605 resultados para Anaphoric Encapsulation


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International audience

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Além de ser o cogumelo mais consumido no mundo, Agaricus bisporus é um dos cogumelos mais ricos em ergosterol, representando esta molécula quase 90% da sua fração de esteróis. Vários estudos têm atribuído ao ergosterol diferentes bioatividades, incluindo efeitos hipocolesterolémicos semelhantes aos exibidos pelos fitoesteróis. Isto torna o ergosterol uma molécula interessante para ser estudada como composto nutracêutico. Assim, este trabalho teve como objetivo avaliar o potencial de utilização dos extratos de A. bisporus ricos em ergosterol na produção de bebidas lácteas funcionais. Para o efeito, foram realizados testes de incorporação do extrato e do ergosterol puro em iogurtes que se compararam com bebidas lácteas funcionais comerciais (aditivadas com fitoesteróis). As amostras de A. bisporus foram submetidas a uma extração assistida por ultrassons e os extratos obtidos (IEXT), bem como a molécula de ergosterol em diferentes concentrações (IERG1 e IERG2), foram incorporados em iogurtes, e comparadas com amostras controlo (amostras de iogurte sem aditivos) (ICN) e iogurtes comerciais contendo fitoesteróis (ICP). Todas as amostras foram analisadas imediatamente após a incorporação (T0), e após sete dias de armazenagem a 4°C (T1), em relação aos parâmetros nutricionais, atividade antioxidante e propriedades citotóxicas em linhas celulares tumorais humanas e numa cultura primária de células de fígado de porco (não tumoral) para avaliação da toxicidade. O teor de ergosterol incorporado na forma pura, ou presente nos extratos, foi monitorizado por HPLC-UV. Adicionalmente, foi realizado um estudo de microencapsulação utilizando a técnica de coacervação, tendo o quitosano e o isolado proteico de soro como materiais encapsulantes. Num ensaio preliminar determinou-se o pH conducente a um maior rendimento de encapsulação e, seguidamente, verificou-se a influência da razão proteína:quitosano (P/Q) e da temperatura utilizada, no rendimento de encapsulação (Y1), na eficiência de encapsulação (Y2) e na carga (teor de ergosterol nas microesferas) (Y3). Posteriormente, o estudo foi realizado baseando-se nas melhores condições para encapsular ergosterol, sendo também avaliadas as respostas Y1, Y2 e Y3. Além de ser o cogumelo mais consumido no mundo, Agaricus bisporus é um dos cogumelos mais ricos em ergosterol, representando esta molécula quase 90% da sua fração de esteróis. Vários estudos têm atribuído ao ergosterol diferentes bioatividades, incluindo efeitos hipocolesterolémicos semelhantes aos exibidos pelos fitoesteróis. Isto torna o ergosterol uma molécula interessante para ser estudada como composto nutracêutico. Assim, este trabalho teve como objetivo avaliar o potencial de utilização dos extratos de A. bisporus ricos em ergosterol na produção de bebidas lácteas funcionais. Para o efeito, foram realizados testes de incorporação do extrato e do ergosterol puro em iogurtes que se compararam com bebidas lácteas funcionais comerciais (aditivadas com fitoesteróis). As amostras de A. bisporus foram submetidas a uma extração assistida por ultrassons e os extratos obtidos (IEXT), bem como a molécula de ergosterol em diferentes concentrações (IERG1 e IERG2), foram incorporados em iogurtes, e comparadas com amostras controlo (amostras de iogurte sem aditivos) (ICN) e iogurtes comerciais contendo fitoesteróis (ICP). Todas as amostras foram analisadas imediatamente após a incorporação (T0), e após sete dias de armazenagem a 4°C (T1), em relação aos parâmetros nutricionais, atividade antioxidante e propriedades citotóxicas em linhas celulares tumorais humanas e numa cultura primária de células de fígado de porco (não tumoral) para avaliação da toxicidade. O teor de ergosterol incorporado na forma pura, ou presente nos extratos, foi monitorizado por HPLC-UV. Adicionalmente, foi realizado um estudo de microencapsulação utilizando a técnica de coacervação, tendo o quitosano e o isolado proteico de soro como materiais encapsulantes. Num ensaio preliminar determinou-se o pH conducente a um maior rendimento de encapsulação e, seguidamente, verificou-se a influência da razão proteína:quitosano (P/Q) e da temperatura utilizada, no rendimento de encapsulação (Y1), na eficiência de encapsulação (Y2) e na carga (teor de ergosterol nas microesferas) (Y3). Posteriormente, o estudo foi realizado baseando-se nas melhores condições para encapsular ergosterol, sendo também avaliadas as respostas Y1, Y2 e Y3. As bebidas funcionalizadas com o extrato (IEXT) e com ergosterol na mesma concentração existente no extrato (IERG1) revelaram uma atividade antioxidante similar às bebidas comerciais com fitoesteróis. No entanto, as bebidas com ergosterol na mesma concentração do extrato de A. bisporus e de fitoesteróis (IERG2) revelaram uma atividade antioxidante superior. Além disso, apenas IEXT, IERG1 e IERG2 apresentaram um aumento na atividade antioxidante de T0 para T1, com destaque para a atividade exibida por IERG2, significando que o ergosterol e os extratos foram capazes de proteger a bebida láctea da oxidação, aumentando a vida de prateleira do produto. IERG2 foi a amostra que revelou a maior citotoxicidade para as linhas celulares tumorais, enquanto as bebidas com fitoesteróis mostraram a menor atividade, sem diferenças significativas entre T0 e T1. Os estudos de microencapsulação revelaram ainda que a técnica de coacervação permite obter cápsulas de distintos tamanhos e que as condições ótimas do processo ocorrem a pH 5,5, com temperatura de 55ºC e razão P/Q de 0,5, com um menor rendimento de encapsulação, mas com uma maior carga em ergosterol. Este trabalho contribuiu para o estudo do potencial da utilização de extratos de A. bisporus com ergosterol no desenvolvimento de novas bebidas funcionais. Constituiu um primeiro passo que necessita de estudos subsequentes relacionados com a avaliação da viabilidade da sua utilização ao nível industrial e demonstração clara da sua bioatividade in vivo.

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The use of antibiotics in aquaculture has been limited. Scientifics seeking for natural substitutes to prevent of aquatic animals diseases. Considering seaweeds are rich of nutritions and bioactive compounds, the purpose of this study is: investigation the potential and use possibility of native seaweeds from Persian Gulf in shrimp aquculture industry to improve growth, survival of postlarvae and to resistance against pathogens such as vibriosis. For this propose 7 macroalgae species from Bushehr province coast, inclouding: green algae (C. iyengarii), brown algae (S. angutifolium and S. ilicifolium) and red algae (L. snyderiae, K. alvarezii and G. corticata) were collected and identified. Then seaweed extracts abtained by Water, Ethanol, Methanol and Chloroform solvents by soaking method. In vitro antibacterial activity of extracts against Gr+ bacteria (S. aureus and B. subtilis) and Gr- bacteria (V. harveyi, V. alginolyticus and E. coli) was conducted by Agar diffusion, MIC and MBC methods. Antioxidant activity also by DPPH and EC50 methods was investigated. According to results of these two tests four seaweeds species (S. angutifolium, L. snyderiae, K. alvarezii and G. corticata) were selected for use in shrimp postlarvae (PL22) diets by Bio-Encapsulation (Artemia enrichment). Before of enrichment, toxicity effect of extracts to Artemia nauplii were evaluated by determination of LC50 24 h method. From results of this section Ethanol extracts were selected to bioencapsulation. After encapsulation shrimp postlarvae divided to 12 groups in triplicate, namely: C-, C+, S (200), S (400), S (600), L(200), L(400), L(600), G(300), G(600), K(300) and K(600). During 30 days of reared period C- and C+ use of basal diet and unenriched Artemia, but the other groups use of basal diet and enriched Artemia. Except C-, the shrimps in first day of culture put in 107 cfu/ml v. harveyi suspension for 30 minutes, and after water exchange 10 ml of this dose was added to reared aquaria. After 30 days survival percentage, obtained weight and SGR% were investigated. To evaluate vibrio loading, every 10 days 5 postlarvae were sampled randomly for vibrio count. Results showed that vibrio count in C- was less than the others and in C+ was more than the others. In treatments vibrio count in L(200) was the most and L(600) was the less. Survival rate in C- was the most and after that G(600) with 79.4±6.6% and then S(300) and K(600) were 73.3±7.3% and 70.6±6.6% respectively that were significantly compare the other (P < 0.01). Also the C+ was the less with 33.3±6.6% that difference was significant (P< 0.01). In this study growth parameters of all groups that fed by enriched Artemia were better than C+ (P<0.05). After cultre period 10 shrimp of every aquarium disinfected and reared for 10 days like before treatment. After 10 days the shrimps were challenged by 3×108 cfu/ml V. harveyi and mortality was recorded for 7 days. The all of animals in C- were survive but more than 90% of C+ were dead. And survival in all of treatments were better the C+ (P<0.05). The study showed the ethanol extracts of selected seaweed from Persian Gulf is a good source for growth, Survival and disease control in shrimp larviculture.

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Dissertação de mestrado em Bioquímica, apresentada à Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, 2016.

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Currently, many consumers search for food with functional characteristics beyond their nutritional properties. Thus, the concept of functional food becomes a hot topic, allowing the obtaining of health benefits, including disease prevention. In this context, plants are recognized as sources of a wide range of bioactives, mainly phenolic compounds. In particular, the Rosmarinus officina/is L., commonly referred as rosemary, has several phenolic compounds with different bioactive properties such as antioxidant, antiinflammatory and antimicrobial activities, among others [!]. Hence, this plant has great potential for incorporation into foods in order to confer bioactivity to the final products. However, it should be highlighted that the bioactive compounds if exposed to adverse environments, for example: light, moisture, extreme pH, storage, food processing conditions, can be degraded leading to the consequent loss of bioactivity [2]. The microencapsulation is an alternative to overcome this problematic of bioactive compounds, as also to ensure controlled release, or target deliver to a specific site [3]. In this work, lyophilized rosemary aqueous extract prepared by in:'usion was used as a functional ingredient for cottage cheeses, after proving that it possesses, both higher content in phenolic compounds and higher antioxidant activity, comparatively with the corresponding hydroethanolic extract. The rosemary aqueous extract revealed, for example, a DPPH scavenging activity with an EC50 value of 73.44±0.54j!g/mL and presented as main phenolic compound the caffeic acid dimer, commonly named as rosmarinic acid. For the functionalized cottage cheeses, a decrease of bioactivity was observed after seven days under storage in fridge, when the extracts were incorporated in its free form. Therefore, to preserve the antioxidant activity, the rosemary aqueous extract was efficiently microencapsulated by using an atomization/coagulation technique and alginate as the matrix material and thereafter incorporated into the cottage cheeses. The final microspheres showed a size, estimated by OM using a magnification of I OOx, ranging between 51.1 and 122.6 J!m and an encapsulation efficiency, estimated through an indirect method, approaching 100%. Overall, the introduction of both free and microencapsulated extracts did not change the nutritional value of cottage cheeses, providing bioactivity that was more preserved with microencapsulated extracts putting in evidence the importance of using microencapsulation to develop effective functional foods.

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Foeniculum vulgare Mill. (fennel) and Matricaria recutita L. (chamomile) are two examples of plants with reported antioxidant and antimicrobial properties, which can be related with their composition in phenolic compounds [1,2]. Furthermore, according to previous results of our research group, the direct incorporation of the aqueous extracts showed capacity to maintain the nutritional properties of the cottage cheeses, up to 7 days of storage, while improving the antioxidant potential. However, after 14 days, a decrease in the antioxidant properties was observed [1,2], which can be related with factors such as light, moisture, temperature and pH, that can cause bioactive compounds degradation. Therefore, the aim of the present study was to prepare microcapsules with the aqueous extracts of fennel and chamomile for incorporation in cottage cheese samples, in order to protect the bioactive molecules present in the extracts, such as phenolic compounds, and prevent the decrease of the antioxidant activity observed after the 14 days period. The microspheres were prepared using an atomization/coagulation technique. Sodium alginate was used as the matrix material to produce the microspheres that were characterized through optical microscopy (OM), during and after atomization, for inspecting morphology. The encapsulation efficiency (EE) was determined by HPLC-DAD by an indirect method by analysing the coagulation solution. FTIR was also used to attest the presence of the extract inside of the alginate matrix. These microencapsulated extracts were incorporated in cottage cheese samples that were further characterized in terms of nutritional properties and antioxidant potential right after incorporation, and after 7 and 14 days of storage at 4•c. The EE was estimated as -100% and the FTIR analysis confirmed the presence of the extracts inside the microspheres. The results showed that the incorporation of the microencapsulated extracts did not cause changes in the nutritional value of cottage cheeses (through a comparison with control samples without extracts). The predominant fatty acids were palmitic (C16:0) and oleic (CI8:0) acids. The order of abundance of fatty acids was as follows: saturated fatty acids (SF A)> monounsaturatcd fatty acids (MUF A)> polyunsaturated fatty acids (PUF A). Regarding free sugars, lactose was the only sugar identified and quantified in all samples. Regarding the antioxidant activity, the samples functionalized with the microencapsulated extracts showed a higher preservation of this property even after the 7th day of storage. Overall, the incorporation of the protected plant extracts in dairy foods can be a strategy to provide health benefits to consumers.

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Maintaining accessibility to and understanding of digital information over time is a complex challenge that often requires contributions and interventions from a variety of individuals and organizations. The processes of preservation planning and evaluation are fundamentally implicit and share similar complexity. Both demand comprehensive knowledge and understanding of every aspect of to-be-preserved content and the contexts within which preservation is undertaken. Consequently, means are required for the identification, documentation and association of those properties of data, representation and management mechanisms that in combination lend value, facilitate interaction and influence the preservation process. These properties may be almost limitless in terms of diversity, but are integral to the establishment of classes of risk exposure, and the planning and deployment of appropriate preservation strategies. We explore several research objectives within the course of this thesis. Our main objective is the conception of an ontology for risk management of digital collections. Incorporated within this are our aims to survey the contexts within which preservation has been undertaken successfully, the development of an appropriate methodology for risk management, the evaluation of existing preservation evaluation approaches and metrics, the structuring of best practice knowledge and lastly the demonstration of a range of tools that utilise our findings. We describe a mixed methodology that uses interview and survey, extensive content analysis, practical case study and iterative software and ontology development. We build on a robust foundation, the development of the Digital Repository Audit Method Based on Risk Assessment. We summarise the extent of the challenge facing the digital preservation community (and by extension users and creators of digital materials from many disciplines and operational contexts) and present the case for a comprehensive and extensible knowledge base of best practice. These challenges are manifested in the scale of data growth, the increasing complexity and the increasing onus on communities with no formal training to offer assurances of data management and sustainability. These collectively imply a challenge that demands an intuitive and adaptable means of evaluating digital preservation efforts. The need for individuals and organisations to validate the legitimacy of their own efforts is particularly prioritised. We introduce our approach, based on risk management. Risk is an expression of the likelihood of a negative outcome, and an expression of the impact of such an occurrence. We describe how risk management may be considered synonymous with preservation activity, a persistent effort to negate the dangers posed to information availability, usability and sustainability. Risk can be characterised according to associated goals, activities, responsibilities and policies in terms of both their manifestation and mitigation. They have the capacity to be deconstructed into their atomic units and responsibility for their resolution delegated appropriately. We continue to describe how the manifestation of risks typically spans an entire organisational environment, and as the focus of our analysis risk safeguards against omissions that may occur when pursuing functional, departmental or role-based assessment. We discuss the importance of relating risk-factors, through the risks themselves or associated system elements. To do so will yield the preservation best-practice knowledge base that is conspicuously lacking within the international digital preservation community. We present as research outcomes an encapsulation of preservation practice (and explicitly defined best practice) as a series of case studies, in turn distilled into atomic, related information elements. We conduct our analyses in the formal evaluation of memory institutions in the UK, US and continental Europe. Furthermore we showcase a series of applications that use the fruits of this research as their intellectual foundation. Finally we document our results in a range of technical reports and conference and journal articles. We present evidence of preservation approaches and infrastructures from a series of case studies conducted in a range of international preservation environments. We then aggregate this into a linked data structure entitled PORRO, an ontology relating preservation repository, object and risk characteristics, intended to support preservation decision making and evaluation. The methodology leading to this ontology is outlined, and lessons are exposed by revisiting legacy studies and exposing the resource and associated applications to evaluation by the digital preservation community.

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This study reports an investigation of the pharmacological activity, cytotoxicity, and local effects of a liposomal formulation of the novel local anaesthetic ropivacaine (RVC) compared with its plain solution. RVC was encapsulated into large unilamellar vesicles (LUVs) composed of egg phosphatidylcholine, cholesterol and a-tocopherol (4:3:0.07, mole %). Particle size, partition coefficient determination and in-vitro release studies were used to characterize the encapsulation process. Cytotoxicity was evaluated by the tetrazolium reduction test using sciatic nerve Schwann cells in culture. Local anaesthetic activity was assessed by mouse sciatic and rat infraorbital nerve blockades. Histological analysis was performed to verify the myotoxic effects evoked by RVC formulations. Plain (RVCPLAIN) and liposomal RVC (RVCLUV) samples were tested at 0.125%, 0.25% and 0.5% concentrations. Vesicle size distribution showed liposomal populations of 370 and 130 nm (85 and 15%, respectively), without changes after RVC encapsulation. The partition coefficient value was 132 26 and in-vitro release assays revealed a decrease in RVC release rate (1.5 fold, P < 0.001) from liposomes. RVCLUV presented reduced cytotoxicity (P < 0.001) when compared with RVCPLAIN Treatment with RVCLUV increased the duration (P < 0.001) and intensity of the analgesic effects either on sciatic nerve blockade (1.4-1.6 fold) and infraorbital nerve blockade tests (1.5 fold), in relation to RVCPLAIN. Regarding histological analysis, no morphological tissue changes were detected in the area of injection and sparse inflammatory cells were observed in only one of the animals treated with RVCPLAIN or RVCLUV at 0.5%. Despite the differences between these preclinical studies and clinical conditions, we suggest RVCLUV as a potential new formulation, since RVC is a new and safe local anaesthetic agent.

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Dissertação (mestrado)–Universidade de Brasília, Universidade UnB de Planaltina, Programa de Pós-Graduação em Ciência de Materiais, 2015.

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Dissertação de Mestrado, Tecnologia de Alimentos, Instituto Superior de Engenharia, Universidade do Algarve, 2016

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Purpose: To evaluate the efficacy and safety of methotrexate (MTX) nanoparticles in pediatric patients with inflammatory bowel disease (IBD). Methods: In this randomized, open-label clinical study, 28 pediatric patients with moderate to severe IBD were randomly assigned to treatment (MTX nanoparticles,15 mg/week) or control (azathioprine, AZA, 2 mg/kg/day) group. Nanoparticles were synthesized by adding calcium chloride to sodium alginate solution containing MTX, and was further treated with poly-L-lysine aqueous solution. The nanoparticles were evaluated for particle size, zeta potential and drug encapsulation efficacy. Erythrocyte sedimentation rate, C-reactive protein, aspartate aminotransferase, alanine transaminase, and disease activity scores were used to assess IBD remission. Results: Nanoparticle size, zeta potential and encapsulation efficacy were 164.4 ± 6.9 nm, -32.6 ± 3.7 mV, and 97.8 ± 4.2 %, respectively. After 12 weeks of therapy, the mean Pediatric Crohn\'s Disease Activity Index (PCDAI) scores for control and treatment groups were 22.3 ± 2.14 and 16.8 ± 1.87, respectively, while mean Pediatric Ulcerative Colitis Activity (PUCAI) Index scores were 24.3 ± 1.47 and 18.7 ± 1.92, respectively. Eight patients in the treatment and five patients in the control group achieved remission. Biochemical parameters varied significantly between the groups. Conclusion: MTX nanoparticles are safe and more effective than standard first-line IBD therapy. However, further studies are required to determine the suitability of the formulation for therapeutic use.

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Tese (doutorado)—Universidade de Brasília, Instituto de Química, Curso de Pós-Graduação em Química, 2016.

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With the exponential growth of the usage of web-based map services, the web GIS application has become more and more popular. Spatial data index, search, analysis, visualization and the resource management of such services are becoming increasingly important to deliver user-desired Quality of Service. First, spatial indexing is typically time-consuming and is not available to end-users. To address this, we introduce TerraFly sksOpen, an open-sourced an Online Indexing and Querying System for Big Geospatial Data. Integrated with the TerraFly Geospatial database [1-9], sksOpen is an efficient indexing and query engine for processing Top-k Spatial Boolean Queries. Further, we provide ergonomic visualization of query results on interactive maps to facilitate the user’s data analysis. Second, due to the highly complex and dynamic nature of GIS systems, it is quite challenging for the end users to quickly understand and analyze the spatial data, and to efficiently share their own data and analysis results with others. Built on the TerraFly Geo spatial database, TerraFly GeoCloud is an extra layer running upon the TerraFly map and can efficiently support many different visualization functions and spatial data analysis models. Furthermore, users can create unique URLs to visualize and share the analysis results. TerraFly GeoCloud also enables the MapQL technology to customize map visualization using SQL-like statements [10]. Third, map systems often serve dynamic web workloads and involve multiple CPU and I/O intensive tiers, which make it challenging to meet the response time targets of map requests while using the resources efficiently. Virtualization facilitates the deployment of web map services and improves their resource utilization through encapsulation and consolidation. Autonomic resource management allows resources to be automatically provisioned to a map service and its internal tiers on demand. v-TerraFly are techniques to predict the demand of map workloads online and optimize resource allocations, considering both response time and data freshness as the QoS target. The proposed v-TerraFly system is prototyped on TerraFly, a production web map service, and evaluated using real TerraFly workloads. The results show that v-TerraFly can accurately predict the workload demands: 18.91% more accurate; and efficiently allocate resources to meet the QoS target: improves the QoS by 26.19% and saves resource usages by 20.83% compared to traditional peak load-based resource allocation.