Ancoragem na movimentação ortodôntica

Uma ancoragem eficiente é um factor de extrema importância em Ortodontia. Perante a relevância deste assunto e sendo ainda um desafio para muitos ortodontistas, este trabalho tem como objetivo realizar uma revisão bibliográfica sobre dispositivos de ancoragem, especificamente mini-implantes e mini-placas, entendendo que os mesmos surgiram como auxiliares importantes no tratamento ortodôntico, com a finalidade de relacionar os tipos, indicações, aplicações clínicas, locais de instalação, vantagens, possíveis complicações na sua utilização e cuidados a serem tomados. Alta versatilidade de aplicação clínica, eliminação de movimentos indesejáveis dos dentes pilares, movimentos precisos, movimentos mais rápidos, redução de custos, processo cirúrgico simples e pouco invasivo, substituição de aparelhos extraorais, tamanho reduzido e capacidade de suportar de imediato forças ortodônticas pesadas, são algumas das vantagens na utilização dos mini-implantes e mini-placas que fazem com que a ancoragem óssea absoluta obtida através do seu uso crie melhores condições na obtenção dos objetivos propostos no tratamento ortodôntico com aparatologia fixa.

Integrin traffic and signalling – from plasma membrane to endosomes

Integrins are the main cell surface receptors by which cells adhere to the surrounding extracellular matrix (ECM). Cells regulate integrin-mediated adhesions by integrin endo/exocytic trafficking or by altering the integrin activation status. Integrin binding to ECM-components induces several intracellular signalling cascades, which regulate almost every aspect of cell behaviour from cell motility to survival, and dysregulation of integrin traffic or signalling is associated with cancer progression. Upon detachment, normal cells undergo a specialised form of programmed cell death namely anoikis and the ECM-integrin -mediated activation of focal adhesion kinase (FAK) signalling at the cell surface has been considered critical for anoikis suppression. Integrins are also constantly endocytosed and recycled back to the plasma membrane, and so far the role of integrin traffic in cancer has been linked to increased adhesion site turnover and cell migration. However, different growth factor receptors are known to signal also from endosomes, but the ability of integrins to signal from endosomes has not been previously studied. In this thesis, I demonstrate for the first time that integrins are signalling also from endosomes. In contrast to previous believes, integrin-induced focal adhesion kinase (FAK) signalling occurs also on endosomes, and the endosomal FAK signalling is critical for anoikis suppression and for cancer related processes such as anchorage-independent growth and metastasis. Moreover, we have set up a new integrin trafficking assay and demonstrate for the first time in a comprehensive manner that active and inactive integrins undergo distinct trafficking routes. Together these results open up new horizons in our understanding of integrins and highlight the fundamental connection between integrin traffic and signalling.

Remoción del barrillo dentario después de la preparación del espacio para el poste: requisito u omisión

El pronóstico a largo plazo de una pieza dental tratada endodónticamente depende de una adecuada rehabilitación definitiva que evitará la recontaminación del sistema del conducto radicular, permitiendo a su vez restituir de forma efectiva su función y estética en boca. La colocación de postes dentro del conducto radicular está indicada cuando el sustrato dental residual es muy limitado, permitiendo al especialista reconstruir la estructura dentaria para que la restauración futura pueda ser retenida. Diversos estudios concluyen que los postes de fibra de vidrio son una de las mejores alternativas para establecer un anclaje seguro entre la pieza dental y la restauración, los cuales son retenidos en el interior del conducto radicular mediante cementos resinosos en combinación con sistemas adhesivos. Este anclaje puede modificarse por diversos factores que pueden ser dependientes del operador como la elección de protocolos químiomecánicos en la terapia endodóntica y al momento de la preparación del espacio para el poste, o independientes del operador, como la anatomía del conducto radicular, formación de la capa barrillo dentinario durante la desobturación, el sustrato de adhesión, mecanismos endógenos y comportamiento de los materiales. Por lo tanto el presente estudio plantea una revisión de las variables a las que se enfrenta el especialista para obtener una adecuada retención del poste al conducto radicular por medio de cementos adhesivos, proponiendo diversos protocolos de irrigación y dispositivos coadyuvantes basados en evidencia científica que ayudaran a neutralizar los efectos adversos que el operador puede controlar.

Use of Fiber Reinforced Polymer Composite Cable for Post-tensioning Application

Corrosion of steel tendons is a major problem for post-tensioned concrete, especially because corrosion of the steel strands is often hard to detect inside grouted ducts. Non-metallic tendons can serve as an alternative material to steel for post-tensioning applications. Carbon fiber reinforced polymer (CFRP), given its higher strength and elastic modulus, as well as excellent durability and fatigue strength, is the most practical option for post-tensioning applications. The primary objective of this research project was to assess the feasibility of the use of innovative carbon fiber reinforced polymer (CFRP) tendons and to develop guidelines for CFRP in post-tensioned bridge applications, including segmental bridges and pier caps. An experimental investigation and a numerical simulation were conducted to compare the performance of a scaled segmental bridge model, post-tensioned with two types of carbon fiber strands and steel strands. The model was tested at different prestress levels and at different loading configurations. While the study confirms feasibility of both types of carbon fiber strands for segmental bridge applications, and their similar serviceability behavior, strands with higher elastic modulus could improve structural performance and minimize displacements beyond service loads. As the second component of the project, a side-by-side comparison of two types of carbon fiber strands against steel strands was conducted in a scaled pier cap model. Two different strand arrangements were used for post-tensioning, with eight and six strands, respectively representing an over-design and a slight under-design relative to the factored demand. The model was tested under service and factored loads. The investigation confirmed the feasibility of using carbon fiber strands in unbonded post-tensioning of pier caps. Considering both serviceability and overload conditions, the general performance of the pier cap model was deemed acceptable using either type of carbon fiber strands and quite comparable to that of steel strands. In another component of this research, creep stress tests were conducted with carbon fiber composite cable (CFCC). The anchorages for all the specimens were prepared using a commercially available expansive grout. Specimens withstood 95% of the guaranteed capacity provided by the manufacturer for a period of five months, without any sign of rupture.

Estudio molecular en dos hermanas afectadas por ictiosis congénita autosómica recesiva : descripción de una nueva mutación causal en TGM1

Se describe la variante homocigota c.320-2A>G de TGM1 en dos hermanas con ictiosis congénita autosómica recesiva. El clonaje de los transcritos generados por esta variante permitió identificar tres mecanismos moleculares de splicing alternativos.

Vihara architecture: defining the existential foothold of VIII century Buddhist monastery "Somapura Mahavihara" of ancien Bengal

Lost in history, the ruin of ‘Somapura Mahavihara’ was not recognized separated from its birthplace, i.e. nature, for more than 700 years. Yet, within its silent presence, the monument dominated the name of the region: ‘Paharpur’ (land of hillock), according to its appearance surrounds by its flat land topo¬graphy. Discovered in 1919, the single largest Buddhist Vihara (monas¬tery) of ancient Bengal came into light, pronouncing the flou¬rishing minute of Buddhist architecture, once dominant religious force of the subcontinent. The earliest historical monumental architecture of greater Asia, had long been deriving itself from the Buddhist monastic architecture as early as VI century BC. In line of history, the discovery of ‘Somapura Mahavihara’ contributed attesting the sensitivities of a highly sophisticated architectonic typology of Vihara Architecture in the land of ancient Bengal. The recovery of ‘Somapura Mahavihara’ was not only from its cradle of nature, but also from its remarkable existence imprinted in the reign of Pala dynasty (750 - 1155 AD) announcing the existential foothold of man in his nature. The existential foothold of ‘Somapura Mahavihara’ comprises the factors, responsible in shaping the anchorage of the mo¬nument since the birth of Vihara architecture, as early as 530 BC. These factors not only denote the building technology in response to its environment but also the amalgamation of be¬lief, upon which the dwellers transformed the site as a place announcing their existence on earth. This research paper aims at exploring the existential foothold of ‘Somapura Mahavihara’, in terms of its territorial, functional, structural, social, cultural, religious sym¬bolic hierarchies of human achievement while clarifying the architectonic typology that shaped ‘Somapura Mahavihara’ through evolution process of ‘Vihara Architecture’. This understanding intends to combine the archaeological knowledge with comparative architectural analysis of contem¬porary Viharas of ancient Bengal, to define the singularity of ‘Somapura Mahavihara’. In consequence, the glorious past of ‘Somapura Mahavihara’ is intended to portray through iden¬tifying the relation of religious and functional rationalism with the connotation of art, architecture and belief moulded within natural forces, as one complete entity; RESUMO: Vihara Arquitetura: Definindo a posição existencial do século VIII Budista mosteiro “Somapura Mahavihara” de Bengala antiga. Perdidas na História, as ruínas de ‘Somapura Mahavihara’ foram confundidas com uma montanha durante mais de setecentos anos. Contudo, no seu silêncio presente, o monumento marcou a toponímia da região; ‘Paharpur’ significa ‘a terra do outeiro’, evidenciando a singularidade deste monumento numa região dominada por uma extensa planície. Em 1919, foi descoberto o maior mosteiro budista da antiga região de Bengal, demonstrando a prosperidade da arquitectura budista. Tem¬poralmente, a descoberta de ‘Somapura Mahavihara’ contribuiu para atestar a evolução e a sofisticação da tipologia arquitectónica denominada ‘Arquitectura Vihara’, existente na antiga região de Bengal. A noção de pegada existencial de ‘Somapura Mahavihara’ compreende os factores responsáveis por moldar a ancoragem do monumento ao lugar em que se insere desde o início da arquitectura Vihara, que remonta a 530 a.C. Estes factores evidenciam a tecnologia construtiva empregue para responder ao ambiente envolvente mas também a evolução da religião, factores estes que os monges construtores consideraram ao transformar o lugar e anunciar a sua existência na Terra. Esta investigação tem por objectivo explorar a noção de pegada existencial de ‘Somapura Mahavihara’, nas suas dimensões territoriais, funcionais, estruturais, sociais, culturais e nas hierarquias simbólicas das realizações humanas para clarificar a tipologia arquitectónica que deu forma a ‘Somapura Mahavihara’ durante a evolução da arquitectura Vihara. Este entendimento pretende combinar/cruzar o conhecimen¬to arqueológico com estudos arquitectónicos comparativos de Viharas na antiga região de Bengal, com o objectivo de definir a singularidade de ‘Somapura Mahavihara’. Neste estudo estudar-se-á também o confronto entre a dimensão religiosa e a artística (divino vs. humano), integrados na arquitectura de ‘Somapura Mahavihara’ em perfeita harmonia.