Compostos de Cromo: Aulas experimentais contextualizadas para o Ensino Fundamental, realizadas numa escola pública de Belém-Pará.

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The influence of non-steroidal anti-inflammatory drugs and paracetamol used for pain control of orthodontic tooth movement: a systematic review

ABSTRACT The present study aimed to perform a systematic literature review to determine if there is a non-steroidal anti-inflammatory drug (NSAID) that interferes less within tooth movement. This research was performed according to the PRISMA statement. Articles were searched in eight electronic databases (PubMed, Scopus, Embase, Web of Science, LILACS, SciELO, Google Scholar, and Open Grey). Only experimental studies on male Wistar rats were selected, which included experiments related to the influence of NSAIDs on orthodontic movement. Studies in animals with pathological conditions, literature review articles, letters to the editor and/or editorials, case reports, abstracts, books, and book chapters were excluded. Each of the steps of this systematic literature review was performed by two examiners independently. Results: the total sample consisted of 505 articles, from which 6 studies were eligible after a qualitative analysis. From the drugs assessed, paracetamol was unanimous for not interfering within orthodontic movement when compared to the control group. However, drugs such as aspirin, ibuprofen, sodium diclofenac, and selective cyclooxygenase-2 inhibitors caused a reduction in tooth movement when compared to the control group. Conclusion: paracetamol could be considered the drug of choice for pain relief because it interferes less within tooth movement

Physical, Chemical, and Immunohistochemical Investigation of the Damage to Salivary Glands in a Model of Intoxication with Aluminium Citrate

Aluminum absorption leads to deposits in several tissues. In this study, we have investigated, to our knowledge for the first time, aluminum deposition in the salivary glands in addition to the resultant cellular changes in the parotid and submandibular salivary glands in a model of chronic intoxication with aluminum citrate in rats. Aluminum deposits were observed in the parotid and submandibular glands. Immunohistochemical evaluation of cytokeratin-18 revealed a decreased expression in the parotid gland with no changes in the submandibular gland. A decreased expression of α-smooth muscle actin was observed in the myoepithelial cells of both glands. The expression of metallothionein I and II (MT-I/II), a group of metal-binding proteins, which are useful indicators for detecting physiological responses to metal exposure, was higher in both glands. In conclusion, we have shown that at a certain time and quantity of dosage, aluminum citrate promotes aluminum deposition in the parotid and submandibular glands, leads to an increased expression of MT-I/II in both the glands, damages the cytoskeleton of the myoepithelial cells in both glands, and damages the cytoskeleton of the acinar/ductal cells of the parotid glands, with the submandibular glands showing resistance to the toxicity of the latter

Characterization, agricultural potential, and perspectives for the management of light soils in Brazil

Os solos leves ocupam cerca de 8% do território brasileiro e são epecialmente expressivos na nova e na última fronteira agrícola do país: a região de Matopiba, nos estados do Maranhão, do Tocantins, do Piauí e da Bahia, onde representam 20% da área. Esses solos enquadram-se nas classes texturais areia e areia franca ou francoarenosa, até a profundidade de 0,75 m ou mais, e são representados principalmente pelos Neossolos Quartzarênicos e, em parte, por Latossolos e Argissolos. O entendimento do funcionamento desses solos depende do estabelecimento de critérios distintivos sobre: dinâmica da matéria orgânica; teor e mineralogia da fração argila; teores de areia grossa e de areia total, em relação aos de areia fina; diâmetro médio da fração areia; e capacidade de retenção de água. Esses critérios podem contribuir para o zoneamento e para o manejo conservacionista e da fertilidade dos solos leves, bem como para estimação de seu potencial agrícola. Sistemas integrados de produção, como os de integração lavoura-pecuária e lavoura-pecuária-floresta, além do plantio direto com rotação de culturas, dos plantios florestais mistos com espécies leguminosas, e do uso de adubos verdes e cultivos de cobertura, são relevantes para o manejo adequado desses solos. O objetivo deste artigo de revisão foi caracterizar os solos leves e apontar os principais desafios em relação a seu potencial agrícola, a seu manejo e conservação e sua fertilidade, frente à expansão e à consolidação da nova fronteira agrícola.Light soils occupy 8% of the Brazilian territory and are especially expressive in the new and last agricultural frontier in Brazil: the Matopiba region – in the states of Maranhão, Tocantins, Piauí, and Bahia –, where they represent 20% of the area. These soils fit into the textural classes of sand, loamy sand, and sandy loam, down to 0.75-m soil depth or deeper, and they are mainly represented by Entisols (Quartzipsamments), and partly by Oxisols and Ultisols. The understanding of soil functioning depends on the establishment of distinguishing criteria for: organic matter dynamics; content and mineralogy of the clay fraction; coarse sand and total sand contents, in relation to those of fine sand; mean diameter of the sand fraction; and water retention capacity. These criteria can contribute for the zoning and for the conservationist and fertility management of light soils, as well as for the estimation of their agricultural potential. Integrated production systems, such as, crop-livestock and crop-livestock-forestry integration, besides no-tillage with crop rotation, mixed forestry planting with legumes, and the use of green manure and cover crops, are relevant for the proper management of these soils. The objective of this review was to characterize light soils and to highlight the main challenges regarding their agricultural potential and their conservation and fertility managements, in face of the expansion and consolidation of the new Brazilian agricultural frontier