Embryonic stem cells in scaffold-free three-dimensional cell culture: osteogenic differentiation and bone generation

Extracorporeal formation of mineralized bone-like tissue is still an unsolved challenge in tissue engineering. Embryonic stem cells may open up new therapeutic options for the future and should be an interesting model for the analysis of fetal organogenesis. Here we describe a technique for culturing embryonic stem cells (ESCs) in the absence of artificial scaffolds which generated mineralized miromasses. Embryonic stem cells were harvested and osteogenic differentiation was stimulated by the addition of dexamethasone, ascorbic acid, and ß-glycerolphosphate (DAG). After three days of cultivation microspheres were formed. These spherical three-dimensional cell units showed a peripheral zone consisting of densely packed cell layers surrounded by minerals that were embedded in the extracellular matrix. Alizarine red staining confirmed evidence of mineralization after 10 days of DAG stimulation in the stimulated but not in the control group. Transmission electron microscopy demonstrated scorching crystallites and collagenous fibrils as early indication of bone formation. These extracellular structures resembled hydroxyl apatite-like crystals as demonstrated by distinct diffraction patterns using electron diffraction analysis. The micromass culture technique is an appropriate model to form three-dimensional bone-like micro-units without the need for an underlying scaffold. Further studies will have to show whether the technique is applicable also to pluripotent stem cells of different origin

Virtual learning object for the simulated evaluation of acute pain in nursing students

This study aimed to evaluate the results of the application of a virtual learning object for the simulated evaluation of acute pain in the learning of undergraduate nursing students and to verify the opinions of the students regarding the quality of the technology. This was a quasi-experimental, non-randomized, before and after study performed with 14 students in the seventh phase of the undergraduate nursing course of the Federal University of Santa Catarina. The pre (8.84) and post-test (9.31) means revealed significant differences in learning after the intervention (p=0.03). In the qualitative evaluation the flexibility of access, access independent of time/place, freedom to decide the best learning route and the similarity with reality were highlighted. It constitutes a promising educational tool, an interactive experience, similar to reality, dynamic and constructive learning. The application of the technology has brought positive results for learning about pain evaluation, contributing to fill the gap in the teaching of the thematic.El objetivo del estudio fue evaluar los resultados de la aplicación de un objeto virtual de aprendizaje para evaluación simulada de dolor agudo en el aprendizaje de estudiantes de graduación en enfermería y verificar su opinión sobre la calidad de la tecnología. Se trata de un estudio casi experimental, no aleatorio, del tipo antes y después, realizado con 14 estudiantes de la séptima fase de la graduación en enfermería de la Universidad Federal de Santa Catarina. Los promedios de la prueba, antes (8,84) y después (9,31), revelaron diferencia significativa en el aprendizaje después de la intervención (p=0.03). En la evaluación cualitativa se destacaron la flexibilidad de acceso, el acceso independiente de tiempo/lugar, libertad para decidir el mejor curso de aprendizaje y la semejanza con la realidad. Constituye una promisora herramienta educacional, una experiencia interactiva, semejante a la realidad, dinámica y constructiva de aprendizaje. La aplicación de la tecnología presentó resultados positivos para el aprendizaje de la evaluación del dolor, contribuyendo para llenar un vacío en la enseñanza de la temática.O objetivo do estudo foi avaliar os resultados da aplicação de um objeto virtual de aprendizagem para avaliação simulada da dor aguda na aprendizagem de estudantes de graduação em enfermagem e verificar sua opinião sobre a qualidade da tecnologia. Trata-se de estudo quase experimental, não randomizado, do tipo antes e depois, realizado com 14 estudantes da sétima fase da graduação em enfermagem da Universidade Federal de Santa Catarina. As médias de pré (8,84) e pós-teste (9,31) revelaram diferença significativa na aprendizagem, após intervenção (p=0,03). Na avaliação qualitativa, destacaram-se a flexibilidade de acesso, o acesso independente de tempo/lugar, liberdade para decidir o melhor percurso de aprendizagem e a semelhança com a realidade. Constitui promissora ferramenta educacional, uma experiência interativa, semelhante à realidade, dinâmica e construtiva de aprendizagem. A aplicação da tecnologia trouxe resultados positivos para a aprendizagem da avaliação da dor, contribuindo para o preenchimento da lacuna no ensino da temática

Role of GP82 in the Selective Binding to Gastric Mucin during Oral Infection with Trypanosoma cruzi

Oral infection by Trypanosoma cruzi has been the primary cause of recent outbreaks of acute Chagas' diseases. This route of infection may involve selective binding of the metacyclic trypomastigote surface molecule gp82 to gastric mucin as a first step towards invasion of the gastric mucosal epithelium and subsequent systemic infection. Here we addressed that question by performing in vitro and in vivo experiments. A recombinant protein containing the complete gp82 sequence (J18), a construct lacking the gp82 central domain (J18*), and 20-mer synthetic peptides based on the gp82 central domain, were used for gastric mucin binding and HeLa cell invasion assays, or for in vivo experiments. Metacyclic trypomastigotes and J18 bound to gastric mucin whereas J18* failed to bind. Parasite or J18 binding to submaxillary mucin was negligible. HeLa cell invasion by metacyclic forms was not affected by gastric mucin but was inhibited in the presence of submaxillary mucin. Of peptides tested for inhibition of J18 binding to gastric mucin, the inhibitory peptide p7 markedly reduced parasite invasion of HeLa cells in the presence of gastric mucin. Peptide p7*, with the same composition as p7 but with a scrambled sequence, had no effect. Mice fed with peptide p7 before oral infection with metacyclic forms developed lower parasitemias than mice fed with peptide p7*. Our results indicate that selective binding of gp82 to gastric mucin may direct T. cruzi metacyclic trypomastigotes to stomach mucosal epithelium in oral infection

Access to Adequate Outpatient Depression Care for Mothers in the USA: A Nationally Representative Population-Based Study

Maternal depression is often untreated, resulting in serious consequences for mothers and their children. Factors associated with receipt of adequate treatment for depression were examined in a population-based sample of 2,130 mothers in the USA with depression using data from the 1996–2005 Medical Expenditure Panel Survey. Chi-squared analyses were used to evaluate differences in sociodemographic and health characteristics by maternal depression treatment status (none, some, and adequate). Multivariate regression was used to model the odds of receiving some or adequate treatment, compared to none. Results indicated that only 34.8% of mothers in the USA with depression received adequate treatment. Mothers not in the paid workforce and those with health insurance were more likely to receive treatment, while minority mothers and those with less education were less likely to receive treatment. Understanding disparities in receipt of adequate treatment is critical to designing effective interventions, reducing treatment inequities, and ultimately improving the mental health and health of mothers and their families