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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.
171

Estudo da monitorização contínua de glicose e das respostas de pressão arterial, frequência cardíaca e de outros parâmetros fisiológicos antes e após treinamento físico em diabéticos tipo II / Study of continuos glucose monitoring and responses in blood pressure, heart rate and others physiological parameters before and after physical training in type II diabetics

Daniele Albano Pinheiro 19 March 2014 (has links)
Há muitas alterações nos sistemas fisiológicos de indivíduos com diabetes melittus em função dos constantes momentos de hiperglicemia, principalmente alterações relacionadas ao aumento dos riscos cardiovasculares. O objetivo desse estudo foi avaliar as respostas do controle glicêmico pelo monitor contínuo de glicose e da pressão arterial (PA), frequência cardíaca (FC) e sua variabilidade expressa pelos valores de RMSSD em diabéticos tipo II submetidos a testes de avaliação antes e após a realização de treinamento aeróbio e resistido. Participaram desse estudo 9 voluntários diabéticos tipo II do sexo masculino (45 a 65 anos) divididos em 3 grupos: DTA (n=7), diabéticos submetidos a seis semanas de treinamento aeróbio; DTR (n=5), diabéticos submetidos a treinamento resistido e GDC (n=5), diabéticos sem qualquer treinamento regular. Os voluntários realizaram testes laboratoriais, ergoespirometria e teste de fadiga em leg press antes e após o treinamento físico. Os resultados foram analisados estatisticamente pelo teste t de Student e pelo teste de Kruskal Wallis. Os voluntários tiveram a cinética da concentração de glicose mensurada pelo monitor contínuo e analisada qualitativamente antes, durante e após a realização da ergoespirometria e do teste de fadiga por 60 minutos. Como resultados o grupo DTA apresentou menores valores de concentração de glicose pela monitorização contínua e o grupo DTR a melhor resposta na cinética dessa curva, apresentando expressivo decaimento na mesma. Em relação à resposta pressórica, somente a PA diastólica (PAD) foi menor estatisticamente para o grupo DTA pós treinamento aeróbio no repouso. Não houve diferenças entre os valores pré e pós treinamentos em relação à FC e os voluntários do grupo DTA apresentaram maiores valores de RMSSD em repouso e o do grupo DTR incrementos desses valores na recuperação dos testes, mostrando maior ação parassimpática no controle autonômico cardíaco dos diabéticos submetidos a treinamentos. Os indivíduos do grupo GDC apresentaram decremento nesse valor, sugerindo piora no controle autonômico cardíaco. Como conclusão geral, este estudo sugere que indivíduos diabéticos tipo II que realizaram treinamento aeróbio e resistido apresentaram benefícios complementares no controle glicêmico registrado pelo monitor contínuo em repouso e no período de recuperação de exercício, respectivamente, adaptações que parecem estar associadas à melhora da ação parassimpática/vagal no controle autonômico cardíaco e, sugere, também, ser o treinamento físico aeróbio o que permite melhor organização hemodinâmica nas respostas de PAD. / There are many changes in physiological systems of people with diabetes melittus due to the constant moments of hyperglycemia, mainly related to increasing of cardiovascular risk. The aim of this study was evaluate the responses of glycemic control by continuos glucose monitoring and blood pressure (BP), heart rate (HR) and its variability expressed by the values of RMSSD in type II diabetics undergoing evaluation tests before and after performing aerobic and resistance training. Participants were 9 volunteers type II diabetic male (45-64 years) divided in 3 groups: DTA (n=7), diabetics undergoing six weeks of aerobic training; DTR (n=5), diabetics undergoing resistance training and GDC (n=5), diabetics without any regular training. The volunteers underwent laboratory tests, spirometry and fatigue tests on leg press before and after physical training. The results were statistically analyzed by Students t and Kruskal Wallis tests. The volunteers had the kinetics of glucose concentration measured by the continuos monitor and qualitatively analyzed before, during and after the spirometry and the fatigue tests for 60 minutes. As a result the DTA group had lower glucose concentration by continuos monitoring and DTR the best response in the kinetic curve, showing important decrease in it. In relation to the BP response, only diastolic BP (DBP) was statistically lower for the DTA group after aerobic training. There were no differences between pre and post training in HR and the DTA group showed higher RMSSD at rest and the DTR group showed increments of these values in the tests recovery showing higher parasympathetic action on cardiac autonomic control in diabetics patients with training. Individuals in the GDC group showed decrement this value, suggesting deterioration in cardiac autonomic control. As a general conclusion, this study suggests that type II diabetic individuals who performed aerobic and resistance training showed additional benefits in glycemic control by continuos monitor recorded at rest and during exercise recovery, respectively, adaptations that seem to be associated with improvement in parasympathetic action in cardiac autonomic control, and also suggests that aerobic exercise training has better organization hemodynamic in responses of DBP.
172

Role of antibodies in autoimmunity of the central nervous system

Cordero Gómez, César 29 October 2019 (has links)
No description available.
173

SOSLite: Soporte para Sistemas Ciber-Físicos y Computación en la Nube

Pradilla Ceron, Juan Vicente 16 January 2017 (has links)
Cyber-Physical Systems (CPS) have become one of the greatest research topics today; because they pose a new complex discipline, which addresses big existing and future systems as the Internet, the Internet of Things, sensors networks and smart grids. As a recent discipline, there are many possibilities to improve the state of the art, interoperability being one of the most relevant. Thus, this thesis has been created within the framework of interoperability for CPS, by using the SOS (Sensor Observation Service) standard, which belongs to the SWE (Sensor Web Enablement) framework of the OGC (Open Geospatial Consortium). It has been developed to give rise to a new line of research within the Distributed Real-Time Systems and Applications group (SATRD for its acronym in Spanish) from the Communications Department of the Polytechnic University of Valencia (UPV for its acronym in Valencian). The approach, with which the interoperability in the CPS has been addressed, is of synthetic type (from parts to whole), starting from a verifiable and workable solution for interoperability in sensor networks, one of the most significant CPSs because it is integrated in many other CPSs, next adapting and testing the solution in more complex CPS, such as the Internet of Things. In this way, an interoperability solution in sensor networks is proposed based on the SOS, but adapted to some requirements that makes of this mechanism a lighter version of the standard, which facilitates the deployment of future implementations due to the possibility of using limited devices for this purpose. This theoretical solution is brought to a first implementation, called SOSLite, which is tested to determine its characteristic behavior and to verify the fulfillment of its purpose. Analogously, and starting from the same theoretical solution, a second implementation is projected called SOSFul, which proposes an update to the SOS standard so that it is lighter, more efficient and easier to use. The SOSFul, has a more ambitious projection by addressing the Internet of Things, a more complex CPS than sensors networks. As in the case of the SOSLite, tests are performed and validation is made through a use case. So, both the SOSLite and the SOSFul are projected as interoperability solutions in the CPS. Both implementations are based on the theoretical proposal of a light SOS and are available for free and under open source licensing so that it can be used by the research community to continue its development and increase its use. / Los Sistemas Ciber-Físicos (CPS) se han convertido en uno de los temas de investigación con mayor proyección en la actualidad; debido a que plantean una nueva disciplina compleja, que aborda sistemas existentes y futuros de gran auge como: la Internet, la Internet de las Cosas, las redes de sensores y las redes eléctricas inteligentes. Como disciplina en gestación, existen muchas posibilidades para aportar al estado del arte, siendo la interoperabilidad uno de los más relevantes. Así, esta tesis se ha creado en el marco de la interoperabilidad para los CPS, mediante la utilización del estándar SOS (Sensor Observation Service) perteneciente al marco de trabajo SWE (Sensor Web Enablement) del OGC (Open Geospatial Consortium). Se ha desarrollado para dar surgimiento a una nueva línea de investigación dentro del grupo SATRD (Sistemas y Aplicaciones de Tiempo Real Distribuidos) del Departamento de Comunicaciones de la UPV (Universitat Politècnica de València). La aproximación con la cual se ha abordado la interoperabilidad en los CPS es de tipo sintética (pasar de las partes al todo), iniciando desde una solución, verificable y realizable, para la interoperabilidad en las redes de sensores, uno de los CPS más significativos debido a que se integra en muchos otros CPS, y pasando a adaptar y comprobar dicha solución en CPS de mayor complejidad, como la Internet de las Cosas. De esta forma, se propone una solución de interoperabilidad en las redes de sensores fundamentada en el SOS, pero adaptada a unos requerimientos que hacen de este mecanismo una versión más ligera del estándar, con lo que se facilita el despliegue de futuras implementaciones debido a la posibilidad de emplear dispositivos limitados para tal fin. Dicha solución teórica, se lleva a una primera implementación, denominada SOSLite, la cual se prueba para determinar su comportamiento característico y verificar el cumplimiento de su propósito. De forma análoga y partiendo de la misma solución teórica, se proyecta una segunda implementación, llamada SOSFul, la cual propone una actualización del estándar SOS de forma que sea más ligero, eficiente y fácil de emplear. El SOSFul, tiene una proyección más ambiciosa al abordar la Internet de las Cosas, un CPS más complejo que las redes de sensores. Como en el caso del SOSLite, se realizan pruebas y se valida mediante un caso de uso. Así, tanto el SOSLite como el SOSFul se proyectan como soluciones de interoperabilidad en los CPS. Ambas implementaciones parten de la propuesta teórica de SOS ligero y se encuentran disponibles de forma gratuita y bajo código libre, para ser empleados por la comunidad investigativa para continuar su desarrollo y aumentar su uso. / Els sistemes ciberfísics (CPS, Cyber-Physical Systems) s'han convertit en un dels temes de recerca amb major projecció en l'actualitat, a causa del fet que plantegen una nova disciplina complexa que aborda sistemes existents i futurs de gran auge, com ara: la Internet, la Internet de les Coses, les xarxes de sensors i les xarxes elèctriques intel·ligents. Com a disciplina en gestació, hi ha moltes possibilitats per a aportar a l'estat de la qüestió, sent la interoperabilitat una de les més rellevants. Així, aquesta tesi s'ha creat en el marc de la interoperabilitat per als CPS, mitjançant la utilització de l'estàndard SOS (Sensor Observation Service) pertanyent al marc de treball SWE (Sensor Web Enablement) de l'OGC (Open Geospatial Consortium). S'ha desenvolupat per a iniciar una nova línia de recerca dins del Grup de SATRD (Sistemes i Aplicacions de Temps Real Distribuïts) del Departament de Comunicacions de la UPV (Universitat Politècnica de València). L'aproximació amb la qual s'ha abordat la interoperabilitat en els CPS és de tipus sintètic (passar de les parts al tot), iniciant des d'una solució, verificable i realitzable, per a la interoperabilitat en les xarxes de sensors, un dels CPS més significatius pel fet que s'integra en molts altres CPS, i passant a adaptar i comprovar aquesta solució en CPS de major complexitat, com la Internet de les Coses. D'aquesta forma, es proposa una solució d'interoperabilitat en les xarxes de sensors fonamentada en el SOS, però adaptada a uns requeriments que fan d'aquest mecanisme una versió més lleugera de l'estàndard, amb la qual cosa es facilita el desplegament de futures implementacions per la possibilitat d'emprar dispositius limitats a aquest fi. Aquesta solució teòrica es porta a una primera implementació, denominada SOSLite, que es prova per a determinar el seu comportament característic i verificar el compliment del seu propòsit. De forma anàloga i partint de la mateixa solució teòrica, es projecta una segona implementació, anomenada SOSFul, que proposa una actualització de l'estàndard SOS de manera que siga més lleuger, eficient i fàcil d'emprar. El SOSFul té una projecció més ambiciosa quan aborda la Internet de les Coses, un CPS més complex que les xarxes de sensors. Com en el cas del SOSLite, es realitzen proves i es valida mitjançant un cas d'ús. Així, tant el SOSLite com el SOSFul, es projecten com a solucions d'interoperabilitat en els CPS. Ambdues implementacions parteixen de la proposta teòrica de SOS lleuger, i es troben disponibles de forma gratuïta i en codi lliure per a ser emprades per la comunitat investigadora a fi de continuar el seu desenvolupament i augmentar-ne l'ús. / Pradilla Ceron, JV. (2016). SOSLite: Soporte para Sistemas Ciber-Físicos y Computación en la Nube [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/76808 / TESIS
174

Analýza akustických a vibračních parametrů od železniční dopravy / Analysis of acoustic and vibration parameters from rail transport

Turčíková, Hana January 2014 (has links)
This diploma thesis is focused on operational testing of selected railway lines with different structures of superstructure. For the measurement purposes suitable measuring sections in directional curves on the rail corridors were chosen and suitable measuring methodology was designed. Based on all the tests the dynamic and acoustic parameters of tested structures were determined. For the test evaluations suitable mathematic methods in both time and frequency zone was chosen. Part of my work is also to compare the parameters of the tested structures and to make recommendations for practise.
175

Vliv rozptýlené výztuže na fyzikálně-mechanické parametry výsledného kompozitu / Influence of dispersed reinforcement on the physico-mechanical properties of the resulting composite

Láník, Jaromír Unknown Date (has links)
The dissertation is focused on the issue of implementation and evaluation of the laboratory tests fiber reinforced concrete. The issue of steel fiber is solved in terms of their physico-mechanical parameters, which are an important part of their design and reliable operation in the product design. The experimental part of the thesis is focused on laboratory tests of steel fiber of different strength classes and different weight benefits of steel fibers, the default reference mixture of plain concrete are certified mixtures commonly used as structural concrete in construction. The evaluation of the testing of samples produced steel fiber is made by three selected recommending regulations for the design and testing of structural steel fiber. In conclusion, the individual obtained experimental results are compared.
176

Especificación y desarrollo de una pasarela física y virtual para interoperabilidad de dispositivos heterogéneos en el ámbito de Internet de las Cosas

Olivares Gorriti, Eneko 21 March 2022 (has links)
[ES] En los últimos años, Internet de las cosas (``Internet of Things'' o ``IoT'') ha evolucionado de ser simplemente un concepto académico, construido alrededor de protocolos de comunicación y dispositivos, a ser un ecosistema con aplicaciones industriales y de negocio con implicaciones tecnológicas y sociales sin precedentes. Gracias a las nuevas redes de acceso inalámbricas emergentes, sensores mejorados y sistemas embebidos con procesadores cada vez más eficientes y baratos, una gran cantidad de objetos (tanto de nuestra vida cotidiana como de sistemas y procesos industriales) están interconectados entre sí, trasladando la información del mundo físico a las aplicaciones y servicios de Internet. A través de las pasarelas IoT los dispositivos que interactúan con el mundo físico son capaces de conectarse a las redes de comunicación e intercambiar información. Son varios los retos que deben afrontar las pasarelas en su papel dentro del Internet de las Cosas, entre ellas, la escalabilidad, seguridad, la gestión de dispositivos y, recientemente, la interoperabilidad. La falta de interoperabilidad entre los dispositivos provoca importantes problemas tecnológicos y empresariales, tales como la imposibilidad de conectar dispositivos IoT no interoperables a plataformas IoT heterogéneas, la imposibilidad de desarrollar aplicaciones IoT que exploten múltiples plataformas en dominios homogéneos y/o cruzados, la lentitud en la introducción de la tecnología IoT a gran escala, el desánimo en la adopción de la tecnología IoT, el aumento de los costes, la escasa reutilización de las soluciones técnicas y la insatisfacción de los usuarios. El propósito de esta tesis doctoral es la búsqueda de una solución óptima para la interoperabilidad entre dispositivos de Internet de las Cosas mediante la definición de una pasarela IoT genérica, modular y extensible; sin dejar de lado aspectos esenciales como la seguridad, escalabilidad y la calidad de servicio. Se completa esta tesis doctoral con una implementación software de la pasarela IoT siguiendo la definición propuesta, así como el despliegue y la evaluación de los resultados obtenidos en numerosos casos de uso pertenecientes a pilotos del proyecto de investigación Europeo ``INTER-IoT'' financiado a través del programa marco Horizonte 2020. / [CA] En els últims anys, Internet de les coses (``Internet of Things'' o ``IoT'') ha evolucionat de ser simplement un concepte acadèmic, construït al voltant de protocols de comunicació i dispositius, a ser un ecosistema amb aplicacions industrials i de negoci amb implicacions tecnològiques i socials sense precedents. Gràcies a les noves xarxes d'accés ``wireless'' emergents, sensors millorats i sistemes embeguts amb processadors cada vegada més eficients i barats, una gran quantitat d'objectes (tant de la nostra vida quotidiana com de sistemes i processos industrials) estan interconnectats entre si, traslladant la informació del món físic a les aplicacions i serveis d'Internet. A través de les passarel·les IoT els dispositius que interactuen amb el món físic són capaços de connectar-se a les xarxes de comunicació i intercanviar informació. Són diversos els reptes que han d'afrontar les passarel·les en el seu paper dins de la Internet de les Coses, entre elles, l'escalabilitat, seguretat, la gestió de dispositius i, recentment, la interoperabilitat. La falta d'interoperabilitat entre els dispositius provoca importants problemes tecnològics i empresarials, com ara la impossibilitat de connectar dispositius IoT no interoperables a plataformes IoT heterogènies, la impossibilitat de desenvolupar aplicacions IoT que exploten múltiples plataformes en dominis homogenis i/o croats, la lentitud en la introducció de la tecnologia IoT a gran escala, el descoratjament en l'adopció de la tecnologia IoT, l'augment dels costos, l'escassa reutilització de les solucions tècniques i la insatisfacció dels usuaris. El propòsit d'aquesta tesi doctoral és la cerca d'una solució òptima per a la interoperabilitat entre dispositius d'Internet de les Coses mitjançant la definició d'una passarel·la IoT genèrica, modular i extensible; sense deixar de costat aspectes essencials com la seguretat, escalabilitat i la qualitat de servei. Es completa aquesta tesi doctoral amb una implementació programari de la passarel·la IoT seguint la definició proposada, així com el desplegament i l'avaluació dels resultats obtinguts en nombrosos casos d'ús pertanyents a pilots del projecte d'investigació Europeu ``INTER-IoT'' finançat a través del programa marc Horitzó 2020. / [EN] In recent years, the Internet of Things (``IoT") has evolved from being simply an academic concept, built around communication protocols and devices, to an ecosystem with industrial and business applications with unprecedented technological and social implications. Thanks to new emerging wireless access networks, improved sensors and embedded systems with increasingly efficient and inexpensive processors, a large number of objects (both in our daily lives and in industrial systems and processes) are interconnected with each other, moving information from the physical world to Internet applications and services. Through IoT gateways, devices that interact with the physical world are able to connect to communication networks and exchange information. There are several challenges that gateways must face in their role within the Internet of Things, including scalability, security, device management and, recently, interoperability. The lack of interoperability between devices causes major technological and business problems, such as the impossibility of connecting non-interoperable IoT devices to heterogeneous IoT platforms, the impossibility of developing IoT applications that exploit multiple platforms in homogeneous and/or cross-domains, the slow introduction of IoT technology on a large scale, discouragement in the adoption of IoT technology, increased costs, low utilization of technical solutions and user dissatisfaction. The purpose of this doctoral thesis is the search for an optimal solution for interoperability between Internet of Things devices by defining a generic, modular and extensible IoT gateway; without neglecting essential aspects such as security, scalability and quality of service. This doctoral Thesis is completed with a software implementation of the IoT gateway following the proposed definition, as well as the deployment and evaluation of the results obtained in numerous use cases belonging to the pilots of the European research project ``INTER-IoT'' funded through the Horizon 2020 framework program. / Esta tesis doctoral se completa con una implementación software de la pasarela IoT siguiendo la definición propuesta, así como el despliegue y la evaluación de los resultados obtenidos en numerosos casos de uso pertenecientes a pilotos del proyecto de investigación Europeo “INTER-IoT” financiado a través del programa marco Horizonte 2020. / Olivares Gorriti, E. (2022). Especificación y desarrollo de una pasarela física y virtual para interoperabilidad de dispositivos heterogéneos en el ámbito de Internet de las Cosas [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/181492 / TESIS
177

ODMR-Untersuchungen an Terbium-Gallium-Granat und Kaliumtantalat

Faust, Bernd 08 September 2000 (has links)
An zwei verschiedenen Kristall-Typen, an Tb3Ga3O12 (TGG) und an KTaO3, konnten die prinzipiellen Vorteile der ODMR-Technik (optisch detektierte magnetische Resonanz) gegenüber der konventionellen ESR (Elektronenspinresonanz) durch die erzielten interessanten Untersuchungsergebnisse belegt werden. Die ODMR-Technik ermöglichte Spinresonanz-Untersuchungen an TGG. Dieses Material ist durch sein paramagnetisches Grundgitter für konventionelle ESR nicht zugänglich. Das für den "bulk"-Paramagnetismus verantwortliche Tb3+ konnte in allen Kristallen nachgewiesen werden. Die Identifizierung erfolgte durch Untersuchungen der Proben über MCD (magnetic circular dichroism), ODMR via MCD, ODMR via den Faraday-Effekt und zusätzlichen theoretischen Betrachtungen mit Hilfe von Kristallfeld-Rechnungen. Bei dem zweiten in TGG identifizierten Zentrum handelt es sich um Ce3+, dessen ODMR interessanterweise vor dem starken paramagnetischen Hintergrund durch das Tb-Untergitter beobachtbar ist. Dieser Defekt ist nur in den Ca/Ce-dotierten Proben mit Ce-Überschuß nachweisbar - was vermuten läßt, daß Ce zur Ladungskompensation der Ca2+-Defekte auf Tb3+- und Ga3+-Plätzen nur vierwertig eingebaut wird. Ist die Ce-Dotierung dagegen höher als zur Ladungskompensation nötig, so wird es vorwiegend dreiwertig eingebaut. Es wurde durch Vergleich von MCD-, LD- und Spektren der optischen Absorption gezeigt, daß Ce3+ das photochrome Zentrum ist, welches für einen speziellen photorefraktiven Effekt in TGG verantwortlich ist. Der zweite Teil dieser Arbeit gilt der Untersuchung von Fe-dotiertem KTaO3 mit den Methoden der ODMR. Im Vergleich zum TGG konnte hier eine überraschend große Anzahl verschiedener Zentren identifiziert und über deren Spinresonanz und optische Eigenschaften charakterisiert werden. Für das aus ESR-Untersuchungen bereits bekannte axiale Fe3+-Oi -Zentrum wurde anhand dessen tagged MCD-Messungen gezeigt, daß die optischen Übergänge dieses unsere Kristalle dominierenden Defektes erstaunlich weit in den roten Spektralbereich hineinreichen. Der Nachweis der optischen Orientierbarkeit dieses molekülartigen Defekt-Komplexes stellt ein weiteres sehr interessantes Ergebnis dieser Arbeit dar. Das in den "as grown" Kristallen metastabil vorhandene (ebenfalls axiale) Fe4+-Oi konnte zum ersten Mal beobachtet werden. Durch Oxidationsbehandlungen (Absenken des Fermi-Niveaus) der Fe-dotierten KTaO3 -Proben läßt sich erreichen, daß Fe4+-Oi bei tiefen Temperaturen als stabiler Zustand vorhanden ist. In reduzierten Proben konnte ein weiteres in zwei Ladungsstufen auftretendes Zentrenpaar identifiziert werden. Das axiale Fe3+-Vo war durch ESR-Untersuchungen bereits bekannt und ist bei X-Band MW-Frequenzen allein über die ESR vom Fe3+-Oi nicht zu unterscheiden. Der MCD des Fe3+-Vo mit einer Bande bei 370 nm unterscheidet sich jedoch sehr deutlich von den bis ins Rote reichenden MCD-Banden des Fe3+-Oi. Je nach Reduktionsgrad der Probe ist der Defekt in der Ladungsstufe Fe2+-Vo zugleich präsent oder kann durch eine Umladungsbeleuchtung erzeugt werden. Dieses neu entdeckte Zentrum besitzt eine dem Fe4+-Oi ähnliche ODMR-Winkelabhängigkeit. Zusätzlich zu den vielen axialen Fe-Zentren zeigte sich auch ein Fe3+-Zentrum in lokaler rhombischer Symmetrie. Die Betrachtung der für diesen Defekt signifikanten Spin-Hamilton-Parameter von Helium bis Raumtemperatur ermöglichte es, die zwei in der Literatur diskutierten Fe3+rh-Zentren auf ein einziges Zentrum zurückzuführen. Das nur metastabil und mit axialer Symmetrie auftretende O--Zentrum wurde auch in nicht Fe-dotierten KTaO3-Kristallen entdeckt. Neben der Untersuchung der erwähnten Defekte wurde eine erhöhte Aufmerksamkeit den in der Polarisationsspektroskopie (prinzipbedingt) häufig auftretenden Artefakten gewidmet.
178

Follicular Dendritic Cells, Human Immunodeficency Virus Type 1, and Alpha 1 Antitrypsin

Zhou, Xueyuan 08 March 2012 (has links) (PDF)
HIV/AIDS is raging and causing millions of deaths around the world. The major challenge in treating HIV/AIDS is the establishment of HIV reservoirs where the viruse escapes both drug and immune system attempts at eradication. Throughout the course of HIV/AIDS, productive HIV infection occurs primarily in the lymphoid follicles or germinal centers (GC) surrounding follicular dendritic cells (FDC). In the GCs, FDCs trap and maintain infectious HIV for years and provide these infectious viruses to the host cells. FDCs also attract B and T cells into the GCs and increase the ability of CD4+ T cells to be infected. Additionally, FDCs also mediate the increase of HIV replication in HIV-infected CD4+ T cells. Recently, several clinical cases and in vitro studies suggest that alpha-1-antitrypsin (AAT) might inhibit HIV infection and replication. Therefore, I hypothesized that AAT inhibited both the infection and replication of HIV in primary CD4+ T cells. I also postulated that AAT inhibited the FDC-mediated contributions that potentiate HIV infection and replication. To test whether AAT inhibited HIV infection in lymphocytes, CD4+ T cells were pretreated with AAT and then incubated with HIV to detect HIV infection. To exam whether AAT inhibited HIV replication, infected CD4+ T cells were cultured with AAT to detect the replication of HIV. To determine whether AAT blocked the FDC-mediated contributions to HIV pathogenesis, activated or resting FDCs were treated with AAT to detect the trapping and maintenance of HIV. The results suggested that AAT inhibited HIV entry into CD4+ T cells by directly interacting with gp41 and thereby inhibiting the interaction between HIV and CD4+ T cells. AAT also inhibited HIV replication in infected CD4+ T cells. Further study revealed that AAT interacted with low-density lipoprotein-receptor related protein to mediate the internalization of AAT through a clathrin-dependent endocytic process in CD4+ T cells. Subsequently, internalized AAT was transported from the endosome to the lysosome and then released into the cytosol. In the cytosol, AAT directly interacted with IκBα to block its polyubiquitinylation at lysine residue 48, which resulted in the accumulation of phosphorylated/ubiqutinylated IκBα in the cytosol. In turn, the dissociation of IκBα from NF-κB was blocked, which thereby inhibited the nuclear translocation and activation of NF-κB. Additionally, AAT also down-regulated FDC-CD32 and FDC-CD21 expression, which are regulated by NF-kB, thereby inhibiting the trapping and maintenance of HIV on FDCs. Hence, AAT not only suppresses HIV replication, but also blocks HIV replication in CD4+ T cells. Moreover, AAT also inhibits the activation of FDCs thereby affecting the trapping and maintenance of HIV.
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The Role of Membrane Lipid Microdomains (Rafts) in FcγRIIA Effector Functions

Vieth, Joshua A. 24 May 2010 (has links)
No description available.
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Efeito da inflamação no peptídeo natriurético atrial (NT-proBNP) em pacientes com espondilite anquilosante ativa durante terapia anti-TNF / Effect of inflammation on atrial natriuretic peptide (NT-proBNP) levels in active ankylosing spondylitis patients receiving anti-TNF therapy

Moraes, Júlio César Bertacini de 21 October 2013 (has links)
Introdução: O fragmento amino-terminal do pró-peptídeo natriurético do tipo B (NT-proBNP) é um forte marcador de doença cardiovascular com evidências recentes de que a inflamação também pode influenciar seus valores. A diferenciação dessa variável de confusão é de particular interesse nas doenças reumáticas. Objetivos: Avaliar o comportamento dos valores de NT-proBNP em pacientes com espondilite anquilosante (EA) pré e pós uso de bloqueadores de TNF para determinar a possível associação entre os valores de NT-proBNP e os parâmetros inflamatórios. Métodos: Quarenta e cinco pacientes consecutivos com EA sem evidência prévia ou atual de doença cardiovascular ou disfunção miocárdica sistólica e que eram elegíveis para terapia anti-TNF foram incluídos prospectivamente. Todos os pacientes receberam bloqueadores de TNF e foram avaliados para concentrações circulantes de NT-proBNP, parâmetros clínicos e laboratoriais de atividade de doença, fatores de risco cardiovasculares tradicionais e ecodopplercardiografia convencional e tecidual no momento da inclusão e após seis meses de tratamento. Resultados: No momento da inclusão, todos os pacientes tinham EA ativa, os valores de NT-proBNP tinham uma mediana de 36 (20-72) pg/mL e 11% dos valores estavam altos mesmo na ausência de alteração miocárdica sistólica. A análise de regressão linear múltipla revelou que esse peptídeo estava independentemente correlacionado com o VHS (p < 0,001), com a idade dos pacientes (p = 0,01) e com a pressão de pulso (p = 0,01) no momento da inclusão. Após seis meses, todos os parâmetros relacionados a doença de base melhoraram e os valores de NT-proBNP se reduziram significativamente [24 (16-47) pg/mL, p = 0,037] quando comparados com os valores do momento da inclusão. As mudanças nos valores de NT-proBNP correlacionaram-se positivamente com as mudanças nos valores do VHS (r = 0,41, p = 0.006). Os fatores de risco cardiovasculares avaliados permaneceram estáveis durante o seguimento. Conclusão: As elevações nos valores de NT-proBNP devem ser interpretadas com cuidado nos pacientes com EA ativa e sem evidência de doença cardiovascular. A redução no curto prazo dos valores de NT-proBNP nesses pacientes recebendo terapia anti-TNF parece refletir uma melhora do estado inflamatório / Introduction: N-terminal pro-brain natriuretic peptide (NT-proBNP) is a strong marker of cardiovascular disease with recent evidence that inflammation may also influence its levels; discrimination of this confounding variable is of particular interest in rheumatic diseases. Objectives: to evaluate NT-proBNP in ankylosing spondylitis (AS) patients pre- and post-TNF blocker to determine the possible association between NT-proBNP levels and inflammatory parameters. Methods: Forty-five consecutive AS patients without previous/current cardiovascular disease or systolic myocardial dysfunction, who were eligible to anti-TNF therapy, were prospectively enrolled. All patients received TNF blockers and they were evaluated for circulating NT-proBNP levels, clinical and laboratory parameters of disease activity, traditional cardiovascular risk factors, and conventional and tissue Doppler imaging echocardiography at baseline (BL) and six months after (6M) treatment. Results: At BL, all patients had active AS, NT-proBNP levels had a median of 36 (20-72) pg/mL and 11% were high in spite of no systolic alteration. Multiple linear regression analysis revealed that this peptide, at BL, was independently correlated with ESR (p < 0.001), age (p = 0.01) and pulse pressure (p = 0.01). After 6M, all disease parameters improved and NT-proBNP levels were significantly reduced [24 (16-47) pg/mL, p = 0.037] compared to BL. Changes in NT-proBNP were positively correlated with ESR changes (r = 0.41, p = 0.006). Cardiovascular risk factors remained stable during follow-up. Conclusion: our data suggests that elevations of NT-proBNP should be interpreted with caution in active AS patients with no other evidence of cardiovascular disease. The short-term reduction of NT-proBNP levels in these patients receiving anti-TNF therapy appears to reflect an improvement in inflammatory status

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