995 resultados para Tissue Preservation
Resumo:
Aiming at time-spatial characterization of tissue temperature when ultrasound is applied for thermal therapeutic proposes two experiments were developed considering gel-based phantoms, one of them including an artificial blood vessel. The blood vessel was mimicking blood flow in a common carotid artery. For each experiment phantoms were heated by a therapeutic ultrasound (TU) device emitting different intensities (0.5, 1, 1.5, 1.8 W/cm2). Temperature was monitored by thermocouples and estimated through imaging ultrasound transducer's signals within specific special points inside the phantom. The temperature estimation procedure was based on temporal echo-shifts (TES), computed based on echo-shifts collected through image ultrasound (IU) transducer. Results show that TES is a reliable non-invasive method of temperature estimation, regardless the TU intensities applied. Presence of a pulsatile blood flow vessel in the focal point of TU transducer reduces thermal variation in more than 50%, also affecting the temperature variation in the surrounding area. In other words, vascularized tissues require longer ultrasound thermal therapeutic sessions or higher TU intensities and inclusion of IU in the therapeutic procedure enables non-invasive monitoring of temperature. © 2013 IEEE.
Resumo:
The identification of genes involved in signaling and regulatory pathways, and matrix formation is paramount to the better understanding of the complex mechanisms of bone formation and mineralization, and critical to the successful development of therapies for human skeletal disorders. To achieve this objective, in vitro cell systems derived from skeletal tissues and able to mineralize their extracellular matrix have been used to identify genes differentially expressed during mineralization and possibly new markers of bone and cartilage homeostasis. Using cell systems of fish origin and techniques such as suppression subtractive hybridization and microarray hybridization, three genes never associated with mechanisms of calcification were identified: the calcium binding protein S100-like, the short-chain dehydrogenase/reductase sdr-like and the betaine homocysteine S-methyltransferase bhmt3. Analysis of the spatial-temporal expression of these 3 genes by qPCR and in situ hybridization revealed: (1) the up-regulation of sdr-like transcript during in vitro mineralization of gilthead seabream cell lines and its specificity for calcified tissues and differentiating osteoblasts; (2) the up-regulation of S100-like and the down-regulation of bhmt3 during in vitro mineralization and the central role of both genes in cartilaginous tissues undergoing endo/perichondral mineralization in juvenile fish. While expression of S100-like and bhmt3 was restricted to calcified tissues, sdr-like transcript was also detected in soft tissues, in particular in tissues of the gastrointestinal tract. Functional analysis of gene promoters revealed the transcriptional regulation of the 3 genes by known regulators of osteoblast and chondrocyte differentiation/mineralization: RUNX2 and RAR (sdr-like), ETS1 (s100-like; bhmt3), SP1 and MEF2c (bhmt3). The evolutionary relationship of the different orthologs and paralogs identified within the scope of this work was also inferred from taxonomic and phylogenetic analyses and revealed novel protein subfamilies (S100-like and Sdr-like) and the explosive diversity of Bhmt family in particular fish groups (Neoteleostei). Altogether our results contribute with new data on SDR, S100 and BHMT proteins, evidencing for the first time the role for these three proteins in mechanisms of mineralization in fish and emphasized their potential as markers of mineralizing cartilage and bone in developing fish.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
The State Historic Preservation Office at the South Carolina Department of Archives and History publishes a monthly newsletter featuring agency programs and events, and highlights those of state and national preservation groups.
Resumo:
Tese de mestrado em Engenharia Biomédica e Biofísica, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2015
