Effect of uncaria tomentosa extract on purinergic enzyme activities in lymphocytes of rats submitted to experimental adjuvant arthritis model

Background: Considering that adjuvant arthritis is an experimental model of arthritis widely used for preclinical testing of numerous anti-arthritic agents, which were taken by a large number of patients worldwide, it is of great interest to investigate the therapeutic action of compounds with anti-inflammatory properties, such as Uncaria tomentosa extract. Moreover, there are no studies demonstrating the effect of U. tomentosa on the metabolism of adenine nucleotides published so far. Thus, the purpose of the present study is to investigate the effects of U. tomentosa extract on E-NTPDase and E-ADA activities in lymphocytes of Complete Freund’s Adjuvant (CFA) arthritis induced rats. Methods: To evaluate the effect of U. tomentosa extract on the activity of E-NTPDase and ADA in lymphocytes, the rats were submitted to an experimental adjuvant arthritis model. Peripheral lymphocytes were isolated and E-NTPDase and E-ADA activities were determined. Data were analyzed by a one- or two-way ANOVA. Post hoc analyses were carried out by the Student-Newman-Keuls (SNK) Multiple Comparison Test. Results: E-NTPDase activity was increased in arthritic untreated. Arthritic rats which received U. tomentosa extract, presented similar results to the control group. However, results obtained for adenosine hydrolysis by E-ADA were not altered in arthritic rats. U. tomentosa extract did not alter E-NTPDase and E-ADA activity in healthy animals. Conclusions: The present investigation supports the hypothesis that the increased E-NTPDase activity verified in arthritic rats might be an attempt to maintain basal levels of ATP and ADP in the extracellular medium, since the arthritis induction causes tissue damage and, consequently, large amounts of ATP are released into this milieu. Also, it highlights the possibility to use U. tomentosa extract as an adjuvant to treat arthritis

Effect of uncaria tomentosa extract on purinergic enzyme activities in lymphocytes of rats submitted to experimental adjuvant arthritis model

Background: Considering that adjuvant arthritis is an experimental model of arthritis widely used for preclinical testing of numerous anti-arthritic agents, which were taken by a large number of patients worldwide, it is of great interest to investigate the therapeutic action of compounds with anti-inflammatory properties, such as Uncaria tomentosa extract. Moreover, there are no studies demonstrating the effect of U. tomentosa on the metabolism of adenine nucleotides published so far. Thus, the purpose of the present study is to investigate the effects of U. tomentosa extract on E-NTPDase and E-ADA activities in lymphocytes of Complete Freund’s Adjuvant (CFA) arthritis induced rats. Methods: To evaluate the effect of U. tomentosa extract on the activity of E-NTPDase and ADA in lymphocytes, the rats were submitted to an experimental adjuvant arthritis model. Peripheral lymphocytes were isolated and E-NTPDase and E-ADA activities were determined. Data were analyzed by a one- or two-way ANOVA. Post hoc analyses were carried out by the Student-Newman-Keuls (SNK) Multiple Comparison Test. Results: E-NTPDase activity was increased in arthritic untreated. Arthritic rats which received U. tomentosa extract, presented similar results to the control group. However, results obtained for adenosine hydrolysis by E-ADA were not altered in arthritic rats. U. tomentosa extract did not alter E-NTPDase and E-ADA activity in healthy animals. Conclusions: The present investigation supports the hypothesis that the increased E-NTPDase activity verified in arthritic rats might be an attempt to maintain basal levels of ATP and ADP in the extracellular medium, since the arthritis induction causes tissue damage and, consequently, large amounts of ATP are released into this milieu. Also, it highlights the possibility to use U. tomentosa extract as an adjuvant to treat arthritis

Thick collagen-based 3D matrices including growth factors to induce neurite outgrowth

Designing synthetic microenvironments for cellular investigations is a very active area of research at the crossroads of cell biology and materials science. The present work describes the design and functionalization of a three-dimensional (3D) culture support dedicated to the study of neurite outgrowth from neural cells. It is based on a dense self-assembled collagen matrix stabilized by 100-nm wide interconnected native fibrils without chemical crosslinking. The matrices were made suitable for cell manipulation and direct observation in confocal microscopy by anchoring them to traditional glass supports with a calibrated thickness of ∼50 μm. The matrix composition can be readily adapted to specific neural cell types, notably by incorporating appropriate neurotrophic growth factors. Both PC-12 and SH-SY5Y lines respond to growth factors (nerve growth factor and brain-derived neurotrophic factor, respectively) impregnated and slowly released from the support. Significant neurite outgrowth is reported for a large proportion of cells, up to 66% for PC12 and 49% for SH-SY5Y. It is also shown that both growth factors can be chemically conjugated (EDC/NHS) throughout the matrix and yield similar proportions of cells with longer neurites (61% and 52%, respectively). Finally, neurite outgrowth was observed over several tens of microns within the 3D matrix, with both diffusing and immobilized growth factors

Diários de uma professora estagiária: problematizando o saber da experiência nos estágios supervisionados em Ciências da Natureza

Through this article, we discuss the experience which emerged during the teaching practice held in Supervised Internships II and III of the Nature Sciences program – a teacher training program, Federal University of Pampa, Uruguaiana Campus. This qualitative study was based on the classroom diary as a research instrument presenting as corpus of analysis the diaries produced by the internship teacher after each taught class in elementary and high school. The class diaries are understood from the perspective of Zabalza (2004), who discusses them as a powerful tool to think about teaching practice. The class diaries were analyzed from the perspective of finding the situations which are presented as experiences from the understanding of Larrosa (2002), that is, something which touches, mobilizes and makes us think. In the analysis of the class diaries two moments were evident in the school context. One that presents motivated students who excite the teacher's satisfaction in planning and delivering their classes. Another one that demands greater dedication from the teacher in which the students are undisciplined and present a lack of motivation to learn. In addition, it was evident in the analysis of the class diaries the need of the teacher when going through issues which do not depend on their teaching practice, but which interferes on that, such as infrastructure and school organization. Finally, we defend the importance of using journals, not only as a way of recording the events of their daily lives, but also as a research tool for the teacher to reflect their own practice and qualify their teacher training.Neste artigo problematizamos a experiência que emergiu durante a prática docente dos Estágios Supervisionados II e III do curso de Ciências da Natureza – Licenciatura, da Universidade Federal do Pampa, Campus Uruguaiana. Este estudo de caráter qualitativo valeu-se do diário de aula como instrumento de pesquisa tendo como corpus de análise os diários produzidos pela professora estagiária após cada aula ministrada no Ensino Fundamental e no Ensino Médio. Os diários de aula são compreendidos na perspectiva de Zabalza (2004), que discute os mesmos como ferramenta potente para pensar a prática docente. Os diários de aula foram analisados na perspectiva de encontrar as situações que se configuram em experiências a partir do entendimento de Larrosa (2002), ou seja, algo que nos toca, nos mobiliza e nos faz pensar. Na análise dos diários de aula ficaram evidentes dois momentos no contexto escolar. Um que apresenta alunos/as motivados/as que despertam a satisfação do/a professor/a ao planejar e ministrar suas aulas. Outro que exige uma dedicação maior do/a professor/a no qual os/as alunos/as são indisciplinados/as e não apresentam motivação para aprender. Além disso, ficou evidente na análise dos diários de aula a necessidade do/a professor/a deparar-se com questões que não dependem da sua prática docente, mas que interferem nela, como a infraestrutura e a organização escolar. Por fim, defendemos a importância do uso dos diários, não apenas como uma forma de registrar os acontecimentos do seu cotidiano, mas também como uma ferramenta de pesquisa para o/a professor/a refletir sua própria prática e qualificar a sua formação docente