 °C). The eggs were incubated at 28 °C until hatching, which occurred at about 17 hours post-fertilization. After hatching, temperatures were adjusted to the respective treatment levels. Measurements were collected from 25 individual larvae across rearing temperatures at the following pre-determined time intervals: at hatching, 24 hours post hatch (hph), 48 hph, and 72 hph. Morphometric measurements were obtained from photomicrographs, including yolk sac length and height, oil globule diameter, standard length, body height at anal pore, and eye diameter. Larvae in the 25 °C treatment had longer median standard length, body height, and more energy reserves than those larvae reared at other temperatures. The yolk sac and oil-globule were present up to 72 hph at 23 and 25°C, while these were entirely consumed after 48 hph in treatments at 28 and 31 °C. Centropomus undecimalis larvae had the highest growth rates during the first 24 hph, and this period corresponded to the highest energy consumption as determined by the decrease in yolk-sac and oil-globule volume. Survival was assessed during the third trial only. The 31 °C treatment presented the worst survival percentages, with a maximum survival of 37.2% at 24 hph, and 100% mortality at 72 hph. The 25 °C treatment featured higher survival at the end of the trial than the other treatments with 1.7% survival. Eye diameter didn't vary significantly with time and was not a useful parameter for tracking development during yolk resorption. These results led to the conclusion that 25 °C was the optimal temperature to raise snook larvae during the yolk-resorption period.

No description available.

Made available in DSpace on 2016-08-15T20:31:06Z (GMT). No. of bitstreams: 1 AndreMV_DISSERT.pdf: 26149415 bytes, checksum: 8052cd9f22e05a0bada5a1c6b968c995 (MD5) Previous issue date: 2011-10-12 / The inversion period of the yolk sac as the dynamic which results from this process was studied in 30 female of prea on days 6, 10, 11 to 15, 20, 25, and 30 of gestation. Six groups of animals (one male for five females) were formed and kept in boxes of 5m2. Vaginal cytology was performed daily for detection of copulation. Pregnant females were separated of the other individuals of the group. They were euthanized using a specific anesthetic protocol for collection of the gestational sacs. Then, the material was processed for histology, immunohistochemistry, scanning electron microscopy, and transmission electron microscopy. At days 11 to 13 of gestation was observed the development of the parietal and visceral endoderm delimiting the yolk sac cavity. The parietal endoderm was coating the surface of the fetal side of the chorioallantoic placenta and surrounding the space bounded by the capsular decidua. These endoderm layers showed a prismatic shape and were separated of the trophoblast by a developed Reichert s membrane. The visceral endoderm contained vitelline vessels and villi in some areas. On the 13th day it was possible to establish as a basic condition before the inversion of teh yolk sac, the permanence of at least one of the three elements that characterized the bilaminar omphalopleure. On the 14th day of gestation the complete inversion of the yolk sac, which was characterized by the degeneration of both parietal endoderm and mural trophoblast, coupled with the gradual disappearance of the Reichert s membrane was observed. As a consequence of this, the visceral endoderm constitutes the interface with the uterine epithelium. After the inversion of the yolk sac, the parietal endoderm remained intact was the one which rested on the surface of the chorioallantoic placenta, which showed high columnar cells, characteristic of the pseudostratified epithelium. The visceral endoderm showed numerous apical villi mainly in regions close to the chorioallantoic placenta. The intense vascularization was confirmed by the immunohistochemistry reaction for vimentin associated with the scanning electron microscopy. During the continuous development of the embryo and chorioallantoic placenta it was also observed the development of an important area of apposition of both visceral and parietal endoderm whose proliferative capacity of these cells was demonstrated by immunohistochemistry using PCNA antibody. Therefore, we concluded the inversion of the yolk sac represents an anatomical arrangement in favor of embryonic development as well as an evolutionary characteristic in this rodent specie. / O período de inversão do saco vitelino bem como a dinâmica resultante deste processo foi estudado em 30 fêmeas de preás nos dias 6, 10, 11 a 15, 20, 25 e 30 de gestação. Foram formados seis grupos de animais numa relação de um macho para cinco fêmeas, mantidos em boxes de 5m2. Após formação dos grupos, diariamente eram realizados exames de citologia vaginal, para verificação de cópula, separando-se dos grupos as fêmeas que eram cobertas. A partir da ocorrência da cópula programaram-se as coletas dos sacos gestacionais mediante sacrifício das fêmeas gestantes através de protocolo anestésico específico. O material, então, era processado segundo técnicas para histologia convencional, imunohistoquímica, microscopia eletrônica de varredura e de transmissão. Nos dias de 11 a 13 de gestação observou-se o desenvolvimento dos endodermas parietal e visceral delimitando a cavidade do saco vitelino. O endoderma parietal foi evidenciado revestindo a superfície fetal da placenta corioalantoide bem como contornando o espaço delimitado pela decídua capsular. Estes endodermas apresentaram formato prismático e encontraram-se separados do trofoblasto por uma desenvolvida membrana de Reichert. Já o endoderma visceral continha vasos vitelínicos e possuía vilosidades apenas em determinadas áreas. No décimo terceiro dia, foi possível estabelecer como condição primordial antes da inversão, a permanência de pelo menos um dentre os três elementos que caracterizavam a onfalopleura bilaminar. No décimo quarto dia de gestação verificou-se a inversão do saco vitelino, caracterizada pela degeneração do endoderma parietal e trofoblasto mural, associado ao desaparecimento gradual da membrana de Reichert. Como consequência deste fenômeno, o endoderma visceral passou a constituir interface com o epitélio uterino. Após a inversão, o endoderma parietal que permaneceu íntegro foi aquele que se apoiava na superfície da placenta principal, apresentando células em formato colunar alto e característica de epitélio pseudoestratificado. O endoderma visceral apresentou numerosas vilosidades apicais principalmente em regiões próximas a placenta principal. A intensa vascularização desse endoderma foi evidenciada pela reação imunohistoquímica para vimentina e microscopia eletrônica de varredura. Com o contínuo desenvolvimento do embrião e placenta principal, observou-se o surgimento de importante área de aposição entre os endodermas visceral e parietal cuja capacidade proliferativa destas células foi demonstrada pela reação imunohistoquímica para o PCNA. Por conseguinte, concluiu-se que a inversão do saco vitelino representou uma disposição anatômica favorável ao desenvolvimento embrionário além de uma característica evolutiva nesta espécie de roedor.

The egg yolk chicken and pork lard as compared with other foods, have high cholesterol. 20 ml of gem shows on average 200 mg cholesterol and 20 ml of lard average value of 14 mg of cholesterol. Good food for experiences concerning cholesterol, are low cost compared them with cholesterol powder. Method: We used rabbits of New Zealand (n = 42) adults from 7 to 8 months of age divided into groups of 4: control group diet with 200 g and water ad libitum (G1), the group treated with 1 g of cholesterol (G2); group treated with 20 ml egg yolk (G3); group treated with 20 ml of lard (G4); group (G5) treated with 40 ml of yolk and the group (G6) treated with 40 ml of lard. All groups were fed during the period of 100 days with the aim of verifying which of the diet is best for induction of atherosclerosis. The blood collection for the dosages of the lipid profile of animals occurred at times 0, 30, 60 and 100 days. At the end of the trial period, the animals were subjected to euthanasia. Segments of the aortic arch, the right carotid artery and right femoral artery were collected for analysis histological. Results: As expected the group G1 not noticed amendment, the group G2 training light of atherosclerosis, the group returned G3 significant increase (p <0,05) in total cholesterol levels, the group G4 were not identified histological changes and G5 and G6 is not adapted the diet administered. By microscopic examination, were observed foam cells in the aortic arch, and femoral and carotid thickening of endothelium in the group G3 so significant comparing them with the G2. Conclusion: The diet enriched with egg yolk, chicken is the best option for formation of foam cells and thickening of endothelium, is practical and low cost for research on cholesterol and atherosclerosis. / A gema de ovo de galinha e a banha do porco, em relação aos outros alimentos, têm alto índice de colesterol total. 20 ml de gema apresenta em média 200 mg de colesterol total e 20 ml de banha valor médio de 14 mg de colesterol total. São bons alimentos para experiências referentes à colesterolemia, são de baixo custo comparando-os com colesterol puro. Métodos: Foram utilizados coelhos da Nova Zelândia (n=42) adultos entre 7 a 8 meses de idade divididos em grupos de 4: grupo controle com ração 200 g e água ad libitum (G1); o grupo tratado com 1 g de colesterol (G2); grupo tratado com 20 ml gema de ovo (G3); grupo tratado com 20 ml de banha (G4); grupo (G5) tratado com 40 ml de gema e o grupo (G6) tratado com 40 ml de banha. Todos os grupos foram alimentados durante o período de 100 dias tendo como objetivo verificar qual das dietas é melhor para indução da aterosclerose. A coleta de sangue para as dosagens do perfil lipídico dos animais aconteceram nos momentos 0, 30, 60 e 100 dias. Ao término do período experimental, os animais foram submetidos à eutanásia. Segmentos do arco aórtico, da artéria carótida direita e artéria femoral direita foram coletados para análise histológica. Resultados: Como esperado o grupo G1 não observou alteração, o grupo G2 formação leve de aterosclerose, o grupo G3 obteve aumento significante (p<0,05) nos níveis de colesterol total, o grupo G4 não foram identificada alterações histológicas e o G5 e G6 não se adaptaram a dieta administrada. Ao exame microscópico, foram observadas células espumosas no arco aórtico, femoral e carótida e espessamento de endotélio no grupo G3 de forma significante comparando-os ao G2. Conclusão: A dieta enriquecida com gema de ovo de galinha é a melhor opção para formação de células espumosas e espessamento de endotélio, é prática e de baixo custo para pesquisas com colesterolemia e aterosclerose.

With the aim of evaluating the internal and external of eggs of quality quail stored under refrigeration and at room temperature, we used 440 eggs Japanese quail collected after laying. The eggs were distributed in a completely randomized design in factorial 2x11 (2 storage temperature x 11 storage periods) with 20 repetitions. Analyses were performed on eggs at 0, 3, 6, 9, 12, 15, 18, 21, 24, 27 and 30 days of storage. The variables analyzed were weight loss (%), specific gravity (g / ml), yolk index and albumen percentages (%) of yolk, albumen and shell, shell thickness (mm), yolk color, pH albumen and yolk and Haugh Unit. Statistical analysis was performed using the System Analysis Statistical and Genetic (SAEG) and means compared by Newman Keuls test at 5% probability. Observed effect was (P<0,05) linear weight loss of eggs (%), specific gravity (g / ml), yolk index, albumen index, albumen percentage, yolk percentage, pH and yolk Haugh unit, in both storage temperatures. However, the pH of the albumen had an effect (P<0,05) quadratic for eggs stored at both storage temperatures. To eggshell percentage, shell thickness and yolk color not found a significant effect (P>0,05) among treatments. We conclude that Japanese quail eggs can be stored for up to 18 days at room temperature and 30 days under refrigeration. / Fundação de Amparo a Pesquisa do Estado de Alagoas / Com o objetivo de avaliar a qualidade interna e externa de ovos de codornas armazenados sob refrigeração e à temperatura ambiente, utilizou-se 440 ovos de codornas japonesas coletados após a postura. Os ovos foram distribuídos em um delineamento inteiramente casualizado em esquema fatorial 2x11 (2 temperaturas de armazenamento x 11 períodos de armazenamento) com 20 repetições. As análises foram efetuadas nos ovos com 0, 3, 6, 9, 12, 15, 18, 21, 24, 27 e 30 dias de armazenamento. As variáveis analisadas foram: perda de peso (%), gravidade específica (g/ml), índice de gema e de albúmen, porcentagens (%) de gema, albúmen e casca, espessura de casca (mm), coloração da gema, pH do albúmen e da gema e a Unidade Haugh. As análises estatísticas foram realizadas, utilizando o Sistema para Análises Estatísticas e Genética (SAEG) e as médias comparadas pelo teste Newman Keuls a 5% de probabilidade. Observou-se efeito (P<0,05) linear para perda de peso dos ovos (%), gravidade especifica (g/ml), índice de gema, índice de albúmen, porcentagem de albúmen, pH da gema e unidade Haugh, em ambas as temperaturas de estocagem e porcentagem de gema para os ovos armazenados sob refrigeração. Contudo, o pH do albúmen apresentou efeito (P<0,05) quadrático para os ovos armazenados em ambas as temperaturas de estocagem e a porcentagem de gema para os ovos armazenados em temperatura ambiente. Para porcentagem de casca, espessura da casca e coloração da gema não se constatou efeito significativo (P>0,05) entre os tratamentos. Concluiu-se que ovos de codornas japonesas podem ser armazenados por até 18 dias em temperatura ambiente e 30 dias sob refrigeração.

Made available in DSpace on 2014-12-17T14:03:45Z (GMT). No. of bitstreams: 1 HerykaMMR.pdf: 634847 bytes, checksum: 5ab27ecd338e547873827cb18935a22d (MD5) Previous issue date: 2007-07-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Vitamin A deficiency is a serious public health problem in developing countries, and it causes death and blindness among children in the developing countries. The fortification of food could be an important source of vitamins to control deficiency. 60 Coturnix coturnix japonica quails were used in a randomized design with duration of seven weeks. The birds were assigned into five treatments with four repetitions. The objective was to evaluate the influence of the supplementation with different levels of retinyl palmitate (2,000 IU, 4,000 IU, 8,000IU and 16,000 IU) in quails under the levels of retinyl in egg yolks. The method used to dose retinyl in yolks of quail eggs was High Performance Liquid Chromatography and the enzymatic method to quantify the cholesterol concentration. The weight and production of eggs was significantly modified by the supplementation with retinyl in the birds. The results showed a gradual increase in the incorporation of retinyl in the egg yolk as a response to the supplementation, reaching values 384% higher than the control values. By the end of the supplementations a significant reduction in the concentrations of retinyl in the eggs yolk was observed. The most lasting supplementations were with 8,000 IU and 16,000 IU which lasted for three weeks. The cholesterol content in eggs was not significantly modified. The consumption of one egg enriched with 16000UI of retinol palmitate in the present study, by day, would probably reach 10 and 7,3% of the daily recommendations of this micronutrient for children of 1 to 3 years of age, and for 4 to 8 years, respectively. The nutritional value of eggs, related to the vitamin A, can be improved by supplementation of quails / A defici?ncia de vitamina A ? um s?rio problema de sa?de p?blica, e causa a morte e cegueira em crian?as nos pa?ses em desenvolvimento. A fortifica??o de alimentos como ovos, pode ser uma importante fonte de vitaminas para o controle da defici?ncia. Foram utilizadas 60 codornas Coturnix coturnix japonica em delineamento experimental inteiramente ao acaso, com dura??o de sete semanas. As aves foram distribu?das em cinco tratamentos com quatro repeti??es cada. O objetivo foi avaliar a influ?ncia de diferentes n?veis de retinol palmitato (2000UI, 4000UI, 8000UI e 16000UI) em codornas sobre os n?veis de retinol na gema dos ovos. O m?todo utilizado para dosar retinol na gema dos ovos de codornas foi a Cromatografia L?quida de Alta Efici?ncia (CLAE) e o m?todo enzim?tico para quantificar a concentra??o de colesterol. O peso e a produ??o de ovos foram significativamente alterados pela suplementa??o oral com retinol nas aves. Os resultados mostraram um aumento progressivo na incorpora??o de retinol na gema do ovo em resposta ? suplementa??o, atingindo valores 384% superiores aos valores de controle. Ao t?rmino das suplementa??es foi observada uma diminui??o significativa nas concentra??es de retinol na gema dos ovos, sendo as suplementa??es com 8000UI e 16000UI as mais duradouras e mesmo ap?s tr?s semanas continuaram com os n?veis de retinol elevados. O conte?do de colesterol nos ovos n?o foi significativamente alterado. O consumo de um ovo enriquecido com 16000 UI de retinol palmitato no presente estudo, por dia, provavelmente atenderia em torno de 10 e 7,3% das recomenda??es di?rias deste micronutriente para crian?as na faixa et?ria de 1 a 3 anos, e 4 a 8 anos, respectivamente. O valor nutricional dos ovos, relacionado ? vitamina A, pode ser aumentado pela suplementa??o das codornas

Atualmente a terapia com células-tronco têm sido uma ferramenta útil na medicina regenerativa com alto potencial terapêutico devido à capacidade de auto renovação e diferenciação destas células. Nos últimos anos a ortopedia vem procurando novos métodos para um tratamento que obtenha como efeito a reparação de defeitos articulares de forma mais efetiva e sem procedimentos invasivos. Por isso, muitos estudos envolvendo terapia celular com objetivo de melhorar a reparação articular estão sendo realizados. O objetivo deste estudo foi avaliar a terapia com células-tronco de saco vitelino e de polpa dentária canina em cães com displasia coxofemoral mediante três aplicações celulares (dia 0, 30 e 60, e um controle dia 90). Para a avaliação dos animais tratados foi instituído um grupo controle para cada tipo celular testado, sendo avaliado o escore de claudicação, escore de atrofia muscular, questionário de qualidade de vida, avaliação radiográfica, análise do líquido sinovial e hemograma. Os resultados obtidos demonstraram não haver uma diferença estatística significante quando comparado os animais dos grupos tratamentos e controle. Quando comparado os animais dos grupos tratamento houve uma diferença estatística significante para os animais tratados com células-tronco de saco vitelino em relação aos animais tratados com células-tronco de polpa dentária. O tratamento com células de saco vitelino mostrou melhores resultados nos testes de Ortolani. / Currently, stem cell therapy have been a useful tool in regenerative medicine with high therapeutic potential due to the capacity for self renewal and differentiation of these cells. In recent years, orthopedics has been seeking new methods of treatment to obtain the effect of repair of articular defects more effectively and without invasive procedures. Therefore, many studies involving cell therapy in order to improve the repair articular are being conducted. The aim of this study was to evaluate the therapy with stem cells from the yolk sac and canine dental pulp in dogs with hip dysplasia by three mobile applications (day 0, 30 and 60, and one day control 90). For the evaluation of the treated animals was set up a control group for each cell type tested, and rated the lameness score, muscular atrophy score, a questionnaire about quality of life, radiographic evaluation, synovial fluidanalysis and blood count. The results showed that there was no statistically significant difference when compared animal treatment and control groups. Comparing the animals, treatment groups showed a statistically significant difference for the animals treated with stem cells from the yolk sac for the animals treated with stem cells from dental pulp. Treatment with yolk sac cells showed better results in Ortolani tests.