This thesis describes a study of the aggregational behaviour of egg yolk lecithin (EYL), a natural lecithin, and bile salt mixtures especially with respect to an increase of the ionic strength of the solvent. Mixtures of two amphiphiles with very different spontaneous curvature as EYL lecithin and bile salt form mixed micelles and vesicles in aqueous solution. Their properties have been well-studied under physiological conditions, i.e. 150 mM electrolyte concentration and pH 7- 8, while other conditions are still hardly explored. Upon increasing ionic strength the formed structures and the transitional pathways (micelles, coexistence of micelles and vesicles, and vesicles) change the generated structures completely from those observed under physiological conditions. We quantitatively determined these structures formed in a broad range of electrolyte concentrations with various scattering techniques, x-ray, light and neutron scattering and calorimetry. With calorimetry, phase diagrams in the EYL and bile salt concentration phase plane were determined at various ionic strength ranging from physiological salt concentration to up to 1000 mM. Additionally a new electrochemical approach using functionalised electrodes, i.e. sensitive and selective to bile salt, and thus to control the bile salt concentration in solution (concentrations below the critical micellar concentration (cmc)) was attempted, since bile salt removal or injection drives the micelle-to-vesicle or the vesicle-to-micelle transition, respectively, of the mixed aggregational system of EYL/bile salt. Although this control was not achieved within the framework of this thesis, promising results show directions for future experiments.

No description available.

The effect of several fundamental reproductive 'decisions' upon reproductive success were examined over a three year period at a large, inland gullery in the Pennines. Variations in reproductive parameters in relation to timing of breeding and reproductive success were compared among years. Determinants of the degree of hatching asynchrony were identified. Eggs from two years were taken for yolk lipid analysis, using gas chromatography. Variation in micronutrient content of eggs within clutches and between years was assessed in relation to egg size and yolk size, in order to examine resource allocation decisions of individuals. Timing of breeding of individuals was experimentally manipulated through the exchange of whole clutches of eggs between early and late laying birds, whilst controlling for variation in clutch size and egg-size, in order to assess whether the seasonal decrease in reproductive success was best explained by a decrease in food supply or differences in quality among parents. I experimentally manipulated the within-brood mass hierarchy of gulls, whilst controlling for variation in both chick quality and parental quality, in order to assess the effect of hatching asynchrony per se on chick growth and survival, and whether parents optimized the degree of hatching asynchrony with respect to the prevailing food supply. Brood size was experimentally reduced in order to assess the costs and benefits of the production of supernumary young. This was acheived by comparison of chick growth, feather development and chick survival of unmanipulated three-chick broods with broods where either the a-chick or the c- chick had been removed. I present a general discussion of the results within the context of life-history theory and a model for the evolution of hatching asynchrony in the lesser black-backed gull.

O saco vitelino é uma das membranas extra-embrionárias que desempenha um papel importante para a sobrevivência inicial do embrião, atua como fonte de nutrição durante o período em que a placenta verdadeira ainda não está completamente formada. É uma provável fonte de células tronco, o qual abriga as primeiras células do sangue durante o desenvolvimento em mamíferos, os eritrócitos, os quais expressam fatores de transcrição que especificam estas células a seu destino hematopoiético. O objetivo deste trabalho foi caracterizar as células tronco hematopoéticas provenientes do saco vitelino de embriões bovinos, em diferentes fases gestacionais, sendo estes coletados em abatedouro local. Para descrição da análise macroscópica e cultivo celular das células do saco vitelino, os embriões bovinos foram divididos em grupos de idade gestacional: Grupo I (25 a 29 dias), Grupo II (30 a 34 dias), Grupo III (35 a 39 dias), Grupo IV (40 a 44 dias) e Grupo V (45 a 50 dias) em que permaneceram mais tempo em cultura e apresentaram a formação de aglomerados celulares, diferente dos grupos IV e V (40 a 45 dias) em que permaneceram poucos dias em cultura e não apresentaram aglomerados celulares. Esta divergência relaciona-se à idade gestacional (45 a 50 dias), período em que se inicia a regressão do saco vitelino. Em citometria de fluxo os grupos I, II e III (25 a 39 dias) obtiveram características semelhantes, alta expressão de marcadores hematopoéticos (CD34, CD90 e CD117). Para os grupos IV e V (40 a 50 dias) observa-se um declínio da expressão de CD34 e CD117 (marcadores hematopoéticos) e no grupo V houve um acréscimo da expressão de CD45 (marcador para leucócito) confirmando que estas células não estão mantendo-se indiferenciadas As células demonstraram ser resistentes a criopreservação, capazes de formar colônias em matriz de Metilcelulose, mostraram a formação de colônias após 14 dias em cultivo e a morfologia para células sanguíneas (linfócitos e monócitos) foi confirmada na citologia celular. Na expressão gênica obteve-se baixa expressão do gene GATA3, níveis diferentes de expressão entre os grupos para o marcador RUNX1 e ANXA5. Dessa forma, nossos achados mais significativos comprovaram o isolamento de células hematopoéticas a partir do saco vitelino de embriões bovinos, sugerindo que este é uma fonte laboriosa, porém viável e eficaz para a obtenção de células tronco para futuras aplicações na terapia celular e gênica. / The yolk sac is one of the extra-embryonic membranes which plays an important role in early embryonic survival and serves as source of nutrition during the period where in the placenta is not completely true formed. The yolk sac is a likely source of stem cells, which have first blood cells during development in mammals, the red blood cells, which express transcription factors that specify these hematopoietic cells to their destination. This study aimed to identify and characterize hematopoietic stem cells from the yolk sac of bovine embryos at different stages of pregnancy, which are collected at a local slaughterhouse. For a description of the macroscopic and cellular culture of yolk sac cells, are as follows bovine embryos were divided into groups of gestational age: Group I (25 to 29 days), Group II (30 to 34 days), Group III (35 to 39 days ), Group IV (40 to 44 days) and Group V (45 to 50 days) which stayed longer in culture and showed the formation of cell clusters, different from groups IV and V (40-45 days) in few that remained days in culture and showed no cell clumps. This divergence is related to gestational age (45 to 50 days), during which begins regression of the yolk sac. In flow cytometry groups I, II and III (25 to 39 days) had similar characteristics, high expression of hematopoietic markers (CD34, CD90 and CD117). For the groups IV and V (40 to 50 days) it is observed a decrease in expression of CD117 and CD34 (hematopoietic markers) and in group V were increased expression of CD45 (leukocyte marker), confirming that these cells are not keeping Undifferentiated cells are shown to be resistant to cryopreservation, capable of forming colonies in methylcellulose matrix showed the formation of colonies after 14 days in culture morphology and to blood cells (lymphocytes and monocytes) was confirmed by cytology cell. In gene expression was low GATA3 gene expression, different levels of expression between the groups for the marker and RUNX1 ANXA5. Our most significant findings confirmed the isolation and identification of hematopoietic cells from the bovine embryo yolk sac, therefore, it is feasible and an effective way of obtaining stem cells for future applications in cell therapy and gene.

The leopard gecko (Eublepharis macularius) is a reptile species in which embryonic temperature contributes both to sex determination and within- sex polymorphisms. Its life history makes the leopard gecko a model system for seeking ontogenic and proximate explanations for within-sex variation in sexually dimorphic behavior and neurophysiology, necessary attributes for reproductive success. For my dissertation I have incorporated the role of androgens that potentially modulate incubation temperature effects on behavioral and brain variation, which I approached using embryo and adult leopard geckos. First, I found that that the bias of same-sex clutch siblings is primarily incubation temperature- dependent and any maternal or genetic effects on same-sex clutch siblings are secondary. Second, I found that testosterone concentrations in the yolk-albumen were higher in eggs of late development than early development at 26 °C, a female-producing incubation temperature, but did not differ from eggs incubated at another female-biased temperature. This increase in testosterone concentrations during the temperature sensitive period in putative females is a finding opposite of reported trends in most other reptiles studied to date. Further, I found that the embryonic environment influences male sociosexual investigation in the absence of gonadal hormones. Lastly, in adult males of 32.5 °C, a male-biased incubation temperature, I found that the phosphoprotein DARPP-32 that is activated by the D1 dopamine receptor in limbic brain regions is correlated to this sociosexual investigatory behavior. Neurons immunopositive for phosphorylated DARPP-32 were not only less dense in the nucleus accumbens of males who spent more time with other males, but also more dense in the preoptic area of males who spent more time with females. The use of phosphorylated DARPP-32 as marker for sociosexual exposure is novel in a lizard species. Taken together, in support of previous studies, these results show that differences in embryonic environment stem primarily from incubation temperature, can explain behavioral differences in adulthood in the absence of hormones, and, in concert with hormonal manipulation, can influence neuronal marker sensitivity to sociosexual exposure. / text

Vitelline membrane strength plays a role in preventing contamination of albumen by yolk during separation and is important to food safety. Two experiments were conducted to determine if a relationship exists between vitelline membrane protein banding patterns, interior egg quality, and vitelline membrane rupture strength. Eggs were gathered from commercial egg producers from pre-molt (26 wk or 72 wk) and post-molted (74 wk or 82 wk) hens. In each of two trials twenty-one eggs were gathered and stored (4°C) per experiment. Three eggs were evaluated on days 0, 7, 14, 21, 28, 35, and 42 for eggs from pre-molted hens; and 1, 7, 14, 21, 28, 35, and 42 for eggs from molted hens for changes in SDS-PAGE protein banding patterns. The yolk from each egg was isolated and rolled on a wet paper towel to remove adhering albumen. The yolk was emptied and washed. The whole membrane was placed into double deionized water and divided into two sections. The first section was the whole membrane sample and the other was separated by forceps into inner and outer membrane samples. The three sections were dissolved separately in 1% SDS/70 mM Tris/HCl, pH 6.8. Protein concentration was determined using the Lowry method and proteins separated on 4-20% gradient gel by SDS-PAGE. Protein banding patterns were analyzed using the Bio-Rad Multi-Analyst Densitometer. Reductions of VMO I and GP II occurred along with reductions in the protein bands between 60 to 100 kDa. In each of two trials, an additional one hundred forty eggs were gathered at the same time from the same flock and stored at 4°C. Twenty eggs were evaluated for quality on days 0, 7, 14, 21, 28, 35, and 42 for eggs from pre-molted hens; and 1, 7, 14, 21, 28, 35, and 42 for eggs from molted hens. Yolk index, albumen height, albumen pH, and yolk pH were determined. Vitelline membrane strength was determined using a compression anvil. Two different treatments were used on the yolk when evaluating rupture strength: 10 egg yolks with inner thin albumen layer, and 10 egg yolks rolled on wet paper towel to remove inner thin albumen layer. Interior egg quality and vitelline membrane strength declined during storage.

Pseudomonas Aeruginosa is a common gram-negative bacterium present in the environment. It causes severe infections in immunosuppressed patients. Cystic fibrosis patients are especially at risk of being infected with Pseudomonas Aeruginosa. Ongoing studies are preformed to find alternative therapies to antibiotics, due to increased resistance. One new treatment is intake of specific IgY antibodies against Pseudomonas Aeruginosa as an oral therapy. The problem today is that IgY solutions must be kept frozen until consumed.  In this study we examined the possibility to freeze-dry specific IgY antibodies without losing any activity or specificity of the antibodies. This would be more convenient of patients, as well as it makes transportation and storage easier.  The methods used were ELISA for control of activity, western blot analysis and SDS-PAGE gel for control of specificity. Three different batches of the IgY anti-Pseudomonas Aeruginosa solution were tested. The results showed that no loss in activity occurred that would affect clinical outcome or change of specificity in the antibodies after freeze-drying appears. This indicates that it is possible to replace the liquid antibody to a freeze-dried powder.

Diss. (sammanfattning) Uppsala : Univ., 2002. / Härtill 6 uppsatser.

Made available in DSpace on 2014-06-11T19:27:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-07-30Bitstream added on 2014-06-13T18:31:48Z : No. of bitstreams: 1 denadai_jc_me_botfmvz.pdf: 230894 bytes, checksum: bfcbfff893b67e63484c42c437614bda (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Estudos avícolas usando isótopos estáveis como traçadores em suas dietas fornecem estimativas de quão rapidamente os isótopos estáveis dos tecidos são substituídos por isótopos derivados da dieta. Estabeleceu-se taxas de turnover, meia-vida e substituição total do 13C no sangue, ovo (albúmen + gema), albúmen e gema de aves de postura, pela troca de dietas compostas de plantas dos ciclos fotossintéticos C3 e C4. E avaliou o efeito das dietas quanto ao fracionamento isotópico dieta-tecido e bromatologia do albúmen e da gema. O turnover é influenciado pela qualidade da dieta oferecida a ave. A comparação entre as meias-vidas do sangue, ovo, gema e albúmen, respectivamente, mostra que a dieta RC4 apresentou valores de meia-vida maiores que os outros tratamentos (RC4 = 13,3; 4,8; 5,5 e 5,2d; RC3 = 5,3; 3,8; 4,5 e 2,5d; RMC4 = 10,5; 3,8; 4,8 e 3,2d e RMC3 = 9,2; 3,5; 4,6 e 1,5d). Os tecidos estudados, pelo fato de apresentarem baixo fracionamento isotópico (?dieta-tecido = 0,1 l 0,5%), refletem bem a dieta consumida. Quanto a bromatologia da gema e albúmen não encontrou diferença significativa. / Poultry studies using stable isotopes as tracers in their diets supply information of how fast the stable isotopes from tissues are replaced by those diet-derivated. Established turnover rates, half-life and 13C total replacement in blood, egg (albumen + yolk), albumen and egg yolk from lay hens, through exchanging diets composed of C3 and C4 photosynthetic cycle plants. It also evaluated the effect of diets with regard to diet-tissue isotopic fractionation and bromatology of albumen and egg yolk. Turnover is influenced by quality of the diet used to feed the hens. The comparison among the half-lives of the blood, egg, yolk and albumen, respectively, shows that the diet RC4 presented half-life values higher than the other treatments (RC4 = 13,3; 4,8; 5,5 and 5,2days; RC3 = 5,3; 3,8; 4,5 and 2,5days; RMC4 = 10,5; 3,8; 4,8 and 3,2days and RMC3 = 9,2; 3,5; 4,6 and 1,5days). The studied tissues, due to the fact of presenting low isotopic fractionation (?diet-tissue = 0,1 l 0,5%), reflect well the diet intook. With relation to the albumen and yolk bromatology, none significant difference was found.

Made available in DSpace on 2014-06-11T19:29:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-11-03Bitstream added on 2014-06-13T19:38:33Z : No. of bitstreams: 1 felicio_gb_me_botfmvz.pdf: 193754 bytes, checksum: 08b79f22861822c2b5ed82d28f43112c (MD5) / Universidade Estadual Paulista (UNESP) / O objetivo do presente trabalho foi verificar a eficiência na congelabilidade e fertilidade da substituição da gema de ovo pela lecitina de soja no diluidor comercial Botu-Crio® (BC). Foram realizados dois experimentos laboratoriais e os respectivos testes de fertilidade. No experimento I comparou-se o diluente Botu-Crio® com o diluidor o Botu-Crio em que a gema de ovo foi substituída pela lecitina de soja numa concentração de 45g/L (BCLS45). Utilizou-se um ejaculado de 15 garanhões da raça Brasileiro de Hipismo (BH). Para o teste de fertilidade do Experimento I foi utilizado um garanhão da raça BH. Foram inseminados 12 éguas com o BC e 17 com o BCLS45. No experimento II comparou-se o diluente BC com o Botu-Crio sem gema de ovo (BCLS) acrescido de diferentes concentrações de lecitina de soja: 10,0; 12,5; 15,0; 17,5 e 20,0g/L (BCLS10; BCLS 12,5; BCLS15; BCLS17,5 e BCLS 20). Para tal, foram utilizados 1 ejaculado de 10 garanhões dde diferentes raças. Para o teste de fertilidade do experimento II utilizou-se um garanhão da raça Trakener e foram realizadas inseminações comparativas entre BC e BCLF20, sendo utilizadas 12 éguas com BC vs 10 éguas com BCLS20. Também comparou-se os diluente BC com o BCLS10, no qual foi utilizado um garanhão da raça Westfalen e foram inseminadas 8 éguas com BC vs 12 éguas com BCLS10. No Experimento I, os resultados de motilidade total, (61,4±16,2x61,4±15,9); motilidade progressiva, (27,0±9,8x26,7±10,6); íntegridade da membrana plasmática (IMP) (53,4±11,5x57,4±7,0); respectivamente para os diluidores Botu-Crio® e BCLS45, não havendo diferença entre os parâmetros espermáticos (p>0,05). No experimento II também não foram observadas diferenças entre os parâmetros avaliados, sendo para motilidade total BC (68,1±15,9) e BCLS10; BCLS12,5; BCLS15; BCLS17,5 e BCLS20 (65,8±13,5; 65,9±17,6; 67,6±11,2; 64,0±15,3 e 60,5±15,3)... / The objective of the present study was to verify the freezability and fertility of the BotuCrio without egg yolk extender where the egg yolk was replaced by soy been lecithin. Two experiments were performed on experiment 1 Botu-Crio® (BC) and Botu Crio without egg yolk containing 45g/L soy been lecithin (BCLS45) were compared. One ejaculated from 15 stallions from Braziliam Jump Horse Bred were used. On experiment 2, different concentrations of de soy bean lecithin: 10,0; 12,5; 15,0; 17,5 e 20,0g/L (BCLS10, BCLS12,5, BCLS17,5 e BCLS20) were compared. On the first fertility trial 12 mares were inseminated. With BC and 17 mares with Botu-Crio without egg yolk (BCLS45) using semen from only one stallion. On the second fertility trial 12 mares were inseminated with BC and another 10 mares with BCLS20. In another fertility trial 12 mares were inseminated with Botu-Crio vs and 8 mares with BCLS10 using frozen semen from a Westfalen stallion. No differences were observed on total motility (61.4 x 61.4); progressive motility, (27.0x26.7); plasmatic menbrane integrity (IMP) (53.4x57.4); between Botu-Crio® and Botu-Crio without egg yolk, (p>0,05). Also no differences were observed when different concentrations of soy been lecithin were used. The results were : For total motility BC (68,1±15,9) BCLS10, BCLS12,5, BCLS17,5 , BCLS20 (65,8±13,5; 65,9±17,6; 67,6±11,2; 64,0±15,3 ,60,5±15,3), for progressive motility: BC (28,8±9,2) and BCLS10, BCLS12,5, BCLS17,5 e BCLS20(29,8±9,8; 29,6±9,7; 31,4±8,2; 30,2±10,5 and 26,6±11,5) and IMP BC (50,7±10,3) and BCLS10, BCLS12,5, BCLS17,5 e BCLS20 (47,5±8,5; 46,6±12,2; 49,9±8,8; 46,1±10,3 and 43,6±10,9). The results of the fertility trials were: BC vs BCLS45 , 66,0 e 17% respectively (p<0,01); BC vs BCLS20 66,0 e 40,0% e BC vs BCLS10 75,0 e 41,0 respectively. In spite of similar laboratorial finds the fertility was different between... (Complete abstract click electronic access below)