RESUMEN
The aim of this study is to validate a minimally invasive surgical procedure to harvest palate periosteum as a source of tissue for mesenchymal stromal/stem cells. We performed a standardized procedure to harvest the palate periosteum in ten subjects, which consisted of a 3 mm disposable punch and a Molt periosteal elevator to harvest a small full-thickness fragment of soft tissue at the hard palate area, between the upper bicuspids, 3 to 4 mm apical to the cement enamel junction. The one-third inner portion was fragmented, and following standard cell culture procedures, the adherent cells were cultured for three passages, after obtaining 70-90% confluence. Cell morphology analysis, flow cytometry analysis, and viability and osteogenic differentiation assays were performed. In all 10 cases, uneventful healing was observed, with no need for analgesic intake. The evaluation of cell morphology showed elongated spindle-shaped cells distributed in woven patterns. A high viability range was verified as well as an immunophenotype compatible with mesenchymal stem cell lineage. The differentiation assay showed the potential of the cells to differentiate into the osteogenic lineage. These results demonstrate that the minimally invasive proposed surgical technique is capable of supplying enough periosteum source tissue for stem cell culture and bone tissue engineering.
RESUMEN
Disaster victim identification is structured according to international recommendations on the attempt to optimize forensic logistics. The International Criminal Police Organization (INTERPOL) establishes primary and secondary methods for human identification. This study aimed to revisit the existing literature to address the forensic importance of tattoos. The scientific literature has shown advances in the forensic analyses of tattoos specially when it comes to the application of especial imaging techniques, namely photography with infrared light to visualize latent tattoo inks and cover-up tattoos, as well as the use of biochemical processing to distinguish components of the tattoo inks. Other relevant aspect is the fields dedicated to tattoo descriptions in software used worldwide for disaster victim identification, namely PlassData. Coding systems have been proposed as well to facilitate communication in the human identification process. The future of forensic analyses of tattoos is promising considering the increase of research in recent years. Forensic practice might benefit from it with more scientific evidence to support the utilization of tattoo analyses in casework
A identificação de vítimas de desastres em massa é estruturada de acordo com recomendações internacionais na tentativa de otimizar a logística forense. A INTERPOL (International Criminal Police Organization) estabelece métodos primários e secundários para identificação humana. Este estudo teve como objetivo revisitar a literatura existente para abordar a importância forense das tatuagens. A literatura científica tem mostrado avanços nas análises forenses de tatuagens, especialmente no que diz respeito à aplicação de técnicas especiais de imaginologia, como a fotografia com luz infravermelha para visualizar tintas latentes de tatuagens e tatuagens de cobertura, bem como a utilização de processamento bioquímico para distinguir componentes das tintas de tatuagem. Outro aspecto relevante são os campos dedicados à descrição de tatuagens em softwares utilizados mundialmente para identificação de vítimas de desastres em massa, como o PlassData. Sistemas de codificação também foram propostos para facilitar a comunicação no processo de identificação humana. O futuro das análises forenses de tatuagens é promissor considerando o aumento das pesquisas nos últimos anos. A prática forense pode beneficiar-se com mais evidências científicas para apoiar a utilização de análises de tatuagens na condução de casos periciais
RESUMEN
The aim of this study was to test whether lyophilized conditioned media from human dental pulp mesenchymal stem cell cultures promote the healing of critical-size defects created in the calvaria of rats. Prior to the surgical procedure, the medium in which dental pulp stem cells were cultured was frozen and lyophilized. After general anesthesia, an 8 mm diameter bone defect was created in the calvaria of twenty-four rats. The defects were filled with the following materials: xenograft alone (G1) or xenograft associated with lyophilized conditioned medium (G2). After 14 or 42 days, the animals were euthanized, and the specimens processed for histologic and immunohistochemical analysis. Bone formation at the center of the defect was observed only in the G2 at 42 days. At both timepoints, increased staining for VEGF, a marker for angiogenesis, was observed in G2. Consistent with this, at 14 days, G2 also had a higher number of blood vessels detected by immunostaining with an anti-CD34 antibody. In conclusion, conditioned media from human dental pulp mesenchymal stem cell cultures had a positive effect on the regenerative process in rat critical-size bone defects. Both the formation of bone and enhancement of vascularization were stimulated by the conditioned media.
RESUMEN
The growing demand for more efficient materials for medical applications brought together two previously distinct fields: medicine and engineering. Regenerative medicine has evolved with the engineering contributions to improve materials and devices for medical use. In this regard, graphene is one of the most promising materials for bone tissue engineering and its potential for bone repair has been studied by several research groups. The aim of this study is to conduct a scoping review including articles published in the last 12 years (from 2010 to 2022) that have used graphene and its derivatives (graphene oxide and reduced graphene) in preclinical studies for bone tissue regeneration, searching in PubMed/MEDLINE, Embase, Web of Science, Cochrane Central, and clinicaltrials.gov (to confirm no study has started with clinical trial). Boolean searches were performed using the defined key words "bone" and "graphene", and manuscript abstracts were uploaded to Rayyan, a web-tool for systematic and scoping reviews. This scoping review was conducted based on Joanna Briggs Institute Manual for Scoping Reviews and the report follows the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses - Extension for Scoping Reviews (PRISMA-ScR) statement. After the search protocol and application of the inclusion criteria, 77 studies were selected and evaluated by five blinded researchers. Most of the selected studies used composite materials associated with graphene and its derivatives to natural and synthetic polymers, bioglass, and others. Although a variety of graphene materials were analyzed in these studies, they all concluded that graphene, its derivatives, and its composites improve bone repair processes by increasing osteoconductivity, osteoinductivity, new bone formation, and angiogenesis. Thus, this systematic review opens up new opportunities for the development of novel strategies for bone tissue engineering with graphene.