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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.
201

Die rheumatoide Arthritis

Hermann, Kay-Geert 13 November 2000 (has links)
Multimedia - Wort des Jahres 1995 - taucht als populärer Begriff in allen Bereichen unserer Gesellschaft auf. Auch an Universitäten erhofft man sich durch die Einführung von computerunterstützten Lernformen eine höhere Qualität der Lehre sowie Kosteneinsparungen. Nach ersten Versuchen in den 60er Jahren war das Neue in den 90ern die realitätsnahe, multimediale Simulation von Entscheidungssituationen. Auf dem Gebiet der Rheumatologie ist derzeit jedoch noch ein Mangel an deutschsprachigen Softwaretiteln zu erkennen. Ziel war die Erstellung eines multimedialen Kompendiums über die rheumatoide Arthritis für den Einsatz in der universitären und postgraduierten Lehre. Das System soll als elektronisches Nachschlagewerk und als Basis für interaktive Diashows geeignet sein. Mit Hilfe eines Apple Macintosh und der Autorensoftware Macromedia Director wurde eine CD-ROM entwickelt, die sowohl für Macintosh- als auch für Windows-Computer geeignet ist. Die Beschreibung der Symptome der rheumatoiden Arthritis und der erforderlichen Untersuchungstechniken nimmt mit 31% der Bildschirmseiten den größten Teil des vorliegenden Multimedia-Kompendiums ein. Weitere Schwerpunkte wurden auf Pathogenese (19%), bildgebende Verfahren (14%), Differentialdiagnosen (11%), Therapie (10%) und Laboruntersuchungen (7%) gelegt. Videos und Animationen dienen der Illustration zellulärer Vorgänge und der Zusammenfassung klinischer Untersuchungstechniken. Etablierte Kriterienkataloge für elektronische Medien dienten der Qualitätssicherung im Entwicklungsprozeß. Eine parallel durchgeführte formative Evaluation lieferte erste Erkenntnisse über Praxistauglichkeit und Stabilität des Programmes, ohne jedoch eine fundierte summative Evaluation ersetzen zu können. Multimedia-Lehrbücher wie das vorliegende Kompendium stellen für den konventionellen Unterricht eine ideale Ergänzung zum klassischen Lehrbuch dar und dienen für die problemorientierte Ausbildung als schnell zur Verfügung stehende Wissensbasis. Jedoch blieben bei der fakultativen Nutzung von computerbasierten Lernmöglichkeiten in Lernzentren die Ergebnisse bisher hinter den Erwartungen zurück. Es ist zu diskutieren, inwieweit die Vorteile der Multimedia-Technologie durch gezielte Integration in das Curriculum an deutschen Hochschulen zu Kosten- und Zeitersparnissen führen können. / Multimedia - word of the year 1995 in Germany - is a popular term cropping up in all areas of society. Universities, too, hope to improve the quality of teaching and to cut costs by introducing computer-based forms of learning. Following initial attempts in the sixties, a new aspect introduced in the nineties was the life-like multimedia simulation of decision-making situations. In medicine, there still is a lack of German-language software packages in rheumatology. The aim of the present project was to develop a multimedia compendium on rheumatoid arthritis for teaching at the university and postgraduate level. The system was intended to serve both as an electronic work of reference and as a basis for interactive slide presentations. Using the authoring tool Macromedia Director on an Apple Macintosh computer, a CD-ROM was developed that can be run on Macintosh and Windows computers alike. The largest part of the multimedia compendium now available (31% of the screen pages) is dedicated to the description of the symptoms of rheumatoid arthritis and examination techniques. Other main areas are pathogenesis (19%), imaging modalities (14%), differential diagnoses (11%), therapy (10%), and laboratory tests (7%). Videos and animations serve to illustrate cellular processes and to summarize the clinical examination techniques. Catalogues of established criteria for electronic media were adhered to during development to assure quality. A simultaneously performed formative evaluation yielded initial results about the practicability and stability of the program but cannot replace a thorough summative evaluation. Multimedia textbooks such as the compendium presented here are ideal supplements to classical textbooks in conventional teaching, providing a rapidly accessible knowledge base for problem-oriented training. However, the results achieved with computer-based learning tools available for optional use at teaching centers have so far lagged behind expectations. It remains to be discussed to what extent the advantages of multimedia technology can save both cost and time by being selectively integrated into the curriculum at German universities.
202

Piratkopiering - en oändlig historia?

Akermark, Adam, Svensson, Martin January 2006 (has links)
<p>Abstrakt (svenska)</p><p>Bakgrund: Piratkopieringen bara ökar och ökar. Program-, spel- och musikbranschen har idag stora problem. En i stort sett okunnig användare kan fixa en nyutgiven skiva innan den nått butikerna på grund av piratkopieringen. Detta problem möjliggörs genom att ingen bra lösning finns i form av fungerande kopieringsskydd samt att fildelningstjänsterna får stort spelrum. Vi går in specifikt och undersöker musikbranschen.</p><p>Syfte: Fördjupa oss i begreppet piratkopiering. Vidare vill vi upplysa och informera såväl musikbranschen som användare om problemet och dess framtid. Vi hoppas att det resultat vi kommer fram till kan ge underlag för vidare forskning.</p><p>Metod: Vår information har tagits från artiklar på Internet samt från litteratur vi ansett vara aktuell. Telefonintervjuer har skett med Magnus Mårtensson, IFPI (International Federation of the Phonographic Industry), programjuristen Anna Burén på Sveriges Radio, Per Sandin,</p><p>General manager EMI marketing samt ett flertal Internetleverantörer. Vi har dessutom sammanställt en enkät som besvarats av en mängd personer.</p><p>Resultat: Många av gårdagens skivköpare anser att priset för en CD-skiva är för dyrt idag. Man har upptäckt piratkopieringen med dess obegränsade funktioner samt insett hur lätt det är att få tag på gratis musik utan repressalier, vilket beror på den idag vaga och ej alltför avskräckande lagstiftningen. Musikbolagen förlorar pengar och höjer därmed priserna för skivorna samtidigt som de aktivt arbetar för att hitta det perfekta kopieringsskyddet eller för att komma på någon annan strålande lösning. Framtiden ser oviss ut och för tillfället har</p><p>piratkopierarna och fildelningstjänsterna trumf på hand.</p><p>Nyckelord: Mp3, CD, Kopieringsskydd, Fildelningstjänster, Upphovsrätt och Musikintressenter.</p> / <p>Abstract (English)</p><p>Background: Illegal copying increases rapidly. Software-, game- and music industry are experiencing troubled times at the moment. Today, a practically ignorant person would have no problems to get hold of a newly published record before it reaches the stores because of the</p><p>illegal copying. This problem is made possible due to that no good solution exists. Copy protection isn’t good enough and peer-to-peer-networks are bigger than ever. In this work we will examine specifically the music industry.</p><p>Purpose: We will specialize in the term of illegal copying. Further we want to enlight and inform the music industry as well as the users of the problem and it´s future. We hope the result we will achieve can be a foundation for further research.</p><p>Realization: We have gathered our information from articles on the Internet and also from updated literature. Interviews were made over the phone with Magnus Mårtensson, IFPI (International Federation of the Phonographic Industry), Anna Burén, lawyer of copyright at</p><p>Swedish Radio, Per Sandin, General manager EMI marketing and also a lot of Internetsuppliers. We have also compilated an inquiry which has been replied to by many people.</p><p>Conclusion: Many of the buyers from the past consider the cost of a CD far too high. Instead they have discovered the illegal copying and its unlimited functions. They have also realized how easy you can get new music without reprisals, which mostly depends on the vague and</p><p>not to scary laws. Music companies are losing money and therefore they raise the prize of a single CD, simultaneously as they work to find the perfect copy protection. The future looks uncertain and for the moment, those who are copying along with peer-to-peer-networks have</p><p>all the trumps.</p><p>Keywords: mp3, CD, copy-protection, peer-to-peer-networks, copyright, illegal copying, music companies.</p>
203

Mokomasis CD pradinukui: tipinių veiklos scenarijų realizavimas / Educational CD for Primary Learners: Implementation of Typical Learning Scenarios

Tyliutė, Laima 27 August 2009 (has links)
Mokomasis CD tipiniai veiklos scenarijai sukurti remiantis pakartotino panaudojimo koncepcija. Teorinėje dalyje atlikta mokomųjų CD, naudojamų ugdymo procese, analizė, aiškintasi pakartotino panaudojimo koncepcija, susipažinta su šablonais – komponentais ir jų taikymu MO (mokymo objektuose). Praktinėje dalyje aprašomas sukurtas mokomasis CD ir jo komponentai, veikimo principas, pateikiami testavimo rezultatai. Šis darbas parengtas naudojantis Adobe Flash CS 3 technologijas, naudojant Action Script 2. / Educational CD with action script realization was created on the basis of re-creating the concept of recovery. Theoretical part of this work includes the analysis of the CD use in teaching and educational processes. It also includes the analysis of the concept of re-use and getting familiar with the pattern of the application of TO (teaching objects). The practical part of the work describes the developed educational CD and its components, operating principle and the test results. This work is based on Adobe Flash CS 3 technology, using Action Script 2.
204

Défis liés à la réduction de la rugosité des motifs de résine photosensible 193 nm

Azar-nouche, Laurent 04 July 2012 (has links) (PDF)
A chaque nouvelle étape franchie dans la réduction des dimensions des dispositifs en microélectronique, de nouvelles problématiques sont soulevées. Parmi elles, la fluctuation de la longueur de la grille des transistors, aussi appelée rugosité de bord de ligne (LWR, pour "Line Width Roughness"), constitue l'une des principales sources de variabilité. Afin d'assurer le bon fonctionnement des transistors, le LWR doit être inférieur à 2 nm pour les futurs noeuds technologiques. Dans ce contexte, la caractérisation précise de la rugosité à l'échelle nanométrique est essentielle mais se heurte aux limitations des équipements de métrologie. En effet, à ces dimensions, le bruit de mesure des équipements ne peut être ignoré. Afin de pallier à ce problème, un protocole permettant de s'affranchir du niveau de bruit des équipements de métrologie a été développé dans la première partie de cette thèse. Il s'appuie sur l'utilisation de la densité spectrale de puissance de la rugosité, basée sur une fonction d'autocorrélation de type "fractal auto-affine". Un bruit "blanc" a été inclus dans le modèle théorique, permettant l'ajustement des données expérimentales. La seconde problématique concerne la rugosité élevée des motifs des résines 193 nm qui est transférée dans la grille lors des étapes successives de gravure. Pour résoudre cette difficulté, des traitements plasma sur résines ont été envisagés dans la seconde partie de cette étude. Des analyses physico-chimiques des résines exposées aux traitements plasma nous ont permis de montrer que les UV émis par les plasmas lissent considérablement les flancs des résines. En contrepartie, la formation d'une couche "dure" autour des motifs avec certains plasmas (HBr et Ar) contribue à leur dégradation. De nouvelles stratégies ont également été examinées. Les traitements plasma ont été combinés à des recuits thermiques dans le but d'additionner leurs avantages. Finalement, un plasma de H2 semble être prometteur puisqu'il ne génère pas de couche superficielle sur les motifs de résine, et l'action des UV réduit considérablement la rugosité. En combinant ce traitement avec un recuit thermique, il est possible d'atteindre des rugosités de 2.4 nm dans la grille finale.
205

光碟產業的競爭策略-以A公司為例 / The Competitive Strategy of Optical Storage Disc Industry-- A Case Study of A Company

閻正雄, Yen,cheng hsiung Unknown Date (has links)
光電產業一直是政府積極輔導與推動的重點產業,不論是在光顯示、光儲存光通訊、光輸入、光輸出產業等,歷年來都有不錯的成績。其中尤其是光顯示與光儲存更是占整體產業的大宗。歷年來在掃描器、光碟機、光碟片等多項產品,都曾有位居世界霸主的地位。 自從光碟片問世以來,光碟已經扮演現代科技的重要角色,它既方便攜帶還有儲存容量也大,體積、面積也小了許多,非常符合現代要求如此高效率的時代,而光碟的用途也分成很多類,例如儲存影片、音樂、軟體等等用途,由於光碟的問世,也使得早期使用的磁片、錄音帶、錄影帶等等這些東西,都逐漸被光碟給取代。而光碟從只能儲存聲音的功能,發展到可以儲存影片、軟體等。在這其中,台灣廠商以優異的製造能力與快速擴展產能的策略,建立起光碟片製造王國,總產量佔世界第一,前幾大光碟廠皆為台灣廠商。然而,台灣光碟廠商雖然隨著市場需求而持續成長,但卻始終陷在供過於求的產業困境中,價格快速下跌,加上高額權利金負擔,讓台灣光碟廠陷入經營的窘境。本研究主要是針對紀錄型光碟片產業,收集相關產業資訊,並根據文獻探討擬定研究架構作為產業分析之基本架構;探討過去產業快速成功但卻又深陷供過於求的泥淖的原因,在競爭優勢分析上運用波特競爭理論、五力分析與鑽石理論,並以個案公司為例,瞭解台灣光碟片產業之競爭優勢情形,對產業未來發展提出策略建議。 / Optoelectronics industry has been the focus and promoted by the government. The optical display, optical storage, optical communication, optical input, and optical output industries, have gained good performance in the past years. Especially the scanners, optical disc drives and optical disc media had been the dominant roles in the world。 Since the introduction of the optical disc, it has played an important role in modern high technology. It is convenient to carry over, its large capacity, and the compact size, all meet the requirements of high efficiency. The disc can be used for various purposes of video, music, and data storage and it quickly replaced the floppy discs, audio/video tapes. Taiwan's manufacturers used the strategy to build up the huge capacity rapidly with excellent production capability. The total output has been world number one. However, the market demand continues to grow, but it has been always stuck in oversupply. The rapid declining product prices and the high loyalty burden make the manufacturers in awkward situations. The purpose of this thesis is to focus on analyzing why it succeeded before and why it became oversupply by collecting industry information, literatures, and documents. Based on Porter’s competition theory, theory of five forces analysis and diamond model, and we use A Company as an example to figure out the possible strategies of this industry.
206

Quantum dots : an investigation into how differing surface characteristics affect their interaction with macrophages in vitro

Clift, Martin James David January 2009 (has links)
Quantum dots (QDs) are potentially advantageous tools for both diagnostics and therapeutics due to their light emitting characteristics. The impact of QDs on biological systems however, is not fully understood. The aim of this project therefore, was to investigate the interaction of a series of different surface modifies QDs with macrophages and their subsequent toxicity. CdTe/CdSe (core), ZnS (shell) QDs with either an organic, COOH or NH2 polyethylene glycol (PEG) surface coatings were used. Fluorescent COOH polystyrene beads (PBs) at (Ø) 20nm and 200nm were also studied. J774.A1 murine ‘macrophage-like' cells were treated for two hours with QDs (40nM) of PBs ($50μg.ml^{-1}$) in the presence of 10% FCS prior to assessment of cellular uptake via confocal microscopy and flow cytometry. COOH and $NH_{2}$ (PEG) QDs, as well as 20nm and 200nm PBs entered macrophages within 30 minutes, and were found to locate within endosomes, lysosomes and the mitochondria. T.E.M. also illustrated particles, including organic QDs, to be present inside J774.A1 cells within membrane- bound vesicles at two hours. Organic QDs were unable to be visualised via fixed cell confocal microscopy. Live cell confocal microscopy (without 10% FCS) did suggest however, that organic QDs entered cells in low quantities up to 30 minutes, after which fluorescence declined. Particle toxicity was determined over 48 hours via the MTT, LDH and GSH assays, as well as via assessment of their potential to produce the pro-inflammatory cytokine (TNF-α) and effect cytosolic $Ca^{2+}$ signalling in the J774.A1 cells. Organic QDs were found to be highly toxic at all time points and concentrations used. Both COOH and $NH_{2 }$ (PEG) QDs induced significant (p<0.0001) cytotoxicity (MTT and LDH assays) at 80nM after 48 hours, as well as significant (p<0.01) GSH depletion over 24 hours at all doses, as well as increasing the level of cytosolic $Ca^{2+}$ at 40nM when assessed over 30 minutes. Organic and NH2 (PEG) QDs were found to significantly increase TNF-α production after 24 hours at 80nM. The findings of this study demonstrate that QDs differ in their uptake by macrophages according to their surface coating, with the organic surface coated QDs being the most toxic. At sub-lethal concentrations, in the presence of 10% FCS, the COOH and $NH_{2}$ (PEG) QDs are taken up resulting in GSH depletion and modulated $Ca^{2+}$ signalling, with $NH_{2}$ (PEG) QDs and organic QDs only eliciting limited TNF-α production. Interestingly however, despite these observations, QD surface coating does not affect the intracellular fate of these NPs, with all of the different surface coated QDs observed to be present in endosomes, lysosomes and the mitochondria within J774.A1 macrophage cells. Therefore, in conclusion, the surface coating of QDs plays a significant role in their interaction with macrophages, their uptake and their subsequent toxicity.
207

Uma proposta de modelo para avaliação de websites de comércio eletrônico: aplicação ao varejo de CD'S

Oliveira, Luiz Claudio Barbosa de January 2003 (has links)
Made available in DSpace on 2009-11-18T19:00:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2003 / The aim of this dissertation is to investigate the relationship between the design of website for CD e-commerce and the virtual consumer behavior based on its purchase's attitude and intention. The main goal is to measure the virtual store design effect working as sales agent on Internet. The analysis of the virtual CD retailer was chosen, since the CD is one of the most popular products sold on this channel. This study is based on theoretical framework which describe the following main characteristics: i) Internet play the role as sales channel, ii) the CD retail market and iii) the consumer behavior and its decision processo Further on theoretical reference framework, it is showed the existing different models for website assessment: mo deI based on marketing, theory of two factors, quality assessment, web assessment mo deI (W AM) and the technology acceptance model (T AM). The analysis of its power and weakness will be base to development of the model proposed by this research. The concepts and the methods described were employed to ensure the consistency of its model. The final issue is the research design itself, applying a survey via web. The data collection was used for statistical validation of the relationship on proposed model. The structural equation model (SEM) was the statistical tool for quantitative analysis and to investigate all hypotheses generated on proposed model, supported by the theoretical reference framework. / A dissertação tem como objeto a investigação das relações entre a o design de um website de comércio eletrônico de CDs e o comportamento do consumidor virtual, com ênfase a sua atitude e intenção de compra. O objetivo principal é mensurar o efeito do design da loja virtual (website) em seu papel de agente de vendas na Internet. A análise do comércio varejista de CDs foi escolhida, pois este produto é um dos principais artigos de venda neste canal. O estudo é apoiado em um referencial teórico, no qual são analisadas as características dos seguintes pontos: i) a Internet atuando como canal de vendas; ii) o comércio varejista de CD no Brasil e iii) o comportamento do consumidor e o seu processo decisório. Ainda no referencial teórico são apresentados os diversos modelos de avaliação de website existentes: baseado em Marketing, Teoria dos Dois Fatores, avaliação da qualidade, avaliação da web (W AM) e aceitação da Tecnologia na Web (T AM). A análise e comparação destes modelos serviu como base para o desenvolvimento da proposta do modelo de avaliação website. O estudo é complementado pelo desenvolvimento de uma pesquisa, com aplicação de questionário via web (websurvey). A coleta dos dados é utilizada como forma de validação estatística das relações existentes no modelo desenvolvido. Isto é feito por meio do uso da ferramenta de análise de Equações Estruturadas (SEM), suportada pelos conceitos e métodos de abordagem descritos no referencial teórico. A ferramenta permite tanto avaliar um modelo de mensuração e um modelo estrutural simultaneamente.
208

Relação da imunoexpressão de CD10 e NM23 com as características anatomopatológicas e prognósticos do carcinoma colorretal / Relation of imunoexpression of CD10 and NM23 with the anatomopathologics characteristics and prognostic of colorectal carcinoma

Oliveira, Levindo Alves de [UNIFESP] 27 May 2009 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-05-27. Added 1 bitstream(s) on 2015-08-11T03:25:25Z : No. of bitstreams: 1 Publico-00212.pdf: 1245886 bytes, checksum: 4848d0e58992c5a9ff4b387a14c2534a (MD5) / Objetivos: Analisar a expressão das proteínas CD10 e NM23 por estudo imunohistoquímico do tecido do carcinoma colorretal e da mucosa adjacente. Avaliar a relação da expressão dessas proteínas com os aspectos anatomopatológicos da neoplasia, estadiamento clínico, ocorrência de metástases hepáticas e prognóstico dos doentes. Método: Cento e trinta doentes operados por carcinoma colorretal foram analisados. Bloco de tissue microarray foi confeccionado com tecido neoplásico e com a mucosa não neoplásica adjacente. Estudo imuno-histoquímico foi realizado com anticorpos monoclonais NM23 e CD10 no tecido neoplásico e no tecido não neoplásico da mucosa adjacente. A leitura foi realizada por aparelho de escaneamento de lâminas. A imunoexpressão foi avaliada pelo percentual de células coradas e foram obtidos escores de intensidade. Foram considerados como positivos para CD 10 os tumores que expressavam o marcador em mais de 10% das células neoplásicas. Para NM 23 considerou-se dois grupos divididos em fortes expressores (mais de 50%) e expressores fracos (menos de 50%) das células coradas. Os resultados foram relacionados com as características morfológicas e histopatológicas do carcinoma colorretal, estadiamento clínico, presença de metástases hepáticas e com o prognóstico. No estudo estatístico foram utilizados os testes de Mann-Whitney, Kruskal- Wallis e exato de Fisher. A sobrevivência foi avaliada utilizando a curva de Kaplan- Meier, e o desfecho de comparação entre as curvas foi calculado pelo teste de Long rank. Resultados: Ambos os marcadores CD10 e NM23 apresentaram expressão maior no tecido do carcinoma do que na mucosa não neoplásica adjacente (p<0,0001 para ambos). A imunoexpressão tecidual das proteínas NM23 e CD10 não apresentou relação com o grau de diferenciação celular (p=0,57 e p=0,48, respectivamente), invasão vascular (p=0,85 e p=0,67, respectivamente), invasão linfática (p=0,41 e 0,73, respectivamente), infiltração perineural (p=0,46 e p=0,24, respectivamente) e com o estadiamento pela classificação TNM (p=0,19 para ambos). A imunoexpressão de CD10 no tecido do carcinoma colorretal foi maior (p=0,05) nas neoplasias exofíticas do que nos tumores não exofíticos. A expressão das proteínas NM23 e CD10 não apresentou relação com a incidência de metástases linfonodais (p=0,08 e 0,30, respectivamente). A expressão tecidual dos marcadores NM23 e CD10 não se relacionou com a ocorrência de metástases hepáticas (p=0,59 e p=0,31, respectivamente). A sobrevivência livre de doença mostrou relação significante (p=0,01) com a maior intensidade de imunoexpressão da proteína NM23 no tecido do carcinoma colorretal, o mesmo não ocorrendo com a imunoexpressão da proteína CD10 (p=0,18). A sobrevivência global não mostrou relação com as expressões das proteínas NM23 e CD10 (p=0,13 e p=0,24, respectivamente). Conclusões: O tecido neoplásico do carcinoma colorretal expressou mais intensamente as proteínas NM23 e CD10 do que a mucosa não neoplásica adjacente. A imunoexpressão de CD10 no tecido do carcinoma colorretal foi maior (p=0,05) nas neoplasias exofíticas do que nos tumores não exofíticos. A expressão das proteínas NM23 e CD10 não se relacionou com os demais aspectos anatomopatológicos da neoplasia, com a presença de metástase hepática e com o estadiamento do carcinoma colorretal. Os doentes com imunoexpressão aumentada da proteína NM23 apresentaram sobrevivência livre de doença significativamente maior. A intensidade da imunoexpressão tecidual da proteína CD10 não influenciou a sobrevivência livre de doença e a sobrevivência global não se relacionou com a imunoexpressão das proteínas NM23 e CD10. / Aims: To analyze the tissue expression of the proteins CD 10 and NM 23 through the immunohistochemichal study of the colorectal carcinoma and evaluate the expression relation of these proteins with the anatomopathological aspects of the neoplasia, clinical staging, occurrence of hepatic metastasis and patients’ prognostic. Method: One hundred and thirty operated patients of colorectal carcinoma have been analyzed. A block of tissue microarray was produced with the neoplastic mucosa and with the adjacent non-neoplastic mucosa. An immunohistochemichal study was performed with monoclonal antibodies NM23 and CD10 on the neoplastic tissue and non-neoplastic tissue of the adjacent mucosa. The interpretation of the slides was made by a scanner device. The immunoexpression was evaluated by the percentage of colored cells and the obtained intensity scores. The results were related to the morphological and histopathological characteristics of the carcinoma, clinical staging, presence of hepatic metastasis and to the prognostic of the patients. In the statistic study were used the Mann-Whitney test, the Kruskal-Wallis test and Fisher’s exact test. The analysis of survival was conducted with the use of the Kaplan-Meier curve and the comparison conclusion between the curves was calculated through the Longrank test. Results: Both markers CD10 and NM23 presented a higher expression on the carcinoma tissue rather than on the non-neoplastic adjacent mucosa (p<0,0001 for both). The expression of the proteins NM23 and CD10 did not present any relation to the degree of cellular differentiation (p=0,57 and p=0,48, respectively) , vascular invasion (p=0,85 and p=0,67, respectively), lymphatic invasion (p=0,41and 0,73, respectively), perineural infiltration (p=0,46 and p=0,24, respectively) and with the staging by the TNM classification (p=0,19). The immunoexpression of CD10 on the colorectal carcinoma tissue was higher (p=0,15) on the exophytic neoplasias than on the non-exophytic tumors. The expression of the proteins NM23 and CD10 did not present any relation with the incidence of lymphonodal metastasis (p=0,08 and 0,30, respectively). The tissue expression of the markers NM23 and CD10 did not relate to the occurrence of hepatic metastasis (p=0,59 and 0,31 respectively). The disease-free survival disclosed a significant relation (p=0,01) with a higher intensity of immunoexpression of the protein NM23 on the colorectal carcinoma’s tissue. However, the same did not occur with the immunoexpression of the protein CD10 (p=0,18). The global survival did not show any relation with the expression of the proteins NM23 and CD10 (p=0,13 and p=0,24, respectively). Conclusions: The neoplastic tissue of the colorectal carcinoma expresses more intensely the proteins NM23 and CD10 than the adjacent nonneoplastic mucosa. The expression of the proteins NM23 and CD10 does not relate to the presence of lymphonodal metastasis, hepatic metastasis, degree of cellular differentiation, colonic or rectal localization of the neoplasia, presence of vascular and/or lymphatic invasion, presence of neural infiltration and the staging of the colorectal carcinoma. The patients with increased immunoexpression of the protein NM23 presented a disease-free survival significantly higher. The intensity of the tissue immunoexpression of the protein CD10 did not influence the disease-free survival. The global survival does not relate to the immunoexpression of the proteins NM23 and CD10. / TEDE / BV UNIFESP: Teses e dissertações
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Estudo da interação de líquidos iônicos com proteínas modelo / Study on the interaction of ionic liquids with model proteins.

Juliana Raw 25 October 2016 (has links)
Líquidos iônicos (LIs) são sais que se encontram no estado líquido em temperaturas menores que 100ºC e que vêm ganhando protagonismo na área chamada química verde, prometendo: substituir solventes nocivos ao meio ambiente, aprimorar componentes eletrônicos, favorecer biocatálises dentre outros. Sua alta estabilidade e baixa toxicidade são frequentemente afirmadas, porém, devem ainda ser melhor investigadas. Com o objetivo de implementar o entendimento da interação dos líquidos iônicos com sistemas de relevância biológica, realizamos um estudo sistemático acerca da interação de 3 diferentes líquidos iônicos anfifílicos de mesma cabeça polar e diferentes caudas carbônicas ([C10mim][Cl], [C12mim][Cl] e [C14mim][Cl]) com 3 diferentes proteínas modelo, através das técnicas de absorção óptica, fluorescência, dicroísmo circular (CD) e espalhamento de raios-X a baixos ângulos (SAXS). Para Tanto, utilizamos as proteínas BSA e HSA (Albuminas de Soro Bovino e Humano, respectivamente) além da lisozima. Observamos a supressão da fluorescência das proteínas em todos os casos analisados, onde a diminuição da intensidade correspondeu a, para as proteínas BSA, HSA e lisozima, respectivamente, (55±3)%, (16.1±0.8)% e (4.1±0.2)%, em presença de 0.6mM de [C14mim][Cl], (38±2)%, (13.2±0.7)% e (0.6±0.1)% em presença de 0.6mM de [C12mim][Cl] e (11.0±0.5)%, (9.2±0.5)% e (0.0±0.1)% em presença de 0.6mM de [C10mim][Cl]. Os espectros de absorbância e fluorescência de todos os sistemas nos indicam uma interação de contato entre as proteínas e os líquidos iônicos. Constatamos também o deslocamento do pico de fluorescência, das proteínas BSA e HSA, para menores comprimentos de onda (blue-shift), na medida em que a concentração de LI era aumentada. O máximo deslocamento () alcançado correspondeu a (21±1)nm para ambas albuminas, enquanto que a lisozima não apresentou deslocamento significativo. O blue-shift pode ser explicado pela aproximação das cadeias carbônicas e formações de pontes de hidrogênio nas proximidades dos triptofanos. De acordo com a técnica de SAXS, evidenciamos o aumento do raio de giro das proteínas, na medida em que adicionamos LIs. O raio de giro da BSA, da HSA e lisozima em ausência de LI são (29±1)Å, (30±1)Å e (15±1)Å, respectivamente, e passam para (46±1)Å, (44±1)Å e (20±1)Å respectivamente, em presença de 0.6mM de [C14mim][Cl]. As curvas de SAXS também apresentaram o indício da formação de estruturas micelares a partir de uma dada concentração. Além da alteração em sua estrutura terciária, os dados de CD indicam uma leve perda de estrutura secundária de ambas as albuminas (BSA e HSA), passando de 80 para 65% de -hélice em ausência e presença de 0.6mM de [C14mim][Cl], respectivamente. Sugerimos que as interações das proteínas com os líquidos iônicos, embora inicialmente movidas por forças eletroestática, possuem como principal fator o efeito hidrofóbico, portanto quanto maior a cadeia carbônica do LI maior é sua interação com a proteína. Tal interação causa o desenovelamento das proteínas e formação de um complexo e estruturas micelares a altas concentrações de LI. Acreditamos que este trabalho traz novas informações acerca da interação dos LIs com proteínas modelo, indicando sua capacidade de alterar a conformação das mesmas. / Ionic liquids (ILs) are salts that are liquid at temperatures smaller than 100 ° C and are gaining prominence in the so-called green chemistry, promising: replace harmful solvents to the environment, improve electronic components, and favor biocatalysis, among others. Its high stability and low toxicity are often asserted; nevertheless, they are ascribed to ILs due to its small volatility. With the aim of improving the understanding of the interaction of ILs with biological relevant systems, we conducted a systematic study of the interaction of three different ionic liquids of the same polar head and different paraffinic tails ([C10mim][Cl], [C12mim][Cl] and [C14mim][Cl]) with three different model proteins, through the techniques of optical absorption, fluorescence, circular dicrhoism (CD) and small angle X-ray scattering (SAXS). To do so, we use BSA and HSA proteins (Bovine Serum Albumin and the Human Serum Albumin, respectively) and lysozyme. We observed fluorescence quenching, of all studied proteins, where the decrease in the fluorescence was (for BSA, HAS and lysozyme, respectively): (55 ± 3)%, (16.1 ± 0.8)% to (4.1 ± 0.2 )% in the presence of 0.6mm [C14mim][Cl], (38 ± 2)%, (13.2 ± 0.7)% to (0.6 ± 0.1)% in the presence of 0.6mm [C12mim][Cl] and ( 11.0 ± 0.5)% (9.2 ± 0.5)% and (0.0 ± 0.1)% in the presence of 0.6mm [C10mim][Cl]. UV-vis absorbance spectra and fluorescence indicate all systems in a contact interaction between proteins and ionic liquids. We also note the shift of the fluorescent peak of BSA and HSA proteins for shorter wavelengths (blue-shift), as the IL content was increased. The maximum shift () achieved corresponded to (21 ± 1) nm for both albumins, whereas no significant displacement was observed for lysozyme. The blue-shift can be explained by the approach of carbon chains and formation of hydrogen bonds in the vicinity of tryptophan. SAXS data indicate an increasing in the proteins radius of gyration value as ILs was added in the solution. The turning radius of BSA, HSA and lysozyme in the absence of IL are (29 ± 1) Å, (30 ± 1) Å and (15 ± 1) Å, respectively, and go to (46 ± 1) Å, ( 44 ± 1) Å and (20 ± 1) Å, respectively, in the presence of 0.6mm [C14mim][Cl]. The SAXS curves also show evidence of the formation of micellar structures from a given concentration. Besides the change in its tertiary structure, the CD data indicates a slight loss of secondary structure of both albumins (BSA and HSA), from 80 to 65% of -helix in the absence and presence of 0.6mm [C14mim][Cl], respectively. We suggest that the interactions of the protein with the ionic liquid, although initially driven by electrostatic forces, have a major factor hydrophobic effect and thus the higher the carbon chain of greater IL is its interaction with the protein. This interaction causes unfolding of the protein and formation of a micellar structures at high concentrations of IL. We believe this work provides new information about the interaction of ILs with model proteins, indicating its ability to alter the conformation of the same.
210

Développement du système mixte hydroxypropyl-betacyclodextrine/ liposome en vue de l’encapsulation des constituants des huiles essentielles / Development of drug-in-cyclodextrin-in-liposomes as carrier system for encapsulation of monoterpenes essential oils

Gharib, Riham 13 December 2016 (has links)
L'objectif principal de notre étude a été la mise au point des formulations liposomiales encapsulant des monoterpènes (MT) et phénylpropènes (PP). Le manuscrit contient deux axes principaux. Le premier a porté sur l'interaction de l'HP-ß-CD, de MT et PP avec des membranes lipidiques. L'HP-ß-CD interagit avec les têtes polaires et les chaînes acyles des phospholipides et montre un effet fluidifiant sur les liposomes formés de DPPC et de Lipoid S100. De plus, l'HP-ß-CD présent dans le compartiment aqueux des liposomes les protège durant la lyophilisation. Les MT et PP interagissent avec la tête et les chaînes alkyles de DPPC entrainant sa fluidification. D'autre part, les composés les plus hydrophobes de la série, ont été plus actifs contre E. coli. Le deuxième axe a été orienté vers la préparation des liposomes conventionnels et du système mixte CD/liposome (ACL). La technique de double encapsulation (ACL2) a été appliquée. Les préparations sont faites à partir de Phospholipon 90H ou Lipoid S100 par la méthode d'injection éthanolique. Les vésicules ont été caractérisées pour la taille, pdI, le potentiel zêta, la morphologie, le rendement et la cinétique de libération de la molécule. L'anéthol (Ane) est utilisé comme un système modèle. ACL et ACL2 ont permis d'améliorer le rendement d'encapsulation de l'Ane et de ralentir sa libération. Les liposomes composés de Lipoid S100 ont montré une meilleure photostabilité et rendement d'encapsulation. Le Lipoid S100 a été ainsi utilisé pour la préparation à grande échelle. Les vésicules obtenues à petite et grande échelle, ont présenté les caractéristiques proches ce qui témoigne d'une bonne reproductibilité de ces procédés / The main objective of this work was the development of liposomal formulations encapsulating monoterpenes (MT) and phenylpropene (PP). The manuscript contains two main axes: the first axis was oriented to the interaction of HP-ß-CD, MTs and PPs with lipid membranes. The HP-ß-CD interacts with the polar heads and acyl chains of phospholipids and showed a fluidizing effect on liposomes formed with DPPC or Lipoid S100. In addition, the incorporation of HP-ß-CD in the internal aqueous compartment of the liposomes protected them during lyophilization. The studied monoterpenes interact with the choline head group and the alkyl chains of DPPC membrane raising the bilayer’s fluidity. In addition, the most hydrophobic compounds of the series, were more active against E. coli. The second axis was oriented towards the preparation of conventional liposomes and drug-in-cyclodextrin-in-liposomes (ACL). The double loaded technique (double loaded liposomes, ACL2) was applied. Phospholipon 90H or Lipoid S100 were used to prepare liposomes by the ethanol injection method. Vesicles were characterized in terms of size, pdI, zeta potential, morphology, loading rate and drug release kinetics. Anethole (Ane) is used as a model system. Compared to conventional liposomes, ACL and ACL2 improve the loading rate of Ane and reduce Ane release. Liposomes prepared with Lipoid S100 showed the best photostability and loading rate. Lipoid S100 is used to prepare liposomes at large scale by membrane contactor and by pilot scale. The characteristics of the vesicles obtained at laboratory and large scale confirmed the reproducibility of the two methods of preparation

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