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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Textural and Physical Properties of Fat-Free Turkey-Beef Frankfurters: Effects of Non-Meat Ingredients and End-Point Temperature

Innawong, Bhundit 10 December 1998 (has links)
The effects of NaCl (1 and 2%), added-water (AW; 30 and 40%), milk protein hydrolysate (MPH; 1, 2 and 3%), and end-point cooking temperature (EPT; 71.1 and 76.7 C) were examined. Regardless of the formulation, all turkey-beef frankfurters contained less than 0.4% fat. As levels of NaCl in the formula increased, the frankfurters had lower (P< 0.05) penetration values (total energy and peak force) but higher shear stress and shear strain. In addition, higher salt levels resulted in lower cooking loss, moisture content, protein content, and darker frankfurters. Increasing AW level reduced (P<0.05) penetration values (total energy and peak force), shear stress, shear modulus, and hardness but increased cohesiveness. Higher levels of AW not only resulted in higher (P<0.05) moisture content but also resulted in higher cooking loss and purge loss. Higher AW products were lighter (P<0.05) in color and less red. Increasing the amount of MPH increased (P<0.05) shear stress and shear modulus but lowered shear strain. Higher MPH reduced cooking loss and produced (P<0.05) darker, more yellow, and less red frankfurters. Higher EPT increased (P<0.05) cooking loss, shear stress, and shear modulus but decreased penetration values (total energy and peak force), shear strain, and cohesiveness. Higher EPT produced lighter (P<0.05) colored frankfurters. There were some two and three-way independent variable interactions (P<0.05) for shear stress, shear strain, and cohesiveness. Of the four independent variables evaluated, AW and EPT most influenced textural properties. By using various combinations of these four independent variables, meat processors would have the ability to improve the quality characteristics of fat-free frankfurters. / Master of Science
22

The Effect of Cannabinoids and Cannabis on Mammary Epithelial Cell Function and Breast Milk Composition / EFFECT OF CANNABIS ON MAMMARY EPITHELIAL CELLS AND BREAST MILK

Josan, Chitmandeep January 2023 (has links)
Mammary gland (MG) is a dynamic organ that is essential for the production and secretion of breast milk. During pregnancy the MG undergoes a critical phase of remodeling, which is accompanied by the differentiation of mammary epithelial cells (MECs). During lactation, the MG requires high level of energy for proper folding of proteins in the secretory pathway, which takes place in the endoplasmic reticulum (ER). Limited evidence has been reported on the impact of cannabis or its components, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), on the differentiation of MECs. However, both THC and CBD have been reported to induce ER stress in various cell types, resulting in impacting cellular function. Furthermore, consequences of cannabis use in the perinatal period on breast milk composition have not been reported. Using the HC11 cell line, we investigated whether THC and CBD evoke ER stress in MECs resulting in the impaired cellular function. We also reported on the effects of cannabis use during pregnancy and lactation on the levels of macronutrients and bioactive factors in the breast milk of cannabis users. Relative to control, 10μM THC and 10μM CBD reduced mRNA levels of milk proteins (CSN2 and WAP) and lipid synthesizing enzymes (FASN, FABP4, PLIN2 and LPL), as well as whey acidic protein and lipid levels. In addition, 10μM THC, 10μM CBD, and the combination of 10μM THC + 10μM CBD significantly induced the expression of ER stress genes in HC11 cells. Furthermore, in the milk of women who used cannabis during pregnancy and lactation, the levels of secretory immunoglobulin A (SIgA) were decreased, relative to non-users. Altogether, our findings indicate that cannabis use in the perinatal period may have implications on breast milk composition and infant health. / Thesis / Doctor of Philosophy (Medical Science) / Breast milk is crucial to the nutrition and immunity of the newborn. It is produced by the mammary gland (MG), which is composed of mammary epithelial cells (MEC) that play a key role in producing and secreting proteins and factors into the milk. During pregnancy, the MG undergoes remodeling which is accompanied by differentiation of the MECs (change from unspecialized to a specialized stage that allows the MECs to produce milk proteins and other factors). The disruption in MEC differentiation can result in altered milk production and composition. Cannabis is used by women during pregnancy and breastfeeding. In this study, we investigated the impact of cannabinoids on the MEC differentiation and examined the effect of cannabis use in the perinatal period on the breast milk composition in humans. We reported that cannabinoids reduced the differentiation of MECs and maternal cannabis use during breastfeeding reduced levels of an essential immune factor.
23

Regulation of β-Casein Gene Expression by Octamer Transcription Factors and Utilization of β-Casein Gene Promoter to Produce Recombinant Human Proinsulin in the Transgenic Milk

Qian, Xi 01 January 2014 (has links)
β-Casein is a major milk protein, which is synthesized in mammary alveolar secretory epithelial cells (MECs) upon the stimulation of lactogenic hormones, mainly prolactin and glucocorticoids (HP). Previous studies revealed that the proximal promoter (-258 bp to +7 bp) of the β-casein gene is sufficient for induction of the promoter activity by HP. This proximal region contains the binding sites for the signal transducer and activator of transcription 5 (STAT5), glucocorticoid receptor (GR), and octamer transcription factors (Oct). STAT5 and GR are essential downstream mediators of prolactin and glucocorticoid signaling, respectively. This study investigated the functions of Oct-1 and Oct-2 in HP induction of β-casein gene expression. By transiently transfection experiment, we showed that individual overexpression of Oct-1 and Oct-2 further enhanced HP-induced β-casein promoter activity, respectively, while Oct-1 and Oct-2 knockdown significantly inhibited the HP-induced β-casein promoter activity, respectively. HP rapidly induced the binding of both Oct-1 and Oct-2 to the β-casein promoter, and this induction was not mediated by either increasing their expression or inducing their translocation to the nucleus. In MECs, Oct-2 was found to physically interact with Oct-1 regardless of HP treatment. However, HP induced physical interactions of Oct-1 or Oct-2 with both STAT5 and GR. Although the interaction between Oct-1 and Oct-2 did not synergistically stimulate HP-induced β-casein gene promoter activity, the synergistic effect was observed for the interactions of Oct-1 or Oct-2 with STAT5 and GR. The interactions of Oct-1 with STAT5 and GR enhanced or stabilized the binding of STAT5 and GR to the promoter. Abolishing the interaction between Oct-1 and STAT5 significantly reduced the hormonal induction of β-casein gene transcription. Thus, our study indicates that HP activate β-casein gene expression by inducing the physical interactions of Oct-1 and Oct-2 with STAT5 and GR in mouse MECs. There is a high and increasing demand for insulin because of the rapid increase in diabetes incidence worldwide. However, the current manufacturing capacities can barely meet the increasing global demand for insulin, and the cost of insulin production keeps rising. The mammary glands of dairy animals have been regarded as ideal bioreactors for mass production of therapeutically important human proteins. We tested the feasibility of producing human proinsulin in the milk of transgenic mice. In this study, four lines of transgenic mice were generated to harbor the human insulin gene driven by the goat β-casein gene promoter. The recombinant human proinsulin was detected in the milk by Western blotting and enzyme-linked immunosorbent assay. The highest expression level of human proinsulin was as high as 8.1 μg/µl in milk of transgenic mice at mid-lactation. The expression of the transgene was only detected in the mammary gland during lactation. The transgene expression profile throughout lactation resembled the milk yield curve, with higher expression level at middle lactation and lower expression level at early and late lactation. The blood glucose and insulin levels and major milk compositions of transgenic mice were not changed. The mature insulin derived from the milk proinsulin retained biological activity. Thus, our study indicates that it is practical to produce high levels of human proinsulin in the milk of dairy animals, such as dairy cattle and goat.
24

Involução da glândula mamária durante o final da lactação e período seco de cabras Saanen: respostas de sobrevivência celular ao estresse agudo e relações com a temperatura por infravermelho / Mammary gland involution during late lactation and dry period of Saanen goats: cellular survival responses to acute stress and relations with infrared temperature

Manica, Emanuel 07 February 2019 (has links)
Durante a vida reprodutiva de uma fêmea a glândula mamária passa por diversas modificações. O período seco é de extrema importância para a renovação celular do tecido mamário para a próxima lactação, ocorrendo, nessa fase, intensa apoptose nas células epiteliais mamárias. Com isso, acredita-se que os glicocorticoides podem inibir a expressão de genes relacionados à síntese de leite e síntese de proteínas do leite durante a involução mamária. Além disso, nas horas seguintes à interrupção de ordenha, as células epiteliais ainda sintetizam leite, a qual gera um acúmulo de leite na glândula mamária, aumento da pressão intramamária e pode causar a abertura do canal do teto, favorecendo a entrada de microrganismos patógenos, aumentando a temperatura superficial do úbere. Foram utilizadas cabras da raça Saanen submetidas ao processo de secagem aos 249 ± 8 dias de lactação. O primeiro estudo teve como objetivo avaliar o aumento de cortisol plasmático (via administração exógena do hormônio adrenocorticotrófico) sobre a expressão dos genes da via IGF-1R/PI3K/Akt/mTOR e proteínas do leite (LALBA, CSN2 e LF) no tecido mamário, e a composição das secreções mamárias durante o período inicial da secagem. Observou-se que o aumento do cortisol causou uma diminuição significativa na expressão relativa de IGF-1R. Porém, não apresentou efeito sobre os demais genes PI3K/Akt/mTOR e LALBA, CSN2 e LF. O período de secagem diminuiu significativamente a expressão de LALBA e CSN2 e aumentou a expressão de LF. Além disso, o cortisol aumentou significativamente a infiltração de células imunes e manteve a concentração de lactoferrina mais elevada nas secreções mamárias. Os componentes do leite não foram alterados com a administração de ACTH. No entanto, o período de secagem aumentou significativamente a porcentagem de gordura, lactose, proteína e extrato seco. O segundo estudo teve por objetivo avaliar a temperatura superficial do úbere e ocular através da temperatura por infravermelho e relaciona-las com a contagem de células somáticas durante o período de secagem. Assim, a temperatura superficial do úbere foi significativamente correlacionada com o status de saúde do úbere das cabras Saanen. Por fim, a temperatura por infravermelho detectou as alterações nas temperaturas superficiais e a suas relações com a contagem de células somáticas. / During the reproductive life of a female, the mammary gland undergoes several modifications. The dry period is of extreme importance for the cellular renewal of the mammary tissue for the next lactation, occurring, at this stage, intense apoptosis in the mammary epithelial cells. With this, it is believed that glucocorticoids can inhibit the expression of genes related to milk synthesis and milk protein synthesis during mammary involution. In the hours following the interruption of milking, the epithelial cells still synthesize milk, which generates an accumulation of milk in the mammary gland, increased intramammary pressure and can cause the opening of the roof canal favoring the entry of pathogenic microorganisms and increasing the udder superficial temperature. So, Saanen goats were submitted to the drying process at 249 ± 8 days of lactation. The first study aimed to evaluate the increase of plasma cortisol (via exogenous adrenocorticotrophic hormone administration) on the expression of IGF-1R/PI3K /Akt /mTOR and milk proteins (LALBA, CSN2 and LF) genes in mammary tissue, and the composition of the mammary secretions during the initial drying period. It was observed that increased cortisol caused a significant decrease in the relative expression of IGF-1R. However, it had no effect on the other PI3K/Akt/mTOR and LALBA, CSN2 and LF genes. The drying period significantly decreased LALBA and CSN2 expression and increased LF expression. In addition, cortisol significantly increased the infiltration of immune cells and maintained the higher concentration of lactoferrin in mammary secretions. Milk components were not altered with ACTH administration. However, the drying period significantly increased the percentage of fat, lactose, protein and dry extract. The second study aimed to evaluate the udder and ocular surface temperature through infrared temperature and correlates them with the somatic cell count during the drying period. Thus, the surface temperature of the udder was significantly correlated with the health status of the udder of the Saanen goats. Finally, the infrared temperature detected changes in surface temperatures and their relationships with somatic cell counts.
25

Variation in milk protein composition and its importance for the quality of cheese milk /

Wedholm, Anna, January 2008 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2008. / Härtill 5 uppsatser.
26

Estudo do polimorfismo da kappa- caseína e alfa-lactoalbumina em bovinos Girolando, do Brasil e Siboney, de Cuba

FREITAS, Soraya Farias de Andrade 17 July 2013 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-05-18T12:44:39Z No. of bitstreams: 1 Soraya Farias de Andrade Freitas.pdf: 720574 bytes, checksum: 5bdec2199a6c7a1051ac90567718753f (MD5) / Made available in DSpace on 2017-05-18T12:44:39Z (GMT). No. of bitstreams: 1 Soraya Farias de Andrade Freitas.pdf: 720574 bytes, checksum: 5bdec2199a6c7a1051ac90567718753f (MD5) Previous issue date: 2013-07-17 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Milk is a food of nutritional and functional importance for all phases of life; however, of all constituents, the fat and protein components are considered to be the most economical value within milk quality payment programs. This fact suggests a greater importance given to these constituents by the main actors of the milk production chain within the economic scenario (MADALENA, 2000). Dürr (2004) reports that milk fat and protein concentrations vary mainly depending on the nutritional management and genetic potential of the animals. As a consequence of the genetic differences responsible for the variation of 25% of the total milk production and 50% in the variations of fat, protein and non-greasy solids (GONYON et al., 1987) ). According to Bonfatti et al. (2010), it is estimated that the additive genetic variance for milk composition characteristics is between 14 and 39% of the total variance. In relation to the polymorphisms of the genes coding for the main milk proteins, such as caseins, β-Lg and α-La, these became markers of interest in milk production, composition and processing. They are excellent models for understanding the behavior of the dairy raw material during the industrial process, since they are closely related to the milk casein fraction, the main protein portion involved with the high yield in the production of cheeses and other derivatives. In addition, genetic polymorphisms of milk proteins are frequently used for the characterization of several breeds of animal production (CAROLI et al., 2010). In order to promote improvements in the genetics of milk production, composition and processing characteristics, research in the field of molecular biology has made it possible to map and identify genomic, transcriptomic and proteomic levels of polymorphisms that contribute to variations in milk composition , In this way, the process of selection of animals in breeding programs. In view of the above, the objective of this research was to study the genetic polymorphisms of kappa-casein and alpha-lactalbumin in cattle of the Girolando and Siboney races / O leite é um alimento de importância nutricional e funcional para todas as fases da vida, entretanto, de todos os constituintes, os componentes gordura e proteína são considerados os de maior valor econômico dentro dos programas de pagamento de leite por qualidade. Esse fato sugere uma maior importância dada a esses constituintes pelos principais atores da cadeia produtiva leiteira dentro do cenário econômico (MADALENA, 2000). Dürr (2004) relata que as concentrações de gordura e proteína do leite variam principalmente em função do manejo nutricional e potencial genético dos animais. Desta forma, como principal fator de variação têm-se os efeitos das diferenças genéticas responsáveis pela variação de 25% do total da produção de leite e 50% nas variações dos teores de gordura, proteína e sólidos não gordurosos (GONYON et al., 1987). Segundo Bonfatti et al. (2010), estima-se que a variância genética aditiva para as características de composição do leite encontra-se entre 14 e 39% da variância total. Com relação aos polimorfismos dos genes que codificam as principais proteínas do leite, como as caseínas, β-Lg e α-La, estes se tornaram marcadores de interesse na produção, composição e beneficiamento do leite. São excelentes modelos de compreensão do comportamento da matéria prima láctea durante o processo industrial, já que estão intimamente relacionados à fração caseínica do leite, principal porção proteica envolvida com o alto rendimento na produção de queijos e demais derivados. Além disso, os polimorfismos genéticos das proteínas lácteas são frequentemente utilizados para a caracterização de diversas raças de produção animal (CAROLI et al., 2010). Deste modo, para promover melhorias na genética das características de produção, composição e beneficiamento do leite, pesquisas no ramo da biologia molecular têm possibilitado realizar o mapeamento e identificação em nível genômico, transcriptômico e proteômico dos polimorfismos que contribuem para variações na composição do leite facilitando, desta forma, o processo de seleção dos animais em programas de melhoramento genético. Diante do exposto, o objetivo desta pesquisa foi estudar os polimorfismos genéticos da kappa-caseína e alfa-lactoalbumina em bovinos das racas Girolando e Siboney.
27

Cytotoxic lymphocytes in children's cow's milk sensitive enteropathy of delayed type

Augustin, M. (Merja) 10 May 2005 (has links)
Abstract Food hypersensitivities are becoming increasingly common worldwide. Previous studies indicate that cell mediated immunity has a role in delayed paediatric gastrointestinal food hypersensitivities, but the exact pathogenetic mechanisms are unknown. Cytotoxic activation of T-lymphocytes is known to play an important role in the pathogenesis of celiac disease (CD). The pathogenetic mechanisms of cow's milk protein sensitive enteropathy (CMSE) are largely unknown. CMSE is a non-IgE related type of food hypersensitivity with variable gastrointestinal symptoms but no visible mucosal abnormalities on light microscopy. The diagnosis is based on an open or blinded elimination/challenge test, as the endoscopic, histological and laboratory findings are generally non-specific. This thesis aims to characterize the role of lymphocyte cytotoxicity in the pathogenesis and diagnosis of CMSE in preschool and school aged children, including comparison with CD where the pathogenetic significance of cytotoxicity is well established. The study cohort consisted of 151 children, including 57 with untreated CMSE, 18 with treated CMSE, 24 with CD, and 52 controls. Using immunohistochemistry, the mucosal expressions of cytotoxic T cell-restricted intracellular antigen type 1 (TIA-1), perforin, granzyme A and B were analysed in the duodenal bulb and descending duodenum. Intraepithelial T-lymphocytes were labelled with CD3, alpha/beta and gamma/delta T cell receptor antigens. To determine the rates of overall and epithelial apoptosis as well as proliferation, the immunohistochemical TUNEL technique, M30 and Ki-67 antibodies were used. Serum levels of granzymes, CD30 and soluble Fas were studied using ELISA method. The number of intraepithelial lymphocytes with TIA-1, perforin and granzyme A containing granules was increased in CMSE. This increase was related to antigen challenge and not a constitutional abnormality. The cytotoxic reaction in CMSE differed from that in CD by being of lesser magnitude, concerning predominantly the descending duodenum and not showing signs of cytotoxicity related epithelial destruction. The serum levels of GrA, GrB and CD30 were increased in both CMSE and CD, correlating with the number of duodenal CD3+, alpha/beta and gamma/delta+ intraepithelial lymphocytes. The results strongly support the role of cell-mediated immunity in the pathogenesis of CMSE. Mucosal cytotoxic activation seems to be manifested by the release of cytoxicity related proteins in serum. This provides a new approach to the monitoring of intestinal immune activation which could help in diagnosis and in objectively monitored treatment response.
28

Destabilization of protein-based emulsions caused by bacteriostatic emulsifiers / タンパク質で乳化したエマルションの静菌性乳化剤による不安定化

Matsumiya, Kentaro 24 March 2014 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(農学) / 乙第12820号 / 論農博第2793号 / 新制||農||1025(附属図書館) / 学位論文||H26||N4815(農学部図書室) / 31307 / 京都大学農学研究科農学専攻 / (主査)教授 松村 康生, 教授 裏出 令子, 教授 安達 修二 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
29

Development and Validation of a Light Weight, Energy Dense, Ready to Eat (RTE) Bar

Heick, Jacob Wilhelm-Maria 01 December 2010 (has links) (PDF)
DEVELOPMENT AND VALIDATION OF A LIGHT WEIGHT, ENERGY DENSE, READY TO EAT (RTE) BAR Jacob Wilhelm-Maria Heick Providing additional calories in the form of an RTE bar to endurance athletes will increase performance and muscle re-synthesis, reduce muscle breakdown, and shorten recovery time. An RTE bar containing a blend of dairy proteins and carbohydrates will create a product with superior functionality, including bioactive and immunity enhancing properties from dairy derived ingredients. The protein will provide benefits in the form of easily digestible calories, essential amino acids and physical satiate. A formulation was developed and optimized, resulting in a final product that meets the required nutritional profile: 400kcal, 25grams protein per 100 gram serving size. The desired physical characteristics were achieved through processing by both conventional baking and freeze drying. The latter method improves the stability and functionality of the RTE bar. In order to meet the protein requirements of the RTE bar without compromising sensory properties, a unique protein source was developed. Using high concentrations of conventional protein sources like Whey Protein Concentrate (WPC) resulted in stale off-flavors and unappealing textures. Milk Protein Precipitate (MPP) was developed for this formulation. MPP is a curd-like ingredient created through the combined heat and acid precipitation of dairy proteins. MPP can be used effectively in high concentrations provides a subtle dairy flavor. MPP delivers a balance of casein and whey, similar to that found in milk. The effectiveness of the RTE bar formulation as a post exercise recovery food was evaluated in a human studies experiment conducted on the Cal Poly campus. The human subjects study utilized 34 Cal Poly students in a single-blind cross-over design experiment. The study compared the effects of this high protein RTE bar against a calorically equal carbohydrate bar. The bars were administered after subjects completed the pre-assigned hikes on three consecutive days. Following the cross-over design, subjects received the alternate bar in the second period of the experiment. Several blood markers involved in metabolism and inflammation were measured before and after the two treatment periods. No blood marker showed a statistically significant difference between bars, but several trends were observed. Body weight and fat percent were also unaffected by bar composition.
30

Impact of High Pressure Processing on Immunoreactivity and SomePhysico-chemical Properties of Almond Milk

Dhakal, Santosh 19 September 2013 (has links)
No description available.

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