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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.
211

Efeito da solução salina hipertônica nas lesões resultantes da isquemia/reperfusão hepática: estudo experimental em ratos / Effect of hypertonic saline solution during ischemia/reperfusion injury in rat liver

Estela Regina Ramos Figueira 24 June 2008 (has links)
Introdução: A lesão de isquemia/reperfusão do fígado é caracterizada pelo agravamento da lesão isquêmica hepatocelular quando o órgão é revascularizado, podendo originar, nos casos mais graves, uma reação inflamatória sistêmica com lesão de órgãos à distância. O controle desse fenômeno é importante no transplante de fígado, nas cirurgias de ressecção hepática e no choque hemorrágico. A administração de soluções salinas hipertônicas têm se mostrado eficaz no tratamento do choque hemorrágico, pois melhora as alterações hemodinâmicas e, possivelmente, apresenta uma ação antiinflamatória. Neste trabalho foram avaliados os efeitos locais e sistêmicos da administração da solução salina hipertônica na lesão de isquemia/reperfusão hepática em ratos. Métodos: Enquanto 14 ratos Wistar machos, dos 56 utilizados no estudo, compuseram o grupo controle, grupo C; os demais, que foram submetidos à uma hora de isquemia hepática e 4 horas de reperfusão, compuseram outros grupos de 14 animais: o grupo ST, animais que não receberam tratamento; o grupo SSF, animais que receberam 34 mL/kg de NaCl 0,9%, por via endovenosa, 15 minutos antes da reperfusão; o grupo SSH, animais que receberam 4 mL/kg de NaCl 7,5%, 15 minutos antes da reperfusão. Após 4 horas de reperfusão, os materiais foram coletados para análise. Foram realizadas as dosagens das transaminases AST e ALT, a avaliação das funções oxidativas e fosforilativas mitocondriais, a dosagem das interleucinas IL-6 e IL-10, as análises teciduais pulmonares e a análise histológica do fígado isquêmico e não isquêmico. Resultados: Quando comparado aos grupos ST e SSF, o grupo SSH apresentou elevação dos níveis de AST e ALT significantemente menores; preservação da função mitocondrial tanto dos lobos isquêmicos, como dos não isquêmicos, significantemente melhor; elevação dos níveis de IL-6 e IL-10 sem significância estatística; aumento da permeabilidade vascular pulmonar significantemente menor; e elevação da atividade da mieloperoxidase pulmonar sem significância estatística. Em relação à análise histológica da lesão de isquemia/reperfusão hepática, o escore da lesão do grupo SSH foi significantemente menor que o da lesão do grupo C; entretanto, quando comparados os três grupos submetidos à isquemia hepática ST, SSH e SSF não se observaram diferenças significantes estatisticamente. Conclusão: A administração da solução salina hipertônica a 7,5% na isquemia/reperfusão hepática normotérmica melhorou as lesões hepáticas locais e as lesões à distância, principalmente pulmonares / Introduction: During liver ischemia, the drop in mitochondrial energy production leads to cellular damage, which is aggravated during restoration of blood supply. Besides local hepatic injury, the ischemia/reperfusion process can trigger a systemic inflammatory syndrome producing remote organ damage. To control these alterations in clinical conditions like liver transplantation, liver resections and hypovolemic shock, is crucial to achieve proper patient management. Aim: To evaluate the effect of the sodium chloride hypertonic solution on prevention of local and systemic injury during partial liver ischemia/reperfusion. Methods: Animals underwent partial warm liver ischemia/reperfusion. Fity six Wistar male rats were randomly allocated into four groups. Fourteen animals were submitted to sham operation and allocated to C group; 42, submitted to one hour of liver ischemia followed by 4 hours of reperfusion, were allocated in three additional groups: ST group, 14 animals that received no treatment; SSF group, 14 animals that received NaCl 0.9%, 34 mL/kg, intravenously; SSH group, animals that received NaCl 7.5%, 4 mL/kg, intravenously. Blood and tissue samples were collected four hours after reperfusion, when animals were killed. Blood samples were collected to determinate AST, ALT, IL-6 and IL-10 levels. Liver and pulmonary tissues were assembled for liver histology and for liver mitochondrial phosphorylation, pulmonary vascular permeability and myeloperoxidase analyzes. Results: Hypertonic saline solution showed beneficial effects in the treatment of liver ischemia/reperfusion injury. SSH group presented elevation of AST and ALT plasma levels significantly lower than ST and SSF groups. A significant reduction on mitochondrial dysfunction was observed in SSH group compared with ST and SSH groups. Elevation in serum IL-6 and IL-10 was similar among ST, SSF and SSH groups. Pulmonary vascular permeability was significantly lower in group SSH compared with ST and SSF groups. No differences in myeloperoxidase activity were observed among these three groups. Histological score for liver ischemia/reperfusion injury was significantly lower in SSH group compared to ST group, however no differences were observed between SSH and SSF groups. Conclusion: Administration of hypertonic saline solution in an experimental rat model of liver ischemia-reperfusion ameliorated local and systemic injuries
212

Avaliação da administração intravenosa de solução salina hipertônica 7,5% como estratégia para melhorar a perfusão do tumor e a entrega de moléculas em modelos tumorais em camundongos / Evaluation of hypertonic saline solution 7,5% intravenous administration as a potential strategy to enhance tumor perfusion as well as molecular delivery in mice tumor models

Gonzalez, Angelica Maria Patiño 20 December 2016 (has links)
A administração intravenosa de solução salina hipertônica (HSS) induz alterações sistêmicas circulatórias como o aumento da pressão arterial e do volume circulante efetivo, além de ter efeitos locais sobre a microcirculação. No presente estudo foram analisados os efeitos produzidos pela administração de solução salina hipertônica 7,5% sobre a hemodinâmica do tumor através de estudos de imagem funcional e posteriormente, foi avaliado o seu potencial de otimizar a entrega de moléculas no tumor. A velocidade do sangue nos vasos tumorais estimada por Ultrassom Color Doppler foi aumentada após a injeção da HSS em comparação ao controle PBS em tumores de melanoma (B16F10 (p=0,019), SK-MEL-147 (p =0,028)) e de mama (4T1 (p=0,015)). Este mesmo efeito não foi observado nas artérias segmentarias do rim (p=0,476). Ultrassonografia com contraste por microbolhas (CEUS) foi realizada em xenoenxertos de tumor de melanoma (B16F10), carcinoma de cólon (HCT-116) e mama (MDA-MB-231), e como controle foi realizada imagem no rim e no músculo nos animais portadores destes tipos tumorais (n=3 por grupo). Após a injeção da HSS, o volume relativo de sangue foi aumentado nos tumores B16F10 (p=0,022) e HCT-116 (P = 0,039), mas o mesmo não foi observado com o tumor MDA-MB-231 (p=0,186). Além disso, não houve alterações nos tecidos normais (rim p = 0,957; músculo p = 0,104). Todos os testes estatísticos foram bicaudais. Quando a HSS foi utilizada como veículo para entrega de moléculas de baixo peso molecular como cisplatina e doxorrubicina no tratamento de tumores B16F10 e 4T1 respectivamente, não houve aumento da eficácia terapêutica, avaliada através do crescimento tumoral e peso dos tumores. O efeito da HSS sobre a retenção de macromoléculas nos tumores SK-Mel- 147 e 4T1, avaliado através de imagem por epifluorescência do contraste ótico IR-783, não foi suficientemente notório para rejeitar a hipótese nula. Assim, a HSS induz um aumento transitório na velocidade do sangue e do volume sanguíneo, de maneira relativamente seletiva para os tumores avaliados, com exceção do MDA-MB-231. Portanto, esta pode ser uma estratégia útil para aumentar a entrega de moléculas e otimizar tanto o efeito terapêutico, quanto o diagnóstico por imagem / Intravenous administration of Hypertonic saline solution (HSS) induces systemic circulatory changes including blood pressure rising, effective circulating volume increase as well as local effects on microvasculature. We analyzed the effects produced by Hypertonic Saline 7,5% administration on tumor hemodynamics through functional imaging studies as well as whether it enhances molecular delivery in tumor tissue when used as a vehicle. Blood velocity assessed by Color Doppler Ultrasound was increased after HSS injection compared to PBS in the following tumors: B16F10 (p=0,019), SKMEL- 147 (p=0,028) and 4T1 (p=0,015). No statistical difference was observed on the segmental kidney arteries (p=0,476). Dynamic Contrast enhanced ultrasound (CEUS) was done in B16F10, HCT-116 and MDA-MB-231 tumor xenografts, kidney and muscle tissues (n=3 per group). After HSS injection, relative blood volume was increased in B16F10 (p=0,022) and HCT-116 (p=0,039) but not on MDA-MB-231 (p=0,186). Changes on normal tissues were not statistically different (kidney p=0,957; muscle p=0,104). All statistical tests were two-sided. Administration of HSS as a vehicle for low molecular weight molecules cisplatin and doxorubicin in the treatment of B16F10 and 4T1 tumors respectively had no significant improvement of therapeutic efficacy, estimated by tumor growth and tumor weight measurements. Effect of HSS over retention of macromolecules in tumors SK-Mel-147 and 4T1, evaluated by epifluorescence imaging of the optical contrast IR- 783 was not large enough to reject the null hypothesis. HSS induces a transient increase in velocity of the blood as well as the blood volume that is relatively selective for the evaluated tumors with exception of MDA-MB-231. Data suggest that HSS administration might be a useful strategy to increase the delivery of molecules and optimize both therapy and diagnostic imaging
213

Respostas de lâminas de irrigação e tipos de adubação no crescimento e produção do Pinhão-manso em condições de campo. / Growth and production of the Jatropha Curcas fertilized and irrigated with saline water under field conditions

NÓBREGA, Jerônimo Andrade da. 30 May 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-05-30T20:26:53Z No. of bitstreams: 1 JERÔNIMO ANDRADE DA NÓBREGA 1.PDF: 26585385 bytes, checksum: 048ff214808b8d928b95ac6d27b1ca5f (MD5) / Made available in DSpace on 2018-05-30T20:26:53Z (GMT). No. of bitstreams: 1 JERÔNIMO ANDRADE DA NÓBREGA 1.PDF: 26585385 bytes, checksum: 048ff214808b8d928b95ac6d27b1ca5f (MD5) Previous issue date: 2010-08 / O pinhão-manso (Jatropha curcas L.) é uma planta produtora de óleo atualmente considerada como alternativa para a produção de biodiesel. Objetivou-se com esta pesquisa avaliar os efeitos da aplicação de diferentes níveis de reposição da evapotranspiração, através da irrigação com água salina, e efeitos da adubação orgânica e mineral no cultivo do pinhão-manso em condições de campo. O experimento foi desenvolvido na Fazenda Barra, no município de Santa Luzia, no semiarido paraibano. O delineamento estatístico utilizado foi em blocos casualizados, em um esquema de parcelas subdivididas, com quatro repetições. Foram estudados cinco níveis de reposição de água (25; 50; 75; 100 e 125% da evapotranspiração de referência) e três tipos de adubação (orgânica, mineral e fertilidade natural do solo, isto é, sem aplicação de adubo). As variáveis avaliadas foram: altura das plantas; diâmetro do caule; número de folhas; peso das sementes, dos frutos e da casca, e no fim do experimento, foi realizada uma análise foliar objetivando-se observar o acúmulo de nutrientes nas folhas. As lâminas de irrigação e o tipo de adubação exerceram, em determinado período de avaliação ou em todos eles, efeitos significativos nos parâmetros de crescimento e no número de folhas. As lâminas de irrigação não afetaram o peso das sementes, dos frutos nem da casca, enquanto a adubação causou efeito altamente significativo. As lâminas de irrigação promoveram efeito significativo no teor de nutrientes das folhas no final do experimento, apenas nos elementos sódio e nitrogénio, enquanto o efeito das adubações não foi significativo em nenhum dos elementos. As diferenças no teor de nutrientes das folhas entre as lâminas de 25% e 75% da ETo foram significativas apenas para os elementos N e Na; já nas médias dos tratamentos das adubações orgânica e mineral e sem adubação, não ocorreram diferenças estatísticas. / The Jatropha curcas is a oil producer plant now considered as an alternative for biodiesel production. This research aimed to evaluate the effects of the application of different leveis of replacement of the evapotranspiration, through the irrigation with saline water, and effects of the organic and chemical manuring in the cultivation of the Jatropha curcas under field conditions. The experiment was developed in the Farm Barra, in the municipal district of Santa Luzia, in the Paraíba semi-arid. The used statistical design was in randomized blocks, in an scheme of subdivided plots, with four replications. Five leveis of replacement of water (25; 50; 75; 100 and 125% of the reference evapotranspiration) and three manuring types (organic, mineral and natural fertility of the soil, that is, without fertilizer application) were studied. The appraised variables were: plants height; stem diameter, number of leaves, the seeds, fruits and peei weight, and at the end of the experiment a leave analysis was accomplished, aiming to observe the accumulation of nutrients in the leaves. The irrigation water depths and the manuring type exercised, in a certain evaluation period or in ali of them, significant effects on the growth parameters and on the number of leaves. The irrigation water depths didn't affect the weight of the seeds, of the fruits and of the peei, while the manuring caused effect highly significant. The irrigation water depths promoted significant effect on the content of nutrients of the leaves by the end of the experiment, just in the elements sodium and nitrogen, while the effect of the manurings was not significant in none of the elements. The differences in the content of nutrients of the leaves among the water depths of 25% and 75% of ETo were significant just for the elements N and Na; already in the mean of the treatments of the organic and chemical manurings and without manuring, didn't happen statistical differences.
214

Homology-Based Functional Proteomics By Mass Spectrometry and Advanced Informatic Methods

Liska, Adam J. 16 November 2003 (has links) (PDF)
Functional characterization of biochemically-isolated proteins is a central task in the biochemical and genetic description of the biology of cells and tissues. Protein identification by mass spectrometry consists of associating an isolated protein with a specific gene or protein sequence in silico, thus inferring its specific biochemical function based upon previous characterizations of that protein or a similar protein having that sequence identity. By performing this analysis on a large scale in conjunction with biochemical experiments, novel biological knowledge can be developed. The study presented here focuses on mass spectrometry-based proteomics of organisms with unsequenced genomes and corresponding developments in biological sequence database searching with mass spectrometry data. Conventional methods to identify proteins by mass spectrometry analysis have employed proteolytic digestion, fragmentation of resultant peptides, and the correlation of acquired tandem mass spectra with database sequences, relying upon exact matching algorithms; i.e. the analyzed peptide had to previously exist in a database in silico to be identified. One existing sequence-similarity protein identification method was applied (MS BLAST, Shevchenko 2001) and one alternative novel method was developed (MultiTag), for searching protein and EST databases, to enable the recognition of proteins that are generally unrecognizable by conventional softwares but share significant sequence similarity with database entries (~60-90%). These techniques and available database sequences enabled the characterization of the Xenopus laevis microtubule-associated proteome and the Dunaliella salina soluble salt-induced proteome, both organisms with unsequenced genomes and minimal database sequence resources. These sequence-similarity methods extended protein identification capabilities by more than two-fold compared to conventional methods, making existing methods virtually superfluous. The proteomics of Dunaliella salina demonstrated the utility of MS BLAST as an indispensable method for characterization of proteins in organisms with unsequenced genomes, and produced insight into Dunaliella?s inherent resilience to high salinity. The Xenopus study was the first proteomics project to simultaneously use all three central methods of representation for peptide tandem mass spectra for protein identification: sequence tags, amino acids sequences, and mass lists; and it is the largest proteomics study in Xenopus laevis yet completed, which indicated a potential relationship between the mitotic spindle of dividing cells and the protein synthesis machinery. At the beginning of these experiments, the identification of proteins was conceptualized as using ?conventional? versus ?sequence-similarity? techniques, but through the course of experiments, a conceptual shift in understanding occurred along with the techniques developed and employed to encompass variations in mass spectrometry instrumentation, alternative mass spectrum representation forms, and the complexities of database resources, producing a more systematic description and utilization of available resources for the characterization of proteomes by mass spectrometry and advanced informatic approaches. The experiments demonstrated that proteomics technologies are only as powerful in the field of biology as the biochemical experiments are precise and meaningful.
215

Irrigação do feijão-de-corda com água salina em diferentes estádios de desenvolvimento e seus efeitos na planta e no solo. / Irrigação do feijão-de-corda com água salina em diferentes estádios de desenvolvimento e seus efeitos na planta e no solo.

Neves, Antônia Leila Rocha January 2008 (has links)
NEVES, Antônia Leila Rocha. Irrigation of cowpea with saline water at different growth stages and their effects on the plant and soil. 2008. 119 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia Agrícola. 2008 / Submitted by demia Maia (demiamlm@gmail.com) on 2016-06-13T14:53:10Z No. of bitstreams: 1 2008_dis_alrneves.pdf: 903212 bytes, checksum: 4298d42aacb4a0815d2c06c72d764de8 (MD5) / Approved for entry into archive by demia Maia (demiamlm@gmail.com) on 2016-06-13T14:57:22Z (GMT) No. of bitstreams: 1 2008_dis_alrneves.pdf: 903212 bytes, checksum: 4298d42aacb4a0815d2c06c72d764de8 (MD5) / Made available in DSpace on 2016-06-13T14:57:22Z (GMT). No. of bitstreams: 1 2008_dis_alrneves.pdf: 903212 bytes, checksum: 4298d42aacb4a0815d2c06c72d764de8 (MD5) Previous issue date: 2008 / The sensitivity of crops to salinity often changes from one growth stage to another. Cowpea [Vigna unguiculata (L.) Walp.] is an important crop specie cultivated in different semi-arid regions of the world. The objective of this work was to evaluate the effect of the irrigation with saline water, applied at different growth development stages of cowpea. The experiment was set up in the field, during the dry season. A completely randomized block design, with five treatments (T1, T2, T3, T4 and T5) and five repetitions, was adopted. The distance between lines and plants were 0.8 m and 0.3 m, respectively, with two plants per hole. The treatments studied were: T1 - Groundwater with electrical conductivity (ECw) of 0.8 dS m-1 during the whole crop cycle; T2 - Saline water (ECw = 5.0 dS m-1) during the whole crop cycle, starting after germination; T3 - Saline water (ECw = 5.0 dS m-1) from sowing until the 22th day after sowing (germination and initial growth) and groundwater in remaining stages of the crop cycle; T4 - Saline water (ECw = 5.0 dS m-1) from the 23th to the 42nd day after germination (intense growth and pre-flowering), and groundwater irrigation for the remaining growth stages. T5 - Groundwater from sowing to the 42nd day after sowing and saline water (ECw = 5.0 dS m-1) during flowering and pod-filling stages. Soil coverage, gas exchange, vegetative growth and crop yield were measured. The mineral concentration and quantity of nutrient removed from the soil, as well as the nutrient use efficiency and salt accumulation in soil were also determined. The irrigation with combination of groundwater and saline water reduced the salt accumulation in soil, in relation to continuous use of saline water. The continuous application of water with ECw of 5.0 dS m-1 (T2) reduced the rates of photosynthesis and transpiration, in relation to the well water (T1). Plants of the treatment 3 showed reduction in gas exchanges only in the first measurement, while the saline water application in other growth stages (T 4 and T5) did not provoke significant reductions in leaf in the gas exchanges of the plants. It was found that the continuous use of saline water inhibits plant growth, while the irrigation with saline water during germination and initial growth causes retardation in plant development. For treatments 2 and 3, reduction in the number of pods and in seed production was verified. Irrigation with saline water from the 23rd to the 42nd day (T4) and from the 43rd to the 63rd (T5) day after sowing did not affect reproductive and vegetative growth, but the saline water application in the pre-flowering (T4) caused anticipation of reproductive cycle. Cowpea plants removed the minerals analyzed in the following decreasing sequence: N > K > Cl > Ca > Na > P > Fe > Zn > Mn > Cu, but the continuous use of saline water (T2) reduced the total extracted for the most nutrients, except for Na e Cl. The minerals Na, Cl, K, Ca, Fe and Mn were distributed preferentially to vegetative plant parts, while the most of N and P were exported in the pods. The irrigation with saline water during germination and initial growth stage (T3) reduced the mineral use efficiency of most of analyzed nutrients. The continuous application of saline water (T2) reduced the agronomic efficiency of the fertilizer application (N, P and K), but it did not affect the nutrient use efficiency by the plants. / A sensibilidade à salinidade varia com o estádio de desenvolvimento da cultura. O feijão-de-corda [Vigna unguiculata (L.) Walp.] constitui uma das principais culturas, em diversas regiões semi-áridas do mundo. Avaliou-se o efeito da irrigação com água salina, aplicada em diferentes estádios de desenvolvimento de plantas de feijão-de-corda. O experimento foi conduzido no campo, e obedeceu ao delineamento em blocos ao acaso, com cinco tratamentos (T1, T2, T3, T4 e T5) e cinco repetições. O feijão-de-corda foi cultivado no espaçamento de 0,8 m entre linhas e 0,3 m entre plantas, com duas plantas por cova. Os tratamentos utilizados foram: T1 - plantas irrigadas com água do poço (CEa de 0,8 dS m-1) durante todo o ciclo; T2 - Água salina com CEa de 5,0 dS m-1, com aplicação iniciada após a germinação e permanecendo até o final do ciclo; T3 - Água salina com CEa de 5,0 dS m-1, da semeadura até 22 dias após o plantio (DAP), correspondendo às fases de germinação e crescimento inicial, e água do poço no restante do ciclo; T4 - Água salina com CEa de 5,0 dS m-1, aplicada de 23 a 42 DAP (fase de intenso crescimento vegetativo até a pré-floração), e água do poço nas demais fases do ciclo; T5 - Água do poço da semeadura até 42 DAP e água salina (CEa de 5,0 dS m- 1) aplicada a partir dos 43 DAP (floração e frutificação). Foram avaliadas a cobertura vegetal do solo, crescimento vegetativo, fotossíntese, transpiração, condutância estomática, produtividade, partição de matéria seca, os teores, os totais extraídos e a distribuição dos nutrientes na planta, a eficiência nutricional, eficiência no uso da água e o acúmulo de sais no solo. A irrigação com a combinação de água do poço com água salina reduziu o acúmulo de sais no solo, em relação ao T2. O T2 reduziu as taxas de fotossíntese e transpiração, em relação ao T1. O T3 provocou redução das trocas gasosas somente na primeira medição, enquanto, que similar aplicação nos outros estádios (T4 e T5) não provocou reduções significativas nas trocas gasosas das plantas. O T2 inibiu o crescimento vegetativo da planta, enquanto o T3 provocou retardo no desenvolvimento da planta. Os tratamentos T2 e T3 provocaram reduções significativas no número de vagens e na produção de sementes por planta, em relação aos demais tratamentos. Por outro lado, os tratamentos T4 e T5 não afetaram o crescimento e a produtividade da cultura, sendo que o T4 causou aceleração no ciclo reprodutivo da cultura. Os minerais foram extraídos pelo feijão-de-corda na seguinte ordem decrescente: N > K > Cl > Ca > Na > P > Fe > Zn > Mn > Cu, no entanto, o T2 reduziu a extração da maioria dos elementos analisados, com exceção do Na e Cl. Os minerais Na, Cl, K, Ca, Fe e Mn permaneceram preferencialmente nas partes vegetativas enquanto N e P foram exportados em maiores proporções pelos frutos. O T3 reduziu a eficiência de utilização da maioria dos nutrientes. O T2 reduziu a eficiência agronômica de utilização de N, P e K, entretanto não afetou a eficiência de utilização dos nutrientes extraídos pelas plantas.
216

Avaliação da administração intravenosa de solução salina hipertônica 7,5% como estratégia para melhorar a perfusão do tumor e a entrega de moléculas em modelos tumorais em camundongos / Evaluation of hypertonic saline solution 7,5% intravenous administration as a potential strategy to enhance tumor perfusion as well as molecular delivery in mice tumor models

Angelica Maria Patiño Gonzalez 20 December 2016 (has links)
A administração intravenosa de solução salina hipertônica (HSS) induz alterações sistêmicas circulatórias como o aumento da pressão arterial e do volume circulante efetivo, além de ter efeitos locais sobre a microcirculação. No presente estudo foram analisados os efeitos produzidos pela administração de solução salina hipertônica 7,5% sobre a hemodinâmica do tumor através de estudos de imagem funcional e posteriormente, foi avaliado o seu potencial de otimizar a entrega de moléculas no tumor. A velocidade do sangue nos vasos tumorais estimada por Ultrassom Color Doppler foi aumentada após a injeção da HSS em comparação ao controle PBS em tumores de melanoma (B16F10 (p=0,019), SK-MEL-147 (p =0,028)) e de mama (4T1 (p=0,015)). Este mesmo efeito não foi observado nas artérias segmentarias do rim (p=0,476). Ultrassonografia com contraste por microbolhas (CEUS) foi realizada em xenoenxertos de tumor de melanoma (B16F10), carcinoma de cólon (HCT-116) e mama (MDA-MB-231), e como controle foi realizada imagem no rim e no músculo nos animais portadores destes tipos tumorais (n=3 por grupo). Após a injeção da HSS, o volume relativo de sangue foi aumentado nos tumores B16F10 (p=0,022) e HCT-116 (P = 0,039), mas o mesmo não foi observado com o tumor MDA-MB-231 (p=0,186). Além disso, não houve alterações nos tecidos normais (rim p = 0,957; músculo p = 0,104). Todos os testes estatísticos foram bicaudais. Quando a HSS foi utilizada como veículo para entrega de moléculas de baixo peso molecular como cisplatina e doxorrubicina no tratamento de tumores B16F10 e 4T1 respectivamente, não houve aumento da eficácia terapêutica, avaliada através do crescimento tumoral e peso dos tumores. O efeito da HSS sobre a retenção de macromoléculas nos tumores SK-Mel- 147 e 4T1, avaliado através de imagem por epifluorescência do contraste ótico IR-783, não foi suficientemente notório para rejeitar a hipótese nula. Assim, a HSS induz um aumento transitório na velocidade do sangue e do volume sanguíneo, de maneira relativamente seletiva para os tumores avaliados, com exceção do MDA-MB-231. Portanto, esta pode ser uma estratégia útil para aumentar a entrega de moléculas e otimizar tanto o efeito terapêutico, quanto o diagnóstico por imagem / Intravenous administration of Hypertonic saline solution (HSS) induces systemic circulatory changes including blood pressure rising, effective circulating volume increase as well as local effects on microvasculature. We analyzed the effects produced by Hypertonic Saline 7,5% administration on tumor hemodynamics through functional imaging studies as well as whether it enhances molecular delivery in tumor tissue when used as a vehicle. Blood velocity assessed by Color Doppler Ultrasound was increased after HSS injection compared to PBS in the following tumors: B16F10 (p=0,019), SKMEL- 147 (p=0,028) and 4T1 (p=0,015). No statistical difference was observed on the segmental kidney arteries (p=0,476). Dynamic Contrast enhanced ultrasound (CEUS) was done in B16F10, HCT-116 and MDA-MB-231 tumor xenografts, kidney and muscle tissues (n=3 per group). After HSS injection, relative blood volume was increased in B16F10 (p=0,022) and HCT-116 (p=0,039) but not on MDA-MB-231 (p=0,186). Changes on normal tissues were not statistically different (kidney p=0,957; muscle p=0,104). All statistical tests were two-sided. Administration of HSS as a vehicle for low molecular weight molecules cisplatin and doxorubicin in the treatment of B16F10 and 4T1 tumors respectively had no significant improvement of therapeutic efficacy, estimated by tumor growth and tumor weight measurements. Effect of HSS over retention of macromolecules in tumors SK-Mel-147 and 4T1, evaluated by epifluorescence imaging of the optical contrast IR- 783 was not large enough to reject the null hypothesis. HSS induces a transient increase in velocity of the blood as well as the blood volume that is relatively selective for the evaluated tumors with exception of MDA-MB-231. Data suggest that HSS administration might be a useful strategy to increase the delivery of molecules and optimize both therapy and diagnostic imaging
217

Homology-Based Functional Proteomics By Mass Spectrometry and Advanced Informatic Methods

Liska, Adam J. 16 December 2003 (has links)
Functional characterization of biochemically-isolated proteins is a central task in the biochemical and genetic description of the biology of cells and tissues. Protein identification by mass spectrometry consists of associating an isolated protein with a specific gene or protein sequence in silico, thus inferring its specific biochemical function based upon previous characterizations of that protein or a similar protein having that sequence identity. By performing this analysis on a large scale in conjunction with biochemical experiments, novel biological knowledge can be developed. The study presented here focuses on mass spectrometry-based proteomics of organisms with unsequenced genomes and corresponding developments in biological sequence database searching with mass spectrometry data. Conventional methods to identify proteins by mass spectrometry analysis have employed proteolytic digestion, fragmentation of resultant peptides, and the correlation of acquired tandem mass spectra with database sequences, relying upon exact matching algorithms; i.e. the analyzed peptide had to previously exist in a database in silico to be identified. One existing sequence-similarity protein identification method was applied (MS BLAST, Shevchenko 2001) and one alternative novel method was developed (MultiTag), for searching protein and EST databases, to enable the recognition of proteins that are generally unrecognizable by conventional softwares but share significant sequence similarity with database entries (~60-90%). These techniques and available database sequences enabled the characterization of the Xenopus laevis microtubule-associated proteome and the Dunaliella salina soluble salt-induced proteome, both organisms with unsequenced genomes and minimal database sequence resources. These sequence-similarity methods extended protein identification capabilities by more than two-fold compared to conventional methods, making existing methods virtually superfluous. The proteomics of Dunaliella salina demonstrated the utility of MS BLAST as an indispensable method for characterization of proteins in organisms with unsequenced genomes, and produced insight into Dunaliella?s inherent resilience to high salinity. The Xenopus study was the first proteomics project to simultaneously use all three central methods of representation for peptide tandem mass spectra for protein identification: sequence tags, amino acids sequences, and mass lists; and it is the largest proteomics study in Xenopus laevis yet completed, which indicated a potential relationship between the mitotic spindle of dividing cells and the protein synthesis machinery. At the beginning of these experiments, the identification of proteins was conceptualized as using ?conventional? versus ?sequence-similarity? techniques, but through the course of experiments, a conceptual shift in understanding occurred along with the techniques developed and employed to encompass variations in mass spectrometry instrumentation, alternative mass spectrum representation forms, and the complexities of database resources, producing a more systematic description and utilization of available resources for the characterization of proteomes by mass spectrometry and advanced informatic approaches. The experiments demonstrated that proteomics technologies are only as powerful in the field of biology as the biochemical experiments are precise and meaningful.
218

Natural and Anthropogenic Sources Controlling Regional Groundwater Geochemistry on the Niagara Peninsula

Smal, Caitlin January 2017 (has links)
Groundwater chemistry on the Niagara Peninsula has been identified as highly mineralized in comparison to groundwaters collected from the same bedrock formations elsewhere in southern Ontario. Three geochemical zones were discerned using hierarchical cluster analysis and other geochemical and isotopic methods. The Escarpment Zone, located along the Niagara and Onondaga Escarpments, is characterized by unconfined aquifer conditions, parameters reflective of surficial contaminants, including road salt, and elevated HCO3, DOC, NO3-, coliform bacteria and tritium. In contrast, in the Salina Zone thick, low-permeability sediments and gypsiferous bedrock results in highly mineralized groundwaters with Ca-SO4 geochemical facies and elevated S2-, Ca2+, Mg2+, K+, Na+, SO42-, Cl-, Br-, Sr2+, NH4+ and CH4. The Guelph Zone contains the lowest electrical conductivity of the three zones and elevated F-. Outliers exist with groundwater geochemistry that differs from the local geochemical zone and the host aquifer. These sites have elevated SO42- (>1000 to 5200 mg/L) with depleted δ34SSO4 (-2.2 to 14.3‰ VCDT) signatures that differs starkly from Devonian and Silurian evaporites (~20 to 32 ‰) in the host formations. This exogenic SO4 was identified in a cross-formational northeast – southwest linear trend crossing three major groundwater flow systems. The lack of down-stream impact in these systems and tritium groundwater ages that are typically only decades old indicate a young, non-geological origin and implicate anthropogenic activities. Additionally, nine samples were identified with elevated methane concentrations and δ13CCH4 signatures within the thermogenic range. As thermogenic methane is not produced within shallow aquifers and would be short-lived in the presence of the ubiquitous sulfate, these samples imply recent upward migration of methane from depth through vertical conduits. Taken together, the evidence supports large-scale upward movement of fluids in the centre of the Niagara geochemical anomaly and more sporadic upward transport of gases over a wider area of the peninsula. The most likely vector is through corroded and leaking casings or boreholes of abandoned (century) gas wells that are common across the peninsula. / Thesis / Master of Science (MSc)
219

Microalgae as novel ingredients for the formulation of food products

Uribe Wandurraga, Zaida Natalia 10 January 2021 (has links)
Tesis por compendio / [ES] Las microalgas son organismos unicelulares fotosintéticos microscópicos que se encuentran en gran variedad de ambientes y son muy eficientes en la transformación de energía solar en biomasa. Los estudios realizados hasta el momento hacen referencia a posibles beneficios de la incorporación de microalgas en la dieta, por la mejora del sistema cardiovascular, las propiedades adelgazantes y energizantes, capacidad antioxidante, o la reducción del colesterol y los triglicéridos. La forma más habitual de consumir las microalgas es como suplemento dietético en forma de tabletas, cápsulas o polvo. La incorporación de biomasa de microalgas en productos tradicionales se ha enfrentado al reto de la aparición de colores verdes fuertes, así como su consistencia pulverulenta que puede afectar la textura y percepción del producto. Todos estos aspectos constituyen las principales áreas de mejora para conseguir un mayor grado de aceptación de productos con microalgas, y son la base del reto de este proyecto. El objetivo de la presente tesis doctoral fue el desarrollo de nuevos productos alimentarios incorporando las propiedades nutricionales de la biomasa de microalgas, incrementando o mejorando con ello, las propiedades nutricionales del alimento original. Para conseguir este objetivo se evaluaron a nivel fisicoquímico, reológico y textural, la incorporación de diferentes especies de microalgas (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina y Nannochloropsis gaditana) en distintas matrices alimentarias (productos horneados, emulsiones y extrusionados). Por otra parte, se evaluó y caracterizó la incorporación de las microalgas utilizando diferentes tecnologías como la impresión 3D o la extrusión. Además de cómo afecta la incorporación de las microalgas a los productos obtenidos, se evaluaron los aspectos nutricionales de su incorporación, en cuanto al aporte de minerales y su biodisponibilidad. Las propiedades reológicas de las masas y emulsiones enriquecidas con microalgas (Spirulina, Chlorella y Dunaliella) indicaron que su comportamiento viscoelástico fue modificado y mejorado, mostrando características aptas para este tipo de productos. La adición de microalgas (Spirulina y Chlorella) a las masas utilizadas para la impresión 3D de galletas y snacks, permitió una mejor extrusión o impresión de éstas, obteniendo muestras impresas en 3D de forma cilíndrica, más precisas en cuanto a sus dimensiones con respecto a la estructura cilíndrica diseñada. Además, las muestras impresas presentaron mayor estabilidad y resistencia, antes y después del proceso de horneado comparadas con la muestra control. Para los productos horneados, tanto para las rosquilletas como los snacks impresos en 3D, la adición de microalgas (Spirulina y Chlorella) permitió mayor estabilidad en términos de textura. Ligeros cambios en los parámetros fisicoquímicos y de expansión se produjeron por la adición de Spirulina y Chlorella en los productos extrusionados. Además, los extrusionados enriquecidos con Nannochloropsis, mostraron parámetros similares a los de la muestra de control. Todos los productos presentaron colores luminosos y apariencias innovadoras y atractivas. En cuanto a los minerales, se observó un aumento de P, K, Ca, Na, Mg, Fe y Se con la adición de Spirulina y Chlorella, junto con el aumento de la concentración adicionada de microalgas. Siguiendo la normativa sobre etiquetado nutricional de los alimentos, el enriquecimiento con microalgas en rosquilletas se puede clasificar como un alimento "rico en hierro (Fe)". De igual forma, las rosquilletas y galletas enriquecidas con microalgas pueden considerarse un alimento "alto en selenio (Se)". Además, la incorporación de Spirulina y Chlorella en las formulaciones de galletas, permitió una mayor bioaccesibilidad del contenido de P, K, Ca, Mg, Fe, Zn y Se para la absorción en el cuerpo comparado con las muestras control. / [CAT] Les microalgues són organismes unicellulars fotosintètics microscòpics. Són molt eficients a l'hora de transformar l'energia solar en biomassa. Els estudis realitzats fins ara fan referència a possibles beneficis de la incorporació de microalgues en la dieta per produir una millora del sistema cardiovascular, per presentar propietats per aprimar i donar energia, per mostrar capacitat antioxidant o per afavorir una reducció del colesterol i els triglicèrids. La forma més habitual de consumir microalgues és com a suplement dietètic en forma de tauleta, càpsula o en pols. La incorporació de biomassa de microalgues en productes tradicionals s'ha afrontat al repte de l'aparició d'un color verd fosc i d'una consistència polsosa que pot afectar a la textura i, per tant, a la percepció del producte. Aquests aspectes constituïxen les principals àrees de millora per aconseguir un major grau d'acceptació de productes amb microalgues i són la base del repte d'aquest projecte. L'objectiu d'aquesta tesi doctoral és el desenvolupament de nous productes alimentaris que incorporen les propietats nutricionals de la biomassa de microalgues, de manera que s'incrementen o es milloren les propietats nutricionals de l'aliment original. Per aconseguir aquest objectiu s'avaluaren a escala fisicoquímica, reològica i de textura la incorporació de diferents espècies de microalgues (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina i Nannochloropsis gaditana) en diferents matrius alimentàries (productes fornejats, emulsions i extrudits). D'altra banda, s'avaluà i caracteritzà la incorporació de les microalgues utilitzant diferents tecnologies com la impressió en 3D o l'extrusió. A banda de valorar com afecta la incorporació de microalgues als productes elaborats, s'avaluaren els aspectes nutricionals, pel que fa a l'aportació i biodisponibilitat de minerals. Les propietats reològiques de les masses i emulsions enriquides amb microalgues (Spirulina, Chlorella i Dunaliella) indicaren que el seu comportament viscoelàstic fou modificat i millorat, de tal manera que mostrà característiques aptes per aquest tipus de productes. L'addició de microalgues (Spirulina i Chlorella) en les masses utilitzades per a la impressió 3D de galetes i snacks permeté una millor impressió, ja que s'obtingueren mostres impreses de forma cilíndrica amb unes dimensions més precises respecte a l'estructura cilíndrica dissenyada. A més, les mostres impreses presentaren una major estabilitat i resistència abans i després del procés de fornejat en comparació amb la mostra control. Respecte als productes fornejats, l'addició de microalgues (Spirulina i Chlorella) a les rosquilletes i els snacks impresos en 3D permeté una major estabilitat en termes de textura. Lleugers canvis als paràmetres fisicoquímics i d'expansió es produïren per l'addició d'Spirulina i Chlorella en els productes extrudits. A més, els extrudits que foren enriquits amb Nannochloropsis mostraren paràmetres similars als de la mostra control. Tots els productes presentaren colors lluminosos i aparences innovadores i atractives. Pel que fa als minerals, s'observà un augment de P, K, Ca, Na, Mg, Fe i Se quan s'afegí Spirulina i Chlorella, directament relacionat amb l'augment de la concentració de microalgues. Seguint la normativa sobre etiquetatge nutricional dels aliments, l'enriquiment amb microalgues en rosquilletes ens permet classificar-les com a aliment "ric en ferro (Fe)". De la mateixa manera, les rosquilletes i galetes enriquides amb microalgues poden considerar-se un aliment "alt en seleni (Se)". A més a més, la incorporació de Spirulina i Chlorella en les formulacions de galetes, permeté una major bioaccessibiltat del contingut de P, K, Ca, Mg, Fe, Zn i Se comparat amb les mostres control. / [EN] Microalgae are microscopic unicellular and photosynthetic organisms that can be found in a wide variety of environments. These microorganisms are very efficient when transforming solar energy into biomass, due to their cellular structure, which is completely submerged in an aqueous medium, forming an adequate surface for the exchange of nutrients and gases. Microalgae compounds are now known to exhibit cardioprotective, immunomodulatory, anti-proliferative, anti-inflammatory, cognitive, neurobehavioral and antimicrobial properties, amongst others. Researchers have shown possible benefits of the incorporation of microalgae in the diet so far. The most common way to consume microalgae is as a dietary supplement in the form of tablets, capsules or powder. The incorporation of microalgae biomass in traditional products has faced the challenge of the appearance of strong green colours, as well as its powdery consistency that can affect the texture and perception of the product. All these aspects constitute the main areas for improvement the development of microalgae-based products, and they are the challenges faced of this project. The main objective of this PhD Thesis was the development of novel food products incorporating the nutritional properties of microalgae biomass, thereby increasing or improving the nutritional properties of the original food matrix. To achieve this goal, the effect of the addition of different species of microalgae (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina and Nannochloropsis gaditana) on the physicochemical, rheological and textural properties of different food matrices (baked products, emulsions and extrudates) was evaluated. Furthermore, the effect of the incorporation of microalgae using different technologies such as 3D printing or extrusion to obtain food products was studied. In addition, how the incorporation of microalgae affects the nutritional aspects of the food products in terms of the contribution of minerals and their bioavailability was also evaluated. The rheological properties of doughs, batters and emulsions enriched with microalgae (Spirulina, Chlorella and Dunaliella) indicated that their viscoelastic behaviour was modified and improved, showing characteristics suitable for this type of products. The addition of microalgae (Spirulina and Chlorella) to the doughs and batters used for the 3D printing of cookies and snacks, allowed a better extrusion or printing behaviour. This allowed obtaining cylindrical 3D printed samples, more precise in terms of their dimensions with respect to the designed cylindrical structure. In addition, the 3D microalgae-printed sample structures presented greater stability and resistance, before and after the baking process compared to the control sample. For baked products, both for breadsticks and 3D printed snacks, the addition of microalgae (Spirulina and Chlorella) allowed greater stability in terms of texture. Slight changes in the physicochemical and expansion parameters were produced by the addition of Spirulina and Chlorella in the extruded products. In addition, the extrudates enriched with Nannochloropsis, showed similar parameters to those of the control sample. Microalgae-enriched obtained products showed bright colours with appealing appearances. Regarding minerals, an increase in P, K, Ca, Na, Mg, Fe and Se was observed with the addition of Spirulina and Chlorella, along the increase of concentration of microalgae addition. Following the regulations on nutrition labelling for food stuffs, breadstick enrichment with microalgae are a food "high in iron (Fe)" In the same way, breadsticks and cookies enriched with microalgae can be considered a "high in selenium (Se)" food. Going a step further, Spirulina and Chlorella vulgaris incorporation in cookie formulations allowed for greater bioaccessibility of P, K, Ca, Mg, Fe, Zn, and Se content for absorption in the body than control cookies. / Uribe Wandurraga, ZN. (2020). Microalgae as novel ingredients for the formulation of food products [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/158743 / Compendio

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