A Bioinformatics Filtering Strategy for Identifying Radiation Response Biomarker Candidates

The number of biomarker candidates is often much larger than the number of clinical patient data points available, which motivates the use of a rational candidate variable filtering methodology. The goal of this paper is to apply such a bioinformatics filtering process to isolate a modest number (<10) of key interacting genes and their associated single nucleotide polymorphisms involved in radiation response, and to ultimately serve as a basis for using clinical datasets to identify new biomarkers. In step 1, we surveyed the literature on genetic and protein correlates to radiation response, in vivo or in vitro, across cellular, animal, and human studies. In step 2, we analyzed two publicly available microarray datasets and identified genes in which mRNA expression changed in response to radiation. Combining results from Step 1 and Step 2, we identified 20 genes that were common to all three sources. As a final step, a curated database of protein interactions was used to generate the most statistically reliable protein interaction network among any subset of the 20 genes resulting from Steps 1 and 2, resulting in identification of a small, tightly interacting network with 7 out of 20 input genes. We further ranked the genes in terms of likely importance, based on their location within the network using a graph-based scoring function. The resulting core interacting network provides an attractive set of genes likely to be important to radiation response

Estudo laboratorial do tempo de fechamento das alças e do grau de inclinação do canino, durante o procedimento de retração, empregando mecânica de arco segmentado Laboratorial study of loops closure time and degree of cuspid´s tipping, during the retraction phase, using segmented arch mechanics

OBJETIVO: avaliar o tempo de retração e o grau da inclinação sofrida pelo canino empregando três tipos de molas ortodônticas para retração - a alça em "T", a alça em "L" e a alça em forma de gota. MÉTODOS: foram utilizados três tipos de fio - aço inoxidável da marca comercial Morelli, aço inoxidável da marca comercial 3M Unitek e liga de beta-titânio da marca comercial Ormco; todos de calibre 0,019" x 0,025". A amostra resultante da combinação dos fatores mola e fio foi submetida à avaliação em modelo de typodont específico para essa finalidade. RESULTADOS: com relação ao tempo de fechamento das alças, verificou-se que um fechamento mais lento, e consequentemente com menor liberação de forças, foi obtido com o desenho de alça em "T" e, ainda, empregando-se a liga de beta-titânio para sua confecção. No que diz respeito à inclinação gerada pelas alças, as alças em forma de gota promoveram uma inclinação dentária maior do que as demais avaliadas. As alças em "T", por outro lado, mantiveram-se relacionadas estatisticamente aos menores valores de inclinação. Porém, quando se empregou o fio de aço inoxidável da marca comercial 3M Unitek para sua confecção, os três tipos de alça não apresentaram diferença estatisticamente significante. CONCLUSÃO: independentemente do desenho de alça empregado, aquelas construídas com liga de beta-titânio mantiveram-se relacionadas estatisticamente aos menores valores de inclinação observados para o elemento dentário movimentado.<br>OBJETIVE: Evaluate the cuspid's retraction time and tipping effects, after submitting it to three different orthodontic retraction loops: the "T" loop, the "boot" loop, and the "tear drop" loop. METHODS: It was used the following orthodontic wires: Morelli 0.019" x 0.025" stainless steel, 3M Unitek 0.019" x 0.025" stainless steel and Ormco 0.019" x 0.025" beta-titanium (TMA&trade;). The resulting sample from the combination of these variables was submitted to a test developed on a typodont simulator used specifically for this purpose. RESULTS: As the closure timing concerns, it was verified that a slower closure and therefore, a smaller releasing force system was achieved by the "T" loop design and still, by employing the beta-titanium alloy on its construction. As to the tipping effects generated by the retraction device, the "tear drop" loop caused greater tipping effects than the other loops evaluated. The "T" loop, on the other hand, showed itself statistically related to the lowest tipping numerical values. However, when the 3M Unitek stainless steel wire was used to produce the device, all of the types of loops evaluated were considered statistically similar. CONCLUSION: Regardless of the loop design, the ones built out of beta-titanium alloy kept them statistically related to the lowest tipping numerical values observed for the retracted dental element

Breathing and singing: objective characterization of breathing patterns in classical singers

Singing involves distinct respiratory kinematics (i.e. movements of rib cage and abdomen) to quiet breathing because of different demands on the respiratory system. Professional classical singers often advocate for the advantages of an active control of the abdomen on singing performance. This is presumed to prevent shortening of the diaphragm, elevate the rib cage, and thus promote efficient generation of subglottal pressure during phonation. However, few studies have investigated these patterns quantitatively and inter-subject variability has hindered the identification of stereotypical patterns of respiratory kinematics. Here, seven professional classical singers and four untrained individuals were assessed during quiet breathing, and when singing both a standard song and a piece of choice. Several parameters were extracted from respiratory kinematics and airflow, and principal component analysis was used to identify typical patterns of respiratory kinematics. No group differences were observed during quiet breathing. During singing, both groups adapted to rhythmical constraints with decreased time of inspiration and increased peak airflow. In contrast to untrained individuals, classical singers used greater percentage of abdominal contribution to lung volume during singing and greater asynchrony between movements of rib cage and abdomen. Classical singers substantially altered the coordination of rib cage and abdomen during singing from that used for quiet breathing. Despite variations between participants, principal component analysis revealed consistent pre-phonatory inward movements of the abdominal wall during singing. This contrasted with untrained individuals, who demonstrated synchronous respiratory movements during all tasks. The inward abdominal movements observed in classical singers elevates intra-abdominal pressure and may increase the length and the pressure-generating capacity of rib cage expiratory muscles for potential improvements in voice quality