Effects ot stretching on the extracellular matrix on the calcaneal tendon of rats

Orientador: Edson Rosa PimentelDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: Os tendões servem para realizar a transferência de força dos músculos para os ossos, sendo capazes de suportar altas forças de tensão. Muitos trabalhos descreveram alterações nas propriedades estruturais, bioquímicas e biomecânicas dos tendões de animais que foram submetidos a exercícios prolongados, porém pouco se sabe sobre o que ocorre no tendão que passa por um processo de alongamento, um procedimento bastante comum em academias e clínicas de Fisioterapia. Assim, nosso trabalho teve como objetivo avaliar os aspectos morfológicos e bioquímicos dos tendões de ratos submetidos ao alongamento três e cinco vezes por semana. Os ratos tiveram seus músculos alongados por um período de 30 segundos intercalados com 30 segundos de relaxamento, com 10 repetições, 3 e 5 vezes por semana durante 21 dias. Os tendões foram removidos e utilizados para os procedimentos de morfologia e de bioquímica. Os tendões também foram submetidos ao ensaio mecânico sob tração a fim de avaliar suas propriedades biomecânicas. Nos cortes corados com AT, na entese dos tendões dos grupos alongados, observou-se um aumento na quantidade de células com morfologia arredondada. Já na região próxima à entese pode ser observado metacromasia mais intensa nos grupos alongados. Observações feitas nos cortes corados com HE, nas regiões de tensão, mostraram que as células apresentaram-se mais alinhadas. Nos grupos alongados, em ambas regiões ocorreu aumento na quantidade de células. Nos cortes que foram submetidos à Reação de Von Kossa, observou-se uma região calcificada em todos os grupos, porém esta apresentou uma MEC mais densa nos tendões dos grupos alongados três e cinco vezes. Análise do gel de SDS-PAGE revelou uma maior quantidade de colágeno nos grupos alongados e a presença do componente de 65 kDa nas regiões de tensão e compressão em todos os grupos. A quantidade de proteínas, de glicosaminoglicanos e de hidroxiprolina também foi superior nos animais alongados. O gel de agarose revelou a presença de dermatam sulfato nas regiões de tensão e de compressão e de condroitim sulfato somente nesta última. Durante o ensaio mecânico, os tendões dos grupos alongados suportaram valores de tensão máxima superiores, com deslocamentos semelhantes, sugerindo que estes tendões são mais resistentes à ruptura. Esses resultados mostraram que o estímulo do alongamento acarretou modificações nas características estruturais, bioquímicas e biomecânicas, confirmando o caráter adaptativo do tendão em resposta à aplicação dos procedimentos de alongamentoAbstract: The tendons are structures that transmit forces from the muscles to the bone, and are capable of supporting high tensile strenghts. Many studies have shown alterations in tendons of animals submitted to strenuous exercises, however, just a little is known about what happens in tendons when they are under a stretching program, a common procedure in academies and phisiotherapy institutes. So our objective was to evaluate the morphological, biochemical and biomechanical aspects of tendons submitted to stretching exercises. Rats had their muscles stretched for a period of 30 seconds with 30 seconds of resting, with 10 repetitions, three and five times a week during 21 days. The tendons were used for morphological and biochemical procedures. They were also submitted to mechanical tensile strain test and their mechanical properties were evaluated. Analysis of AT stained sections of enthesis from stretched tendons, showed a high amount of rounded cells. In the region next to enthesis, which passes close to the calcaneous, the metachromasy was more intense in stretched groups. In the tension region, in the HE stained sections, it was found a larger alignment of the cells in the stretched group. In both regions occurred an increase on the amount of cells. In the sections submitted to Von Kossa reaction, was observed, a calcified region in all groups, but the extracellular matrix were denser in stretched ones. Analysis of SDS-Page showed a high amount of collagen and the presence of a polidisperse component of 65 kDa in the tension and compression regions in all groups. The amount of proteins, glycosaminoglycans and hydroxiproline was higher in the tendons of three and five times stretched groups. The agarose gel revealed the presence of dermatan sulfate in the tension and compression regions and chondroitin sulfate only in this last one. During the mechanical tensile strain test, the stretched tendon supported high values of maximum stress with the same strain, when compared to the control group, suggesting that the stretched tendons were more resistant to the failure. These results show that the stimulus of stretching leads to alterations in the structural, biochemical and biomechanical characteristics, confirming the adaptative character of tendons, in response to the application of stretching exercisesMestradoBiologia CelularMestre em Biologia Celular e Estrutura

Efeito do consumo de álcool no suporte ósseo periodontal em periodontite experimental em ratos

OBJECTIVE: The aim of this study was to evaluate the effect of the alcohol consumption on the periodontal bone support (PBS) in experimental periodontitis in rats. MATERIALS AND METHODS: Sixty-three male rats were divided into seven groups: G1 (control); G2 (10% ethanol); G3 (nutritional control of G2); G4 (20% ethanol); G5 (nutritional control of G4); G6 (30% ethanol) and G7 (nutritional control of G6). The groups G3, G5 and G7 received controlled diets with equivalent caloric amounts to those consumed in G2, G4 and G6 respectively, with the ethanol replaced by sucrose. After anesthesia, ligatures were installed around the mandibular first molar, leaving the contralateral teeth unligated. After 8 weeks, the rats were killed and their mandibles were radiographed to measure the percentage of PBS on the distal aspect. RESULTS: The intragroup analyses showed that presence of ligatures induced periodontitis (pOBJETIVO: O propósito deste estudo foi avaliar o efeito do consumo de álcool sobre o suporte ósseo periodontal (SOP) em periodontite induzida por ligaduras em ratos. MATERIAIS E MÉTODOS: Sessenta e três ratos machos foram divididos em sete grupos: G1 (controle); G2 (álcool a 10%); G3 (controle nutricional de G2); G4 (álcool a 20%); G5 (controle nutricional de G4); G6 (álcool a 30%); G7 (controle nutricional de G6). Os grupos G3, G5 e G7 receberam dietas controladas com a mesma quantidade de calorias consumidas por G2, G4 e G6, respectivamente, com o etanol substituído por sacarose. Após anestesia foram instaladas ligaduras no primeiro molar inferior direito, permanecendo o dente contralateral sem ligadura. Após oito semanas, os ratos foram sacrificados e as mandíbulas radiografadas para medição do SOP na proximal distal. RESULTADOS: A análise intragrupo mostrou que a presença da ligadura foi capaz de induzir periodontite (

Impact of Oral Conditions and Subjective Factors on Academic Performance

Objective: To evaluate the influence of oral health clinical and non-clinical indicators on adolescents’ academic performance. Material and Methods: A longitudinal design was performed with a random sample of 1,134 12-year-old Brazilian adolescents. In 2012, the adolescents were clinically assessed by calibrated dentists and investigated about demographics, socioeconomic factors, dental service use, toothache, and verbal bullying related to oral condition via structured questionnaires. The contextual variable was obtained from the city’s official database. After two years, 771 adolescents were reassessed. The outcome adolescent’s academic performance (good or poor) was collected through official school’s register. Multilevel logistic regression analyses were performed to assess associated factors for adolescents’ academic performance. Results: Adolescents with toothache (OR 1.74; CI 95%: 1.05-2.89), who have been a victim of bullying (OR 2.23; CI 95%: 1.21-4.09), and were male (OR 1.92; CI 95%: 1.19-3.09) had a lower academic performance. On the other hand, adolescents whose mothers had higher educational levels (OR 1.79; CI 95%: 1.08-2.97) and belonged to higher-income households (OR 1.95; CI 95%: 1.18-3.23) had higher academic performance when compared to their peers. Conclusion: Adverse oral conditions, as well as subjective and socioeconomic factors, impacted on adolescents’ academic performance

Spatiotemporal distribution of the magnetotactic multicellular prokaryote Candidatus Magnetoglobus multicellularis in a Brazilian hypersaline lagoon and in microcosms

Candidatus Magnetoglobus multicellularis is an unusual morphotype of magnetotactic prokaryotes. These microorganisms are composed of a spherical assemblage of gram-negative prokaryotic cells capable of swimming as a unitaligned along a magnetic field. While they occur in many aquatic habitats around the world, high numbers of Ca. M. multicellularishave been detected in Araruama Lagoon, a large hypersaline lagoon near the city of Rio de Janeiro, in Brazil. Here,we report on the spatiotemporal distribution of one such population in sediments of Araruama Lagoon, including its annualdistribution and its abundance compared with the total bacterial community. In microcosm experiments, Ca. M. multicellulariswas unable to survive for more than 45 days: the population density gradually decreased coinciding with a shift to theupper layers of the sediment. Nonetheless, Ca. M. multicellularis was detected throughout the year in all sites studied. Changes in the population density seemed to be related to the input of organic matter as well as to salinity. The populationdensity of Ca. M. multicellularis did not correlate with the total bacterial counts; instead, changes in the microbial communitystructure altered their counts in the environment. [Int Microbiol 2012; 15(3):141-149

Agregado leve: uma alternativa sustentável para o reaproveitamento de resíduo de serragem no processo industrial

 A serragem gerada no processamento da madeira tanto em lojas moveleiras como na extração de árvores é um resíduo que possui diversas aplicações para reutilização, mas que, em muitos casos, ainda é descartado de forma irregular no meio ambiente, contaminando o solo, o ar e a água. A produção de agregado leve pode ser uma opção para o reaproveitamento dessa serragem. O agregado leve (AL) é uma opção de brita usada em construção civil com o objetivo de reduzir o peso da estrutura, melhorar o conforme térmico e acústico ou, ainda, como opção para locais onde a brita não está disponível. No Brasil e em quase todo o mundo existem argilas comuns disponíveis e que poderiam ser utilizadas na produção de agregado leve. O objetivo desta pesquisa foi produzir um AL para diferentes aplicações, entre elas como agregado para construção civil, tijolos e como elemento de adorno. Foram testadas formulações para a produção de agregado leve contendo argila ilita e serragem. Também, para efeito de comparação, foi adquirido um agregado leve comercial, e formulações feitas com argila e carvão mineral, argila e óleo combustível. Os corpos de prova foram produzidos por prensagem à pressão de 30 MPa, em formato cilíndrico com diâmetro de 19 mm e altura de 15 mm. Após a queima, os corpos de prova foram caracterizados por ensaios tecnológicos de absorção de água, densidade aparente, resistência à compressão, difração de raios X e análise química por fluorescência de raios X. Os resultados mostraram que a incorporação de serragem nas formulações pode ser uma alternativa para a produção de agregado leve, uma vez que se obtiveram alta resistência e baixa densidade em comparação com o agregado leve comercial e os produzidos com materiais não sustentáveis. Além disso, o uso da serragem contribuiu para a redução do impacto ambiental causado pelo descarte desnecessário de serragem e pela extração de recursos naturais, necessários para a produção de materiais de construção.Sawdust generated by wood processing, both in industries processing and in tree felling, is a waste that has several applications for reuse, but, in many cases, it is still discarded irregularly in the environment, contaminating the soil, air, and water. The production of lightweight aggregate (LWA) can be an option for the reuse of this sawdust. The LWA is a gravel solution used in civil construction with the objective of reducing the weight of the structure, improving thermal and acoustic compliance, or as an option for locations where gravel is not available. In Brazil, and in most parts of the world, there are common clays available that can be used in the LWA production. The aim of this research was to produce an LWA for different applications, among them, as aggregate for civil construction, bricks, and as an adornment element. Formulations were tested to produce LWA containing illitic clay and sawdust. In the same way, for comparison, a commercial LWA was purchased, and formulations were made with clay and coal, and clay and fuel oil. The specimens were produced by pressing at 30 MPa in a cylindrical shape with a diameter of 19 mm and a height of 15 mm. After firing, the specimens were characterized by technological tests of water absorption, bulk density, compressive strength, X-ray diffraction analysis, and chemistry by X-ray fluorescence. The results indicated that the incorporation of sawdust in the formulations can be an alternative to produce LWA, once it obtained high strength and low density, compared to commercial LWA and to that produced with unattractive materials. Furthermore, it may contribute to the reduction of environmental impact, resulting from the disposal of sawdust and the generation of natural resources, necessary to produce construction materials

Irrigation water salinity and silicon negatively interfere with the physiology and delay the flowering of ornamental sunflowers

Although silicon is considered a non-essential element for plants, its application can mitigate the harmful effects of salt stress. In this sense, the objective was to evaluate the physiological and flowering responses of ornamentalsunflower depending on the application of silicon and irrigation with saline water. The experiment was carried out in a greenhouse in a completely randomized design with six replications, in a 4 x 5 factorial scheme, referring to four electrical conductivities of irrigation water (ECw): 0.5; 1.5; 2.5 and 3.5 dS m-1 and silicon doses: 0, 50, 100, 150 and 200 mg L-1, with potassium silicate as the source. The following were evaluated: internal carbon concentration, transpiration, rate of liquid photosynthesis, instant efficiency of carboxylation, leaf indexes of chlorophyll a, b, chlorophyll a/b ratio, total chlorophyll, external and internal diameter of the chapter, number of petals, appearance of floral bud, beginning of flowering and full opening of the floral bud. Salinity negatively affects photosynthetic activity and flowering of ornamental sunflower plants, so that plants irrigated with saline water (3.5 dS m-1) delayed the appearance of the flower bud, the flowering index and the total opening of the floral button. The application of silicon in ornamental sunflower plants is not effective to mitigate the deleterious effects of salinity on the plant’s physiology. In addition, the addition of silicon is also not able to repair the losses in terms of flowering caused by salt stress in the species.Although silicon is considered a non-essential element for plants, its application can mitigate the harmful effects of salt stress. In this sense, the objective was to evaluate the physiological and flowering responses of ornamentalsunflower depending on the application of silicon and irrigation with saline water. The experiment was carried out in a greenhouse in a completely randomized design with six replications, in a 4 x 5 factorial scheme, referring to four electrical conductivities of irrigation water (ECw): 0.5; 1.5; 2.5 and 3.5 dS m-1 and silicon doses: 0, 50, 100, 150 and 200 mg L-1, with potassium silicate as the source. The following were evaluated: internal carbon concentration, transpiration, rate of liquid photosynthesis, instant efficiency of carboxylation, leaf indexes of chlorophyll a, b, chlorophyll a/b ratio, total chlorophyll, external and internal diameter of the chapter, number of petals, appearance of floral bud, beginning of flowering and full opening of the floral bud. Salinity negatively affects photosynthetic activity and flowering of ornamental sunflower plants, so that plants irrigated with saline water (3.5 dS m-1) delayed the appearance of the flower bud, the flowering index and the total opening of the floral button. The application of silicon in ornamental sunflower plants is not effective to mitigate the deleterious effects of salinity on the plant’s physiology. In addition, the addition of silicon is also not able to repair the losses in terms of flowering caused by salt stress in the species

Desempenho de cimentos de ionômero de vidro nacionais e importados utilizados no Tratamento Restaurador Atraumático (ART) frente à microinfiltração em molares decíduos

Buscando comparar o desempenho de 2 cimentos de ionômero de vidro (CIV) restauradores convencionais nacionais, mais acessíveis tanto financeiramente quanto por disponibilidade no mercado, ao desempenho de 2 CIV importados frente à microinfiltração, confeccionou-se preparos classe II com término cervical em esmalte em 40 molares decíduos hígidos. Vinte cavidades foram restauradas com os CIV nacionais (Vidrion® R e Vidrion® R Caps) e as demais com os importados (Fuji® IX e Fuji® IX GPFast), por um único operador. Os dentes foram impermeabilizados, imersos em azul de metileno 0,5% e seccionados mesio-distalmente. A microinfiltração foi avaliada por 3 examinadores calibrados, em microscópio estereoscópico, através de escores (0-3). Foram utilizados os testes estatísticos de Kruskall-Wallis e de Wilcoxon. Verificou-se altos índices de microinfiltração para todos os CIV: 59,5% das amostras restauradas com Vidrion® R ou Vidrion® R Caps e 83,4% das amostras restauradas com Fuji® IX ou Fuji® IX GPFast obtiveram o escore máximo (3). Os CIV nacionais apresentaram menos microinfiltração que os CIV importados, embora essa diferença só tenha sido significativa (p=0,003) entre os materiais encapsulados.With the aim of assessing the performance of Brazilian and imported glass ionomer cements (GIC) with regard to microleakage, 40 primary molars received two standard class II cavity preparations with margins in enamel. Twenty cavities were filled with Brazilian materials (Vidrion® R and Vidrion® R Caps) and the other 20 cavities were filled with imported materials (Fuji® IX and Fuji® IX GPFast capsule). All fillings were performed by a single operator according to the manufacturer's instructions. Teeth were immersed in 0.5% methylene blue and half-sectioned. Three independent calibrated examiners assessed microleakage using scores (0-3). Data were submitted to the Kruskal-Wallis statistical test and Wilcoxon analysis. High microleakage indexes were verified for all ionomer cements: 59.5% of the samples restored with Vidrion® R or Vidrion® R Caps and 83.4% of the samples restored with Fuji® IX or Fuji® IX GPFast capsule obtained the maximum score (3). The Brazilian ionomer cements presented less microleakage than imported cements, although this difference was only significant (p=0.003) among the encapsulated materials

Administration of a histone deacetylase inhibitor into the basolateral amygdala enhances memory consolidation, delays extinction, and increases hippocampal BDNF levels

Gene expression related to the formation and modification of memories is regulated epigenetically by chromatin remodeling through histone acetylation. Memory formation and extinction can be enhanced by treatment with inhibitors of histone deacetylases (HDACs). The basolateral amygdala (BLA) is a brain area critically involved in regulating memory for inhibitory avoidance (IA). However, previous studies have not examined the effects of HDAC inhibition in the amygdala on memory for IA. Here we show that infusion of an HDAC inhibitor (HDACi), trichostatin A (TSA), into the BLA, enhanced consolidation of IA memory in rats when given at 1.5, 3, or 6 h posttraining, but not when the drug was infused immediately after training. In addition, intra-BLA administration of TSA immediately after retrieval delayed extinction learning. Moreover, we show that intra-BLA TSA in rats given IA training increased the levels of brain-derived neurotrophic factor in the dorsal hippocampus, but not in the BLA itself. These findings reveal novel aspects of the regulation of fear memory by epigenetic mechanisms in the amygdala

The versatility of membrane-water partitioning in pharmacokinetic modelling

info:eu-repo/semantics/publishedVersio

Intraoral lipoma with degenerative changes mimicking atypical lipomatous tumor: an immunohistochemical study

Lipomas are mesenchymal neoplasms relatively uncommon in the oral cavity. Lipomas can exhibit histopathological features mimicking atypical lipomatous tumors (ALT) or dysplastic lipoma (DL) in the presence of degenerative changes. Relevantly, immunohistochemistry assists in the correct diagnosis. Herein, we present the case of a 54-year-old male with a sessile nodule located on the dorsum of the tongue. The histopathological analysis showed a diffuse, non-circumscribed adipocytic proliferation constituted by cells of variable size containing cytoplasmic vacuoles and displaced nuclei, some resembling lipoblasts supported by fibrous connective tissue stroma. By immunohistochemistry, tumor cells were positive for vimentin, S100, FASN, CD10, and p16. Rb expression was intact. Moreover, CD34, p53, MDM2, and CDK4 were negative. After 2-year of follow-up, no alteration or recurrence was observed. In conclusion, MDM2, CDK4, p53, and Rb immunomarkers can be used reliably to differentiate benign lipoma with degenerative changes from ALT and DL