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OBJECTIVE: This study aimed to compare the tooth color matching of two dental colorimetric methods: the spectrophotometric analysis (SPM) and the standardized digital photocolorimetric analysis (DPC). METHODS: The color of 60 maxillary central incisors of 30 volunteers (22.5 ± 7.6 years) was analyzed. In the DPC method, tooth photographs were standardized with the eLABor_aid protocol, processed with Adobe Photoshop Lightroom software, and the values of L*, a*, and b* were obtained with a Digital Color Meter software. For the SPM, L*, a*, and b* were measured directly with a handheld spectrophotometer. Data were submitted to paired t-test and Pearson correlation test (α=0.05). Mean color difference between the two methods was calculated with CIELAB formula. RESULTS: All color coordinates revealed different values when comparing DPC to SPM in the same tooth (p<0.0001). Mean color difference (ΔEab) between SPM and DPC was 11.5 ±3.1. A positive correlation was observed for L* (R2=0.73,p<0.0001), a* (R2=0.31, p=0.017), and b* (R2=0.83, p<0.0001). CONCLUSIONS: Even though the color coordinate values were different in both methods, they were correlated, revealing that the DPC is a viable alternative to determine the tooth color matching.

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The intriguing questions concerning gall development refer to the processes of the remodelling of the host plant organ. Such processes involve the restructuring of cell walls and can be influenced by phenolics, indole-3-acetic acid (IAA) and reactive oxygen species (ROS). Alterations in cell walls demand the interference in the coupling of cellulose fibrils and hemicelluloses (xyloglucans) at specific stages of gall development. In addition to cell wall remodelling, hemicelluloses, such as the, xyloglucans and heteromannans can act as reserve carbohydrates, while xylans provide rigidity to the secondary cell walls. Developmental traits of the lenticular, fusiform and globoid galls on Inga ingoides (Fabaceae) were analysed using anatomical, cytometric, histochemical and immunocytochemical tools. Phenolics, IAA and ROS accumulated in similar gall tissue compartments, and may have influenced the restructuring of hemicelluloses and pectins. Contrary to expectations, cell wall flexibility regarding the dynamics of xyloglucans and cellulose fibrils does not relate to a temporal scale. The detection of xyloglucans in nutritive cell walls relate to carbohydrate nutritional resources to the galling insect, while xylans were associated to the lignified cell walls. Heteromanans were not detected, either in non-galled or galled tissues. The patterns of cell expansion during gall development relied on the relationship among phenolics, ROS and IAA with the hemicelluloses (xyloglucans and xylans) and cellulose fibrils. Although cell wall dynamics is specific to each gall morphotype in I. ingoides, the xyloglucans function as carbohydrate reserve to the gall inducers, which constitutes a functional trait common to the three morphotypes.

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The galls induced by Ditylenchus gallaeformans (Nematoda) on leaves of Miconia albicans have unique features when compared to other galls. The nematode colonies are surrounded by nutritive tissues with promeristematic cells, capable of originating new emergences facing the larval chamber, and providing indeterminate growth to these galls. Considering enzyme activity as essential for the translocation of energetic molecules from the common storage tissue (CST) to the typical nutritive tissue (TNT), and the major occurrence of carbohydrates in nematode galls, it was expected that hormones would mediate sink strength relationships by activating enzymes in indeterminate growth regions of the galls. Histochemical, immunocytochemical and quantitative analyses were made in order to demonstrate sites of enzyme activity and hormones, and comparative levels of total soluble sugars, water soluble polysaccharides and starch. The source-sink status, via carbohydrate metabolism, is controlled by the major accumulation of cytokinins in totipotent nutritive cells and new emergences. Thus, reducing sugars, such as glucose and fructose, accumulate in the TNT, where they supply the energy for successive cycles of cell division and for nematode feeding. The histochemical detection of phosphorylase and invertase activities indicates the occurrence of starch catabolism and sucrose transformation into reducing sugars, respectively, in the establishment of a gradient from the CST towards the TNT. Reducing sugars in the TNT are important for the production of new cell walls during the indeterminate growth of the galls, which have increased levels of water-soluble polysaccharides that corroborate such a hypothesis. Functional relationship between plant hormone accumulation, carbohydrate metabolism and cell differentiation in D. gallaeformans-induced galls is attested, providing new insights on cell development and plant metabolism.

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Os compostos fenólicos encontrados no extrato das folhas de maracujazeiro doce (Passiflora alata Curtis) são os principais responsáveis pelos efeitos terapêuticos, incluindo a atividade ansiolítica. O presente trabalho avaliou o efeito de diferentes espécies de fungo micorrízicos arbusculares (FMAs) e doses de fósforo sobre a bioprodução de fenóis totais, bem como, o crescimento vegetal e os conteúdos de nitrogênio, fósforo e potássio na massa da matéria seca da parte aérea do maracujazeiro doce. O experimento, fatorial 4x2, foi conduzido em um telado com quatro tratamentos microbiológicos: Glomus etunicatum, Glomus intraradices, inóculo misto (Glomus clarum e Gigaspora margarita) e o controle sem fungo, e duas doses de fósforo: 0 e 50 mg kg-1 de solo. O delineamento experimental foi de blocos casualizados com quatro repetições. As plantas foram colhidas 90 dias após a semeadura. Na ausência da adubação fosfatada, o conteúdo de fenóis totais, a massa da matéria seca da parte aérea e o número de folhas foram maiores nos tratamentos inoculados com FMAs, quando comparados ao tratamento sem fungo. Plantas com inóculo misto apresentaram maior altura com ou sem adubação fosfatada. Os tratamentos inoculados com FMAs, tanto na dose 0 quanto na dose 50 mg kg-1 de P incrementaram os conteúdos de N, P e K na parte aérea do maracujazeiro doce, evidenciando a capacidade dos FMAs em promover o melhor estado nutricional das plantas.

The phenolic compounds found in extracts from leaves of sweet passion fruit (Passiflora alata) are mainly responsible for its therapeutic effects, such as the anxiolytic activity. This study evaluated the effects of different species of mycorrhizal fungi (AMF) and phosphorus levels on the bioproduction of total phenols, as well as plant growth and the contents of nitrogen, phosphorus and potassium in the dry mass of shoots of sweet passion fruit. The experiment was conducted in a greenhouse. The factors were arranged in a :[(microbiological treatments: Glomus etunicatum, Glomus intraradices, mixed inoculum (Glomus clarum and Gigaspora margarita) and without fungus] x 2 (doses of phosphorus: 0 and 50 mg kg-1 soil) factorial arrangement, in a randomized block experimental design with four replications. The plants were harvested 90 days after seeding. In the absence of phosphate fertilization, the total phenol content, dry mass of shoot and leaf number were greater in treatments inoculated with AMF compared to the treatments without fungus. Mixed inoculum plants had higher plant height with or without phosphate fertilization. Treatments inoculated with AMF in both the 0 and 50 mg kg-1 doses of P increased the content of N, P and K in the shoots of sweet passion fruit, demonstrating the ability of AMF to promote better nutritional statusfin plants.

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The aim of this study was to evaluate the influence of tooth bleaching on the push-out bond strength of a composite resin based on dimethacrylates and silorane to cavities that involve both enamel and dentin. A total of 80 bovine incisors were sectioned on the buccal surface to obtain specimens (10 × 10 mm) presenting enamel and dentin (1-mm thick each substrate). The specimens were randomly distributed into eight groups (n=10), according to the bleaching protocol (1--none; 2--10% carbamide peroxide [CP] for 21 days, six hours each day; 3--three applications of 35% hydrogen peroxide [HP] in 15-minute sessions, one session every seven days for three weeks; 4--10% CP for 18 days, six hours each day + three applications of 35% HP in 15-minute sessions, one session every seven days for three weeks) and the restorative system applied (Adper Single Bond 2 + Filtek Supreme; Filtek Silorane adhesive and composite resin). After treatment, cavities were made (1.2-mm diameter on dentin; 1.5-mm diameter on enamel) with a diamond bur. At 24 hours after restoration, a push-out bond strength test was performed at a crosshead speed of 0.5 mm/min. The bleaching treatments did not significantly affect the bond strengths of either restorative system to enamel-dentin. Regardless of the bleaching treatment, the dimethacrylate-based resin system exhibited significantly higher bond strengths to enamel-dentin than did the silorane-based system.

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Chronic myeloid leukemia (CML) is rare in the pediatric population, accounting for 2-3 percent of childhood leukemia cases, with an annual incidence of one case per million children. The low toxicity profile of imatinib mesylate has led to its approval as a front-line therapy in children for whom interferon treatment has failed or who have relapsed after allogeneic transplantation. We describe the positive responses of 2 children (case 1 - from a 7-year-old male since May 2005; case 2 - from a 5-year-old female since June 2006) with Philadelphia-positive chromosome CML treated with imatinib (300 mg/day, orally) for up to 28 months, as evaluated by morphological, cytogenetic, and molecular approaches. Our patients are alive, are in the chronic phase, and are in continuous morphological complete remission.

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Chronic myeloid leukemia (CML) is rare in the pediatric population, accounting for 2-3% of childhood leukemia cases, with an annual incidence of one case per million children. The low toxicity profile of imatinib mesylate has led to its approval as a front-line therapy in children for whom interferon treatment has failed or who have relapsed after allogeneic transplantation. We describe the positive responses of 2 children (case 1 - from a 7-year-old male since May 2005; case 2 - from a 5-year-old female since June 2006) with Philadelphia-positive chromosome CML treated with imatinib (300 mg/day, orally) for up to 28 months, as evaluated by morphological, cytogenetic, and molecular approaches. Our patients are alive, are in the chronic phase, and are in continuous morphological complete remission.

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The alpha2ß1 integrin is a major collagen receptor that plays an essential role in the adhesion of normal and tumor cells to the extracellular matrix. Alternagin-C (ALT-C), a disintegrin-like protein purified from the venom of the Brazilian snake Bothrops alternatus, competitively interacts with the alpha2ß1 integrin, thereby inhibiting collagen binding. When immobilized in plate wells, ALT-C supports the adhesion of fibroblasts as well as of human vein endothelial cells (HUVEC) and does not detach cells previously bound to collagen I. ALT-C is a strong inducer of HUVEC proliferation in vitro. Gene expression analysis was done using an Affimetrix HU-95A probe array with probe sets of 10,000 human genes. In human fibroblasts growing on collagen-coated plates, ALT-C up-regulates the expression of several growth factors including vascular endothelial growth factor, as well as some cell cycle control genes. Up-regulation of the vascular endothelial growth factor gene and other growth factors could explain the positive effect on HUVEC proliferation. ALT-C also strongly activates protein kinase B phosphorylation, a signaling event involved in endothelial cell survival and angiogenesis. In human neutrophils, ALT-C has a potent chemotactic effect modulated by the intracellular signaling cascade characteristic of integrin-activated pathways. Thus, ALT-C acts as a survival factor, promoting adhesion, migration and endothelial cell proliferation after binding to alpha2ß1 integrin on the cell surface. The biological activities of ALT-C may be helpful as a therapeutic strategy in tissue regeneration as well as in the design of new therapeutic agents targeting alpha2ß1 integrin.

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Extracellular matrix proteins and cell adhesion receptors (integrins) play essential roles in the regulation of cell adhesion and migration. Interactions of integrins with the extracellular matrix proteins lead to phosphorylation of several intracellular proteins such as focal adhesion kinase, activating different signaling pathways responsible for the regulation of a variety of cell functions, including cytoskeleton mobilization. Once leukocytes are guided to sites of infection, inflammation, or antigen presentation, integrins can participate in the initiation, maintenance, or termination of the immune and inflammatory responses. The modulation of neutrophil activation through integrin-mediated pathways is important in the homeostatic control of the resolution of inflammatory states. In addition, during recirculation, T lymphocyte movement through distinct microenvironments is mediated by integrins, which are critical for cell cycle, differentiation and gene expression. Disintegrins are a family of low-molecular weight, cysteine-rich peptides first identified in snake venom, usually containing an RGD (Arg-Gly-Asp) motif, which confers the ability to selectively bind to integrins, inhibiting integrin-related functions in different cell systems. In this review we show that, depending on the cell type and the microenvironment, disintegrins are able to antagonize the effects of integrins or to act agonistically by activating integrin-mediated signaling. Disintegrins have proven useful as tools to improve the understanding of the molecular events regulated by integrin signaling in leukocytes and prototypes in order to design therapies able to interfere with integrin-mediated effects.

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Extracellular matrix proteins and cell adhesion receptors (integrins) play essential roles in the regulation of cell adhesion and migration. Interactions of integrins with the extracellular matrix proteins lead to phosphorylation of several intracellular proteins such as focal adhesion kinase, activating different signaling pathways responsible for the regulation of a variety of cell functions, including cytoskeleton mobilization. Once leukocytes are guided to sites of infection, inflammation, or antigen presentation, integrins can participate in the initiation, maintenance, or termination of the immune and inflammatory responses. The modulation of neutrophil activation through integrin-mediated pathways is important in the homeostatic control of the resolution of inflammatory states. In addition, during recirculation, T lymphocyte movement through distinct microenvironments is mediated by integrins, which are critical for cell cycle, differentiation and gene expression. Disintegrins are a family of low-molecular weight, cysteine-rich peptides first identified in snake venom, usually containing an RGD (Arg-Gly-Asp) motif, which confers the ability to selectively bind to integrins, inhibiting integrin-related functions in different cell systems. In this review we show that, depending on the cell type and the microenvironment, disintegrins are able to antagonize the effects of integrins or to act agonistically by activating integrin-mediated signaling. Disintegrins have proven useful as tools to improve the understanding of the molecular events regulated by integrin signaling in leukocytes and prototypes in order to design therapies able to interfere with integrin-mediated effects.

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