Efeito da associação de furosemida e fenilbutazona sobre variáveis hidroeletrolíticas de cavalos antes e após a corrida

Verificaram-se os efeitos da associação de furosemida e fenilbutazona sobre variáveis hidroeletrolíticas de cavalos antes e após a corrida. Dezenove equinos foram distribuídos em três grupos, de acordo com os protocolos de tratamento. O primeiro grupo, de cinco animais, não recebeu medicação (grupo-controle); o segundo grupo, de sete animais, foi tratado com furosemida, na dose de 1mg/kg, por via intramuscular, até quatro horas antes do páreo; o terceiro, de sete animais, recebeu furosemida, por via intramuscular, e fenilbutazona, por via intravenosa, nas doses de 1,0 e 4,4mg/kg, respectivamente, até quatro horas antes da corrida. Amostras de sangue foram colhidas antes, imediatamente após e duas horas após o páreo, para avaliação da osmolalidade plasmática e das concentrações plasmáticas de sódio, potássio e cloreto. A utilização de furosemida e da associação furosemida e fenilbutazona até 4h antes dos páreos nas dosagens descritas alterou (P0,05) as concentrações de sódio, potássio e cloreto. Os páreos alteraram de forma fisiológica a osmolalidade plasmática e a concentração sanguínea de K+ devido ao exercício de alta intensidade

Effect Of Fluoride-treated Enamel On Indirect Cytotoxicity Of A16% Carbamide Peroxide Bleaching Gel To Pulp Cells

The aim of this study was to evaluate the possibility of fluoride solutions applied to enamel to protect pulp cells against the trans-enamel and transdentinal cytotoxicity of a 16% carbamide peroxide (CP) bleaching gel. The CP gel was applied to enamel/ dentin discs adapted to artificial pulp chambers (8 h/day) during 1, 7 or 14 days, followed by fluoride (0.05% or 0.2%) application for 1 min. The extracts (culture medium in contact with dentin) were applied to MDPC-23 cells for 1 h, and cell metabolism (MTT assay), alkaline phosphatase (ALP) activity and cell membrane damage (flow cytometry) were analyzed. Knoop microhardness of enamel was also evaluated. Data were analyzed statistically by ANOVA and Kruskal-Wallis tests (a=0.05). For the MTT assay and ALP activity, significant reductions between the control and the bleached groups were observed (p0.05), regardless of fluoride application or treatment days. Flow cytometry analysis demonstrated 30% of cell membrane damage in all bleached groups. After 14 days of treatment, the fluoride-treated enamel presented significantly higher microhardness values than the bleached-only group (p<0.05). It was concluded that, regardless of the increase in enamel hardness due to the application of fluoride solutions, the treated enamel surface did not prevent the toxic effects caused by the 16% CP gel to odontoblast-like cells.242121127Markowitz, K., Pretty painful: Why does tooth bleaching hurt? (2010) Med Hypotheses, 74, pp. 835-840Soares, D.G., Ribeiro, A.P., da Silveira Vargas, F., Hebling, J., de Souza Costa, C.A., Efficacy and cytotoxicity of a bleaching gel after short application times on dental enamel (2012) Clin Oral Investig, , [Epub ahead of print. DOI: 10.1007/s00784-012-0883-1]De Souza Costa, C.A., Riehl, H., Kina, J.F., Sacono, N.T., Hebling, J., Human pulp responses to in-office tooth bleaching (2010) Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 109, pp. e59-e64Coldebella, C.R., Ribeiro, A.P., Sacono, N.T., Trindade, F.Z., Hebling, J., Costa, C.A., Indirect cytotoxicity of a 35% hydrogen peroxide bleaching gel on cultured odontoblast-like cells (2009) Braz Dent J, 20, pp. 267-274Trindade, F.Z., Ribeiro, A.P., Sacono, N.T., Oliveira, C.F., Lessa, F.C., Hebling, J., Trans-enamel and trans-dentinal cytotoxic effects of a 35% HP bleaching gel on cultured odontoblast cell lines after consecutive applications (2009) Int Endod J, 42, pp. 516-524Kina, J.F., Huck, C., Riehl, H., Martinez, T.C., Sacono, N.T., Ribeiro, A.P., Response of human pulps after professionally applied vital tooth bleaching (2010) Int Endod J, 43, pp. 572-580Lima, A.F., Lessa, F.C., Mancini, M.N., Hebling, J., Costa, C.A., Marchi, G.M., Transdentinal protective role of sodium ascorbate against the cytopathic effects of HP released from bleaching agents (2010) Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 109, pp. e70-e76Soares, D.G., Ribeiro, A.P., Sacono, N.T., Coldebella, C.R., Hebling, J., Costa, C.A., Transenamel and transdentinal cytotoxicity of carbamide peroxide bleaching gels on odontoblast-like MDPC-23 cells (2011) Int Endod J, 44, pp. 116-125Lima, A.F., Ribeiro, A.P., Soares, D.G., Sacono, N.T., Hebling, J., de Souza Costa, C.A., Toxic effects of daily applications of 10% carbamide peroxide on odontoblast-like MDPC-23 cells (2013) Acta Odontol Scand, , Epub ahead of print. DOI:10.3109/00016357.2012.762992]Eimar, H., Siciliano, R., Abdallah, M.N., Nader, S.A., Amin, W.M., Martinez, P.P., Hydrogen peroxide whitens teeth by oxidizing the organic structure (2012) J Dent, 40, pp. e25-e33Gökay, O., Müjdeci, A., Algin, E., In vitro peroxide penetration into the pulp chamber from newer bleaching products (2005) Int Endod J, 38, pp. 516-520Meireles, S.S., Santos, I.S., Bona, A.D., Demarco, F.F., A double-blind randomized clinical trial of two carbamide peroxide tooth bleaching agents: 2-year follow-up (2010) J Dent, 38, pp. 956-963Borges, A.B., Samezima, L.Y., Fonseca, L.P., Yui, K.C., Borges, A.L., Torres, C.R., Influence of potentially remineralizing agents on bleached enamel microhardness (2009) Oper Dent, 34, pp. 593-597Borges, A.B., Yui, K.C., D'avila, T.C., Takahashi, C.L., Torres, C.R., Borges, A.L., Influence of remineralizing gels on bleached enamel microhardness in different time intervals (2010) Oper Dent, 35, pp. 180-186Cavalli, V., Rodrigues, L.K., Paes-Leme, A.F., Brancalion, M.L., Arruda, M.A., Berger, S.B., Effects of bleaching agents containing fluoride and calcium on human enamel (2010) Quintessence Int, 41, pp. e157-e165Cavalli, V., Rodrigues, L.K., Paes-Leme, A.F., Soares, L.E., Martin, A.A., Berger, S.B., Effects of the addition of fluoride and calcium to low-concentrated carbamide peroxide agents on the enamel surface and subsurface (2011) Photomed Laser Surg, 29, pp. 319-325Armênio, R.V., Fitarelli, F., Armênio, M.F., Demarco, F.F., Reis, A., Loguercio, A.D., The effect of fluoride gel use on bleaching sensitivity: A double-blind randomized controlled clinical trial (2008) J Am Dent Assoc, 139, pp. 592-597Kose, C., Reis, A., Baratieri, L.N., Loguercio, A.D., Clinical effects of at-home bleaching along with desensitizing agent application (2011) Am J Dent, 24, pp. 379-382Reis, A., Dalanhol, A.P., Cunha, T.S., Kossatz, S., Loguercio, A.D., Assessment of tooth sensitivity using a desensitizer before light-activated bleaching (2011) Oper Dent, 36, pp. 12-17Read, S.M., Northcote, D.H., Minimization of variation in the response to different proteins of the Coomassie blue G dye-binding assay for protein (1981) Anal Biochem, 116, pp. 53-64Min, K.S., Lee, H.J., Kim, S.H., Lee, S.K., Kim, H.R., Pae, H.O., Hydrogen peroxide induces Heme Oxygenase-1 and dentin sialophosphoprotein m RNA in human pulp cells (2008) J Endod, 34, pp. 983-989Goodis, H.E., Bowles, W.R., Hargreaves, K.M., Prostaglandin E2 enhances bradykinin-evoked iCGRP release in bovine dental pulp (2000) J Dent Res, 79, pp. 1604-1607Markowitz, K., Bilotto, G., Kim, S., Decreasing intradental nerve activity in the cat with potassium and divalent cations (1991) Arch Oral Biol, 36, pp. 1-7Boushell, L.W., Ritter, A.V., Garland, G.E., Tiwana, K.K., Smith, L.R., Broome, A., Nightguard vital bleaching: Side effects and patient satisfaction 10 to 17 years post-treatment (2012) J Esthet Restor Dent, 24, pp. 211-219Sauro, S., Pashley, D.H., Montanari, M., Chersoni, S., Carvalho, R.M., Toledano, M., Effect of simulated pulpal pressure on dentin permeability and adhesion of self-etch adhesives (2007) Dent Mater, 23, pp. 705-71

Sorghum Growth Promotion by Paraburkholderia tropica and Herbaspirillum frisingense: Putative Mechanisms Revealed by Genomics and Metagenomics

Bacteria from the genera Paraburkholderia and Herbaspirillum can promote the growth of Sorghum bicolor, but the underlying mechanisms are not yet known. In a pot experiment, sorghum plants grown on sterilized substrate were inoculated with Paraburkholderia tropica strain IAC/BECa 135 and Herbaspirillum frisingense strain IAC/BECa 152 under phosphate-deficient conditions. These strains significantly increased Sorghum bicolor cultivar SRN-39 root and shoot biomass. Shotgun metagenomic analysis of the rhizosphere revealed successful colonization by both strains; however, the incidence of colonization was higher in plants inoculated with P. tropica strain IAC/BECa 135 than in those inoculated with H. frisingense strain IAC/BECa 152. Conversely, plants inoculated with H. frisingense strain IAC/BECa 152 showed the highest increase in biomass. Genomic analysis of the two inoculants implied a high degree of rhizosphere fitness of P. tropica strain IAC/BECa 135 through environmental signal processing, biofilm formation, and nutrient acquisition. Both genomes contained genes related to plant growth-promoting bacterial (PGPB) traits, including genes related to indole-3-acetate (IAA) synthesis, nitrogen fixation, nodulation, siderophore production, and phosphate solubilization, although the P. tropica strain IAC/BECa 135 genome contained a slightly more extensive repertoire. This study provides evidence that complementary mechanisms of growth promotion in Sorghum might occur, i.e., that P. tropica strain IAC/BECa 135 acts in the rhizosphere and increases the availability of nutrients, while H. frisingense strain IAC/BECa 152 influences plant hormone signaling. While the functional and taxonomic profiles of the rhizobiomes were similar in all treatments, significant differences in plant biomass were observed, indicating that the rhizobiome and the endophytic microbial community may play equally important roles in the complicated plant-microbial interplay underlying increased host plant growt

Effect Of Low-level Laser Therapy On Odontoblast-like Cells Exposed To Bleaching Agent

The aim of the present study was to evaluate the effect of low-level laser therapy (LLLT) on odontoblast-like MDPC-23 cells exposed to carbamide peroxide (CP 0.01 %-2.21 μg/mL of H2O2). The cells were seeded in sterile 24-well plates for 72 h. Eight groups were established according to the exposure or not to the bleaching agents and the laser energy doses tested (0, 4, 10, and 15 J/cm2). After exposing the cells to 0.01 % CP for 1 h, this bleaching solution was replaced by fresh culture medium. The cells were then irradiated (three sections) with a near-infrared diode laser (InGaAsP-780 ± 3 nm, 40 mW), with intervals of 24 h. The 0.01 % CP solution caused statistically significant reductions in cell metabolism and alkaline phosphate (ALP) activity when compared with those of the groups not exposed to the bleaching agent. The LLLT did not modulate cell metabolism; however, the dose of 4 J/cm2 increased the ALP activity. It was concluded that 0.01 % CP reduces the MDPC-23 cell metabolism and ALP activity. The LLLT in the parameters tested did not influence the cell metabolism of the cultured cells; nevertheless, the laser dose of 4 J/cm2 increases the ALP activity in groups both with and without exposure to the bleaching agent. © 2013 Springer-Verlag London.1

Effects Of Laser Irradiation On Pulp Cells Exposed To Bleaching Agents

The aim of this study was to evaluate the effect of low-level laser therapy (LLLT) on odontoblast-like cells exposed to a bleaching agent. Mouse dental papilla cell-23 cells were seeded in wells of 24-well plates. Eight groups were established according to the exposure to the bleaching agent and LLLT (0, 4, 10 and 15 J cm-2). Enamel-dentin disks were adapted to artificial pulp chambers, which were individually placed in wells containing Dulbecco's modified Eagle's medium (DMEM). A bleaching agent (35% hydrogen peroxide [BA35%HP]) was applied on enamel (15 min) to obtain the extracts (DMEM + BA35%HP components diffused through enamel/dentin disks). The extracts were applied (1 h) to the cells, and then subjected to LLLT. Cell viability (Methyl tetrazolium assay), alkaline phosphatase (ALP) activity, as well as gene expression of ALP, fibronectin (FN) and type I collagen, were evaluated. The bleaching procedures reduced the cell viability, ALP activity and gene expression of dentin proteins. Laser irradiation did not modulate the cell response; except for FN, as LLLT decreased the gene expression of this protein by the cells exposed to the BA35%HP. It can be concluded that BA35%HP decreased the activities of odontoblasts that were not recovered by the irradiation of the damaged cells with low-level laser parameters tested. The aim of the present study was to evaluate the effect of low-level laser therapy (LLLT) on odontoblast-like cells exposed to a bleaching agent. Eight groups were established according to the exposure to the bleaching agent (35% hydrogen peroxide) and LLLT (0, 4, 10, and 15 J cm-2). The bleaching procedures reduced the cell viability, ALP activity, and gene expression of dentin proteins. Laser irradiation did not modulate the cell response; except for FN, since LLLT decreased the gene expression of this protein by the cells exposed to the 35% hydrogen peroxide. © 2013 The American Society of Photobiology.901201206Costa, C.A., Riehl, H., Kina, J.F., Sacono, N.T., Hebling, J., Human pulp responses to in-office tooth bleaching (2010) Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod., 109, pp. e59-e64Dias Ribeiro, A.P., Sacono, N.T., Lessa, F.C., Nogueira, I., Coldebella, C.R., Hebling, J., De Souza Costa, C.A., Cytotoxic effect of a 35% hydrogen peroxide bleaching gel on odontoblast-like MDPC-23 cells (2009) Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod., 108, pp. 458-464De Lima, A.F., Lessa, F.C., Gasparoto Mancini, M.N., Hebling, J., De Souza Costa, C.A., Marchi, G.M., Cytotoxic effects of different concentrations of a carbamide peroxide bleaching gel on odontoblast-like cells MDPC-23 (2009) J. Biomed. Mater. Res. B Appl. Biomater., 90, pp. 907-912Lima, A.F., Lessa, F.C., Hebling, J., De Souza Costa, C.A., Marchi, G.M., Protective effect of sodium ascorbate on MDPC-23 odontoblast-like cells exposed to a bleaching agent (2010) Eur. J. Dent., 4, pp. 238-244Dantas, C.M., Vivan, C.L., Ferreira, L.S., Freitas, P.M., Marques, M.M., In vitro effect of low intensity laser on the cytotoxicity produced by substances released by bleaching gel (2010) Braz. Oral Res., 24, pp. 460-466Robertson, W.D., Melfi, R.C., Pulpal response to vital bleaching procedures (1980) J. Endod., 6, pp. 645-649Kina, J.F., Huck, C., Riehl, H., Martinez, T.C., Sacono, N.T., Ribeiro, A.P., Costa, C.A., Response of human pulps after professionally applied vital tooth bleaching (2010) Int. Endod. J., 43, pp. 572-580Kawamoto, K., Tsujimoto, Y., Effects of the hydroxyl radical and hydrogen peroxide on tooth bleaching (2004) J. Endod., 30, pp. 45-50Gokay, O., Mujdeci, A., Algin, E., In vitro peroxide penetration into the pulp chamber from newer bleaching products (2005) Int. Endod. J., 38, pp. 516-520Hanks, C.T., Fat, J.C., Wataha, J.C., Corcoran, J.F., Cytotoxicity and dentin permeability of carbamide peroxide and hydrogen peroxide vital bleaching materials, in vitro (1993) J. Dent. Res., 72, pp. 931-938Asfora, K.K., Santos Mdo, C., Montes, M.A., De Castro, C.M., Evaluation of biocompatibility of sodium perborate and 30% hydrogen peroxide using the analysis of the adherence capacity and morphology of macrophages (2005) J. Dent., 33, pp. 155-162Karu, T., Pyatibrat, L., Kalendo, G., Irradiation with He-Ne laser increases ATP level in cells cultivated in vitro (1995) J. Photochem. Photobiol. B, 27, pp. 219-223Khadra, M., Lyngstadaas, S.P., Haanaes, H.R., Mustafa, K., Effect of laser therapy on attachment, proliferation and differentiation of human osteoblast-like cells cultured on titanium implant material (2005) Biomaterials, 26, pp. 3503-3509Oliveira, C.F., Basso, F.G., Lins, E.C., Kurachi, C., Hebling, J., Bagnato, V.S., Costa, C.A.D., Increased viability of odontoblast-like cells subjected to low-level laser irradiation (2010) Laser Phys., 20, pp. 1659-1666Kossatz, S., Dalanhol, A.P., Cunha, T., Loguercio, A., Reis, A., Effect of light activation on tooth sensitivity after in-office bleaching (2011) Oper. Dent., 36, pp. 251-257Reis, A., Dalanhol, A.P., Cunha, T.S., Kossatz, S., Loguercio, A.D., Assessment of tooth sensitivity using a desensitizer before light-activated bleaching (2011) Oper. Dent., 36, pp. 12-17Lima, A.F., Ribeiro, A.P., Basso, F.G., Bagnato, V.S., Hebling, J., Marchi, G.M., De Souza Costa, C.A., Effect of low-level laser therapy on odontoblast-like cells exposed to bleaching agent (2013) Lasers Med. Sci., , (In press, DOI: 10.1007/s10103-013-1309-2)Hanks, C.T., Sun, Z.L., Fang, D.N., Edwards, C.A., Wataha, J.C., Ritchie, H.H., Butler, W.T., Cloned 3T6 cell line from CD-1 mouse fetal molar dental papillae (1998) Connect. Tissue Res., 37, pp. 233-249Sun, Z.L., Fang, D.N., Wu, X.Y., Ritchie, H.H., Begue-Kirn, C., Wataha, J.C., Hanks, C.T., Butler, W.T., Expression of dentin sialoprotein (DSP) and other molecular determinants by a new cell line from dental papillae, MDPC-23 (1998) Connect. Tissue Res., 37, pp. 251-261Chandler, N.P., The radiographic assessment of pulp size: Validity and clinical implications (1989) N. Z. Dent. J., 85, pp. 23-26Jacques, P., Hebling, J., Effect of dentin conditioners on the microtensile bond strength of a conventional and a self-etching primer adhesive system (2005) Dent. Mater., 21, pp. 103-109Lima, A.F., Lessa, F.C., Mancini, M.N., Hebling, J., Costa, C.A., Marchi, G.M., Transdentinal protective role of sodium ascorbate against the cytopathic effects of H2O2 released from bleaching agents (2010) Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod., 109, pp. e70-e76Basso, F.G., Oliveira, C.F., Kurachi, C., Hebling, J., Costa, C.A., Biostimulatory effect of low-level laser therapy on keratinocytes in vitro (2013) Lasers Med. Sci., 28 (2), pp. 367-374Mosmann, T., Rapid colorimetric assay for cellular growth and survival: Application to proliferation and cytotoxicity assays (1983) J. Immunol. Methods, 65, pp. 55-63De Mendonca, A.A., Souza, P.P., Hebling, J., Costa, C.A., Cytotoxic effects of hard-setting cements applied on the odontoblast cell line MDPC-23 (2007) Oral Surg. 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Mutant P53 Aggregates Into Prion-like Amyloid Oligomers And Fibrils: Implications For Cancer

Over 50% of all human cancers lose p53 function. To evaluate the role of aggregation in cancer, we asked whether wild-type (WT) p53 and the hot-spot mutant R248Q could aggregate as amyloids under physiological conditions and whether the mutant could seed aggregation of the wild-type form. The central domains (p53C) of both constructs aggregated into a mixture of oligomers and fibrils. R248Q had a greater tendency to aggregate than WT p53. Full-length p53 aggregated into amyloid-like species that bound thioflavin T. The amyloid nature of the aggregates was demonstrated using x-ray diffraction, electron microscopy, FTIR, dynamic light scattering, cell viabilility assay, and anti-amyloid immunoassay. The x-ray diffraction pattern of the fibrillar aggregates was consistent with the typical conformation of cross β-sheet amyloid fibers with reflexions of 4.7 Å and 10 Å. A seed of R248Q p53C amyloid oligomers and fibrils accelerated the aggregation of WT p53C, a behavior typical of a prion. The R248Q mutant co-localized with amyloid-like species in a breast cancer sample, which further supported its prion-like effect. A tumor cell line containing mutant p53 also revealed massive aggregation of p53 in the nucleus. We conclude that aggregation of p53 into a mixture of oligomers and fibrils sequestrates the native protein into an inactive conformation that is typical of a prionoid. This prion-like behavior of oncogenic p53 mutants provides an explanation for the negative dominance effect and may serve as a potential target for cancer therapy. © 2012 by The American Society for Biochemistry and Molecular Biology, Inc.287332815228162Vousden, K.H., Lane, D.P., p53 in health and disease (2007) Nat. Rev. Mol. Cell Biol., 8, pp. 275-283Joerger, A.C., Fersht, A.R., Structural biology of the tumor suppressor p53 (2008) Annu. Rev. 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