Caracterização química e resistência à flexão de uma resina acrílica após a incorporação de um polímero com atividade antimicrobiana

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Radiopacity and flow of different endodontic sealers

The present study evaluated the radiopacity and flow of different endodontic sealers: AH Plus, Endo CPM, MTA Fillapex, Sealapex, Epiphany, and Epiphany SE. For the radiopacity test, six specimens measuring 10mm in diameter and 1mm in thickness were fabricated from each material. They were radiographed on an occlusal film alongside an aluminum step wedge. Radiographs were digitized to determine the radiopacity equivalence in millimeters of aluminum. To evaluate the flow, a 120 g load was placed on top of a glass slab containing 0.05 } 0.005ml of sealer. The diameters of each material were measured (mm) with a caliper and samples were photographed. Digitized images were analyzed using the UTHSCSA Image Tool for Windows software, to determine the sealer area (mm2). Data were submitted to ANOVA and Tukey's test at 5% significance. AH Plus and Epiphany SE presented the greatest radiopacity (12.5 mm Al and 12.0 mm Al, respectively) (p>0.05), followed by Epiphany (9.6 mm Al) and Fillapex (8.9 mm Al). Endo CPM (5.46 mm Al) and Sealapex (5.51 mm Al) presented lower radiopacity. MTA Fillapex presented significantly higher values of flow than other sealers (33.11 mm and 844.9 mm2). AH Plus, Epiphany, and Epiphany SE had similar values. Endo CPM (21.05 mm and 342.8 mm2) and Sealapex (19.98 mm and 352.5 mm2) presented the lowest flow values (p>0.05). All sealers presented radiopacity and flow values according to ISO and ANSI/ADA recommendations.

Characterization of corn (Zea mays) leaf powder and Its adsorption properties regarding Cu(II) and Cd(II) from aqueous samples

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Orange pectin mediated growth and stability of aqueous gold and silver nanocolloids

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Dendrimer nanocarriers for transport modulation across models of the pulmonary epithelium

The purpose of this study was to determine the effect of PEGylation on the interaction of poly(amidoamine) (PAMAM) dendrimer nanocarriers (DNCs) with in vitro and in vivo models of the pulmonary epithelium. Generation-3 PAMAM dendrimers with varying surface densities of PEG 1000 Da were synthesized and characterized. The results revealed that the apical to basolateral transport of DNCs across polarized Calu-3 monolayers increases with an increase in PEG surface density. DNC having the greatest number of PEG groups (n = 25) on their surface traversed at a rate 10-fold greater than its non-PEGylated counterpart, in spite of their larger size. This behavior was attributed to a significant reduction in charge density upon PEGylation. We also observed that PEGylation can be used to modulate cellular internalization. The total uptake of PEG-free DNC into polarized Calu-3 monolayers was 12% (w/w) vs 2% (w/w) for that with 25 PEGs. Polarization is also shown to be of great relevance in studying this in vitro model of the lung epithelium. The rate of absorption of DNCs administered to mice lungs increased dramatically when conjugated with 25 PEG groups, thus supporting the in vitro results. The exposure obtained for the DNC with 25PEG was determined to be very high, with peak plasma concentrations reaching 5 mu gmL(-1) within 3 h. The combined in vitro and in vivo results shown here demonstrate that PEGylation can be potentially used to modulate the internalization and transport of DNCs across the pulmonary epithelium. Modified dendrimers thereby may serve as a valuable platform that can be tailored to target the lung tissue for treating local diseases, or the circulation, using the lung as pathway to the bloodstream, for systemic delivery.

Cassava root husks as a sorbent material for the uptake and pre-concentration of cadmium(II) from aqueous media

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Dança do ventre e feminilidade: análise dos relatos de praticantes

Pós-graduação em Psicologia do Desenvolvimento e Aprendizagem - FC

Aminas biogênicas e polifenóis no leite e queijo de ovelhas da raça Bergamácia suplementadas com óleo ou farelo de linhaça (Linum usitassimum L.)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Síntese, caracterização térmica e grau de conversão de polímeros dimetacrilatos com diferentes coiniciadores não tóxicos

The photopolimerization it is be widely used nowadays in different fields as materials, medicine and dentistry. To occur that synthesis is utilized dimethacrylates monomers and photoinitiators, the photoinitiator system more usual is camphorquinone/tertiary amine (ethyl-p-dimethylamino benzoate). However is knowledge that tertiary amines are toxics, so the aim of this work is replace toxic amine compounds to non-toxic compounds as glycerol and inositol. Therefore was used the FTIR technic to calculate the monomers conversion degree as well as Thermogravimetric Analysis-simultaneous differential thermal analysis (TG-DTA) and Differential Scanning Calorimetry (DSC) to evaluate thermal stability, combustion rate, degradation steps, oxidation and volatilization of all samples. The study shown no significant difference about thermal behavior of all polymers, the initiators system for efficient and more fastness was camphorquinone /tertiary amine system followed by ca mph o r quinone/glycerol system

Mutagenicity of Blue Rayon Extracts of Fish Bile as a Biomarker in a Field Study

Blue rayon (BR) in combination with the Salmonella/microsome assay was used to evaluate the mutagenicity of fish bile samples. Specimens of Mugil curema from two sites were collected over a 1-year period. Piacaguera channel contains high concentrations of total polycyclic aromatic hydrocarbons (PAHs) and other contaminants, while Bertioga channel was considered the reference sites in this study. Bile was extracted with BR and tested with TA98, TA100, and YG1041 strains with and without S9 in dose response experiments. PAH metabolite equivalents were analyzed using reverse-phase high performance liquid chromatography /fluorescence. Higher mutagenic responses were observed for the contaminated site; YG1041 with S9 was the most sensitive strain/condition. Mutagenicity ranged from 3,900 to 14,000 rev./mg at the contaminated site and from 1,200 to 2,500 rev./mg of BR at the reference site. The responses of YG1041 were much higher in comparison with the TA98 indicating the presence of polycyclic compounds from the aromatic amine class that cause frameshift mutation. TA100 showed a positive mutagenic response that was enhanced following S9 treatment at both sites suggesting the presence of polycyclic compounds that require metabolic activation. benzo(a)pyrene, naphthalene, and phenanthrene metabolite equivalents were also higher in the bile of fish collected at the contaminated site. It was not possible to correlate the PAH metabolite quantities with the mutagenic potency. Thus, a combination of the Salmonella/microsome assay with YG1041 with S9 from BR bile extract seems to be an acceptable biomarker for monitoring the exposure of fish to mutagenic polycyclic compounds. Environ. Mal. Mutagen. 51:173-179, 2010. (C) 2009 Wiley-Liss, Inc.

Polymerization kinetics and reactivity of alternative initiators systems for use in light-activated dental resins

Objectives. The purpose of this study was to evaluate the reactivity and polymerization kinetics behavior of a model dental adhesive resin with water-soluble initiator systems. Methods. A monomer blend based on Bis-GMA, TEGDMA and HEMA was used as a model dental adhesive resin, which was polymerized using a thioxanthone type (QTX) as a photoinitiator. Binary and ternary photoinitiator systems were formulated using 1 mol% of each initiator. The co-initiators used in this study were ethyl 4-dimethylaminobenzoate (EDAB), diphenyliodonium hexafluorophosphate (DPIHFP), 1,3-diethyl-2-thiobarbituric acid (BARB), p-toluenesulfinic acid and sodium salt hydrate (SULF). Absorption spectra of the initiators were measured using a UV-Vis spectrophotometer, and the photon absorption energy (PAE) was calculated. The binary system camphorquinone (CQ)/amine was used as a reference group (control). Twelve groups were tested in triplicate. Fourier-transform infrared spectroscopy (FTIR) was used to investigate the polymerization reaction during the photoactivation period to obtain the degree of conversion (DC) and maximum polymerization rate (R-p(max)) profile of the model resin. Results. In the analyzed absorption profiles, the absorption spectrum of QTX is almost entirely localized in the UV region, whereas that of CQ is in the visible range. With respect to binary systems, CQ + EDAB exhibited higher DC and R-p(max) values. In formulations that contained ternary initiator systems, the group CQ + QTX + EDAB was the only one of the investigated experimental groups that exhibited an R-p(max) value greater than that of CQ + EDAB. The groups QTX + EDAB + DPIHFP and QTX + DPIHFP + SULF exhibited values similar to those of CQ + EDAB with respect to the final DC; however, they also exhibited lower reactivity. Significance. Water-soluble initiator systems should be considered as alternatives to the widely used CQ/amine system in dentin adhesive formulations. (C) 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Cis-trans isomerization in the syntheses of ruthenium cyclam complexes with nitric oxide

The cis to trans isomerizations during the syntheses of trans-[Ru(NO)(OH)(cyclam)](PF6)(2), from cis-[RuCl2 (cyclam)]Cl, and [Ru(NO)Cl(cyclam)] (PF6)(2), from cis-[RuCl2(dmso)(4)], are reported. The novel trans-[Ru(NO) (OH)(cyclam)](PF6)(2) complex was characterized by X-ray crystallography and vibrational infrared and nuclear magnetic resonance spectroscopies. The Ru-N-O bond angle (176.75 degrees) and v( NO) (1835 cm(-1)) suggest a nitrosonium character for this hydroxo complex. The crystal and molecular structure of trans-[Ru(NO)Cl(cyclam)] (ClO4)(2)center dot 2 H2O is also reported. Results presented here support the cis-trans isomerization observed for the first time with ruthenium cyclam complexes. (C) 2011 Elsevier B.V. All rights reserved.

APTES-Modified RE2O3:Eu3+ Luminescent Beads: Structure and Properties

Europium-doped lanthanide oxide RE2O3:Eu3+ (RE = Y or Gd) luminescent beads, with a spherical shape and a diameter of 150 +/- 15 nm, have been modified by reaction with 3-aminopropyltriethoxysilane (APTES), in order to introduce reactive amine groups at their surfaces. The direct silanation has resulted in the formation of a nanometric layer at the surface of the beads, with an optimum grafting rate of 0.055 +/- 0.005 mol APTES/mol RE2O3. Fourier transform infrared (FTIR) and X-ray photoelectron (XPS) spectroscopies confirmed the condensation of an organosilane layer, made of cross-linked -O-Si-O-Si- and of groups -O-Si-R (with R = (CH2)(3)NH2 or O-Et). Titration of the accessible amine groups has been performed by simultaneously measuring the luminescence of grafted fluorescein isothiocyanate and that of core particles: there are about 2.3 X 10(4) (2.8 X 10(4)) -NH2 per Y2O3:Eu3+ (Gd2O3:Eu3+) bead. The isoelectronic point was shifted by one pH unit after APTES modification. The surface modification by APTES at least preserved (for Gd2O3:Eu3+) or improved (for Y2O3:Eu3+) the red emission of the beads.

Guanylate cyclase inhibition by methylene blue as an option in the treatment of vasoplegia after a severe burn. A medical hypothesis

Today it is known that severe burns can be accompanied by the phenomenon of vasoplegic syndrome (VS), which is manifested by persistent and diffuse vasodilation, hypotension and low vascular resistance, resulting in circulatory and respiratory failure. The decrease in systemic vascular resistance observed in VS is associated with excessive production of nitric oxide (NO). In the last 2 decades, studies have reported promising results from the administration of an NO competitor, methylene blue (MB), which is an inhibitor of the soluble guanylate cyclase (sGC), in the treatment of refractory cases of vasoplegia. This medical hypothesis rationale is focused on the tripod of burns/vasoplegia catecholamine resistant/methylene blue. This article has 3 main objectives: 1) to study the guanylate cyclase inhibition by MB in burns; 2) to suggest MB as a viable, safe and useful co-adjuvant therapeutic tool of fluid resuscitation, and; 3) to suggest MB as burns hypotensive vasoplegia amine-resistant treatment.

Synthesis and characterization of the atropisomeric relationships of a substituted N-phenyl-bipyrazole derivative with anti-inflammatory properties

This work describes the atropisomeric relationships of 3-methyl-5-(3-methyl-5-phenyl-1H-pyrazol-1-yl)-1-phenyl-1H-pyrazol-4-amine (2d), which belongs to series 4-aminobipyrazole derivatives designed as anti-inflammatory agents. The 1H nuclear magnetic resonance spectra obtained in the presence of a chiral lanthanide shift salt associated to chiral high-performance liquid chromatography analysis, X-ray diffraction, and molecular modeling tools confirmed that ortho bis-functionalized bipyrazole 2d exists as a mixture of aR,aS-atropisomers. These results provide useful information to understand the pharmacological profile of this derivative and of other 4-aminobipyrazole analogs. Chirality 24:463470, 2012. (c) 2012 Wiley Periodicals, Inc.