RESUMO
ABSTRACT After breast cancer surgery, women might develop musculoskeletal impairments that affect movements of the upper limbs and reduce the quality of life. The objective of this research was to analyze the effect of the unilateral breast cancer surgery on the kinematics of the shoulder and the electrical activity of the upper trapezius, middle deltoid and pectoralis major muscles. Eight right-handed female participants, mean age 46.5 ± 5.45 years and mean body mass 71.21 ± 13.33 kg, with unilateral breast cancer surgery, without breast reconstruction and without lymphedema symptoms were included in the research. Flexion-extension and abduction-adduction movements of the shoulder were evaluated with infrared cameras and the electrical activity was measured using surface electromyography. The statistical analysis of the direction angles showed a significant reduction of the flexion-extension and abduction-adduction movements in the affected side in most of the participants (p<0.05). The muscle electrical activity did not present a significant difference between the two sides for the flexion-extension and abduction-adduction movements (p>0.05). The results suggest that the surgical procedure could compromise the range of motion of the affected side. Furthermore, this research contributes to clarify the effect of the surgical procedure in the range of motion of the upper limbs.
RESUMEN Después de la cirugía de cáncer de mama, las mujeres pueden desarrollar deficiencias musculoesqueléticas que afectan los movimientos de las extremidades superiores y reducen la calidad de vida. El objetivo de esta investigación fue analizar el efecto de la cirugía unilateral del cáncer de mama sobre la cinemática del hombro y la actividad eléctrica de los músculos trapecio superior, deltoides medio y pectoral mayor. Se incluyeron ocho participantes diestras, edad promedio 46.5 ± 5.45 años y masa promedio 71.21 ± 13.33 kg, con cirugía de cáncer de mama unilateral, sin reconstrucción mamaria y sin síntomas de linfedema. Los movimientos de flexión-extensión y abducción-aducción del hombro se evaluaron con cámaras infrarrojas y se midió la actividad eléctrica mediante electromiografía de superficie. El análisis estadístico de los ángulos de dirección mostró una reducción significativa del movimiento de flexión-extensión y abducción-aducción en el lado afectado en la mayoría de las participantes (p<0.05). La actividad eléctrica muscular no presentó diferencia significativa entre los dos lados para los movimientos de flexión-extensión y abducción-aducción (p>0.05). Los resultados sugieren que el procedimiento quirúrgico podría comprometer el rango de movimiento del lado afectado. Además, esta investigación contribuye a esclarecer el efecto del procedimiento quirúrgico en el rango de movimiento de los miembros superiores.
RESUMO
BACKGROUND: Scientific activity for 3D bioprinting has increased over the past years focusing mainly on fully functional biological constructs to overcome issues related to organ transplants. This research performs a scientometric analysis on bioprinting based on a competitive technology intelligence (CTI) cycle, which assesses scientific documents to establish the publication rate of science and technology in terms of institutions, patents or journals. Although analyses of publications can be observed in the literature, the identification of the most influential authors and affiliations has not been addressed. This study involves the analysis of authors and affiliations, and their interactions in a global framework. We use network collaboration maps and Betweenness Centrality (BC) to identify of the most prominent actors in bioprinting, enhancing the CTI analysis. RESULTS: 2088 documents were retrieved from Scopus database from 2007 to 2017, disclosing an exponential growth with an average publication increase of 17.5% per year. A threshold of five articles with ten or more cites was established for authors, while the same number of articles but cited five or more times was set for affiliations. The author with more publications was Atala A. (36 papers and a BC = 370.9), followed by Khademhosseini A. (30 documents and a BC = 2104.7), and Mironov (30 documents and BC = 2754.9). In addition, a small correlation was observed between the number of collaborations and the number of publications. Furthermore, 1760 institutions with a median of 10 publications were found, but only 20 within the established threshold. 30% of the 20 institutions had an external collaboration, and institutions located in and close to the life science cluster in Massachusetts showed a strong cooperation. The institution with more publications was the Harvard Medical School, 61 publications, followed by the Brigham and Women's hospital, 46 papers, and the Massachusetts Institute of Technology with 37 documents. CONCLUSIONS: Network map analysis and BC allowed the identification of the most influential authors working on bioprinting and the collaboration between institutions was found limited. This analysis of authors and affiliations and their collaborations offer valuable information for the identification of potential associations for bioprinting researches and stakeholders.
Assuntos
Bioimpressão/métodos , Publicações , Animais , Bibliometria , Pesquisa Biomédica , Bases de Dados Factuais , Colaboração IntersetorialRESUMO
A scientometric analysis as part of a Competitive Technology Intelligence methodology was used to determine the main research efforts in 3D bioprinting. Papers from Scopus and Web of Science (WoS) published between 2000 and 2017 were analysed. A network map of the most frequently occurring keywords in these articles was created, and their average publication year (APY) was determined. The analysis focused on the most relevant keywords that occurred at least five times. A total of 1,759 keywords were obtained, and a co-occurrence analysis was developed for APYs with more keywords: 2011-2016. The results indicated that Polylactic Acid (PLA) is the material used most often. Applications mainly focused on bone tissue engineering and regeneration. The most frequently used technique was inkjet printing, and the main cell sources were Mesenchymal Stem Cells (MSC). From a general perspective, 'Treatment' and 'Bioink' were the most frequent keywords. The former was mainly related to cancer, regenerative medicine, and MSC and the latter, to multicellular spheroid deposition and the use of hydrogels like GelMA (gelatin methacryloyl). This analysis provides insights to stakeholders involved in 3D bioprinting research and development who need to keep abreast of scientific progress in the field.
RESUMO
La causa más común de falla en prótesis coxofemorales es el aflojamiento entre los componentes que conforman el sistema, de manera específica la copa acetabular y la cabeza femoral. En esta investigación se presenta un análisis tribológico del desgaste en los componentes mencionados, ya que cuando las superficies en contacto se desgastan, la funcionalidad mecánica del sistema se compromete, debido al cambio de geometría de los mismos, dando como resultado un juego mecánico entre la copa y la cabeza. Los materiales considerados en este estudio son el polietileno de ultra elevado peso molecular (UHMWPE, por sus siglas en inglés) para la copa acetabular, y acero inoxidable 316L para la cabeza femoral. Esta combinación de materiales representa hoy en día la recomendación más usual por parte de los cirujanos para pacientes de la tercera edad. La tasa anual de desgaste se determinó de manera experimental y se cuantificó la cantidad de material desprendido durante el contacto. Se establecieron las condiciones de carga de forma analítica, considerando las que actúan sobre la cabeza femoral a lo largo del área de desgaste durante la marcha humana. Posteriormente, se realizó el análisis experimental de desgaste utilizando una máquina tribológica de configuración perno-sobre-disco (pin-on-disk), diseñada de manera específica para este estudio. Las pruebas para determinar la pérdida volumétrica de los componentes se realizaron bajo tres condiciones de operación: en seco, lubricada con agua destilada y lubricada con suero bovino. El marco experimental considerado consistió en pernos de UHMWPE sobre discos de acero inoxidable 316l simulando el desgaste equivalente a diez años de uso de la prótesis. Finalmente, de los resultados obtenidos se puede establecer que el desgaste y la cantidad de partículas desprendidas disminuyen considerablemente cuando se utiliza suero bovino como lubricante para replicar las condiciones reales de operación del sistema...
The most common cause of failure in coxofemoral prostheses is the loosening between the components of the system, namely the acetabular cup and the femoral head. In this work a tribologic analysis of wear suffered in the components is presented, due to when the surfaces in contact are worn, the mechanical function of the system is compromised as the wearing implies a change in the geometry of the components, thus in their dimensions, resulting on a looseness between the cup and the head. The materials considered in this study are Ultra High Molecular Weight Polyethylene (UHMWPE) for the cup and 316L Stainless Steel for the femoral head, which represent the surgeons choice for elderly patients. The annual wearing rate between these components was experimentally determined, as well as the amount of debris produced during contact. Firstly, the loading conditions were determined analytically considering those acting on the femoral head taking into consideration the wearing area during human walk. Secondly, the experimental analysis consisted in wearing tests using a tribology pin-on-disk machine, specifically built for this study. The tests to determine the volumetric loss of the components were performed under three different operational conditions: dry, lubricated with bovine serum and lubricated with destilated water. The experimental set up consisted on UHMWPE pins and 316L Stainless steel discs simulating the equivalent wear of ten years of usage of the prostheses. Lastly, the obtained results proved that using the bovine serum as lubricant the wear and debris of the components was significantly reduced when compared with other cases, being the dry scenario where more damage was produced. It is important to point out that the bovine serum was chosen to simulate the synovial fluid in which the system is embedded.