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1.
Braz. dent. j ; 28(2): 196-200, mar.-Apr. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-839127

RESUMEN

Abstract The aim of this study was to formulate and evaluate an experimental adhesive resin with the addition of 1,3,5-triacryloylhexahydro-1,3,5-triazine at different concentrations. Experimental adhesive resins were obtained by mixing 50% wt bisphenol A glycol dimethacrylate (BisGMA), 25% wt triethylene glycol dimethacrylate (TEGDMA), 25% wt 2-hydroxyethyl methacrylate (HEMA) and photoinitiator system. The triazine compound was added in 1, 2.5 and 5% wt to a base adhesive resin and one group remained with no triazine as control group. The experimental adhesive resins were analyzed for antibacterial activity (n=3), degree of conversion (n=3) and softening in solvent (n=3). Data distribution was evaluated by Kolmogorov-Smirnov test, paired t test, one-way ANOVA and Tukey’s with a 0.05 level of significance. All groups with added triazine compound showed antibacterial activity against Streptococcus mutans (p<0.05). All groups achieved more than 70% degree of conversion, but there was no difference in this chemical property (p>0.05). The initial Knoop hardness was higher in 2.5 and 5% wt groups (p<0.05) and both groups present lower percentage variation of Knoop hardness after solvent degradation. The present study formulated an antibacterial adhesive resin with a non-releasing agent able to copolymerize with the comonomeric blend, improving the restorative material’s properties.


Resumo O objetivo desse estudo foi desenvolver e avaliar a adição de 1,3,5-triacryloylhexahydro-1,3,5-triazine a uma resina adesiva experimental em diferentes concentrações. Resinas adesivas experimentais foram obtidas a partir da mistura de 50% em peso de bisphenol A glycol dimethacrylate (BisGMA), 25% em peso de triethylene glycol dimethacrylate (TEGDMA), 25% em peso de hidroxietil metacrilato (HEMA) e sistema fotoiniciador. O composto de triazina foi adicionado em proporções de 1; 2,5 e 5% em peso a resina adesiva base e um grupo permaneceu sem a adição do composto de triazina como grupo controle. As resinas adesivas experimentais foram analisadas por atividade antibacteriana (n=3), grau de conversão (n=3) e degradação em solvente (n=3). A distribuição dos dados foi avaliada por teste de Kolmogorov-Smirnov, teste t pareado, ANOVA de uma via e Tukey, considerando nível de significância de 5%. Todos os grupos com adição de composto de triazina demonstraram atividade antibacteriana contra Streptococcus mutans (p<0,05). Todos os grupos atingiram mais de 70% de grau de conversão, mas não houve diferença estatística para essa propriedade química (p>0,05). A dureza Knoop inicial foi maior para os grupos com 2,5 e 5% de triazina (p<0,05) e ambos os grupos apresentaram menor variação percentual de dureza Knoop após degradação em solvente. No presente estudo, foi produzida uma resina adesiva antibacteriana com agente sem liberação para o meio, capaz de copolimerizar com a blenda comonomérica, melhorando as propriedades do material restaurador.


Asunto(s)
Antibacterianos/farmacología , Materiales Dentales , Triazinas/farmacología , Antibacterianos/química , Polimerizacion , Triazinas/química
2.
Indian J Biochem Biophys ; 2012 Feb; 49(1): 49-54
Artículo en Inglés | IMSEAR | ID: sea-140218

RESUMEN

A novel phytase with a molecular mass of 14 kDa was isolated from fresh fruiting bodies of the common edible mushroom Volvariella volvacea (Straw mushroom). The isolation procedure involved successive chromatography on DEAE-cellulose, CM-cellulose, Affi-gel blue gel, Q-Sepharose and Superdex-75. The enzyme was a monomeric protein and was unadsorbed on DEAE-cellulose, CM-cellulose and Affi-gel blue gel, but was adsorbed on Q-Sepharose. The enzyme was purified 51.6-fold from the crude extract with 25.9% yield. Its N-terminal amino acid sequence GEDNEHDTQA exhibited low homology to the other reported phytases. The optimal pH and temperature of the purified enzyme was 5 and 45oC, respectively. The enzyme was quite stable over the pH range of 3.0 to 9.0 with less than 30% change in its activity, suggesting that it can be used in a very wide pH range. The enzyme exhibited broad substrate selectivity towards various phosphorylated compounds, but lacked antifungal activity against tested plant pathogens.


Asunto(s)
6-Fitasa/química , 6-Fitasa/aislamiento & purificación , Adaptación Fisiológica , Cromatografía DEAE-Celulosa/métodos , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Peso Molecular , Sefarosa/química , Alineación de Secuencia/métodos , Especificidad por Sustrato , Temperatura , Triazinas/química , Volvariella/enzimología
3.
Artículo en Inglés | IMSEAR | ID: sea-114070

RESUMEN

Waste Fe (III)/Cr (III) hydroxide was investigated for the removal of anionic dyes, namely acid brilliant blue (acidic dye) and procion red (reactive azo dye) from aqueous solution. In batch experiments, parameters studied include contact time, adsorbate concentration, pH, adsorbent dose and temperature. Adsorption followed Langmuir isotherm with adsorption capacity of 10.37 and 3.28 mg/g for acid brilliant blue and procion red, respectively. Adsorption kinetic studies showed second order with respect to acid brilliant blue and first order with respect to procion red. Thermodynamic parameters such as free energy, enthalpy and entropy of adsorption were also evaluated.


Asunto(s)
Adsorción , Compuestos de Cromo/química , Colorantes/química , Compuestos Férricos/química , Concentración de Iones de Hidrógeno , Residuos Industriales , Cinética , Temperatura , Triazinas/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos
4.
DARU-Journal of Faculty of Pharmacy Tehran University of Medical Sciences. 2004; 12 (2): 76-80
en Inglés | IMEMR | ID: emr-65644

RESUMEN

A Spectrophotometric method for determination of Cu [II] based on the complex formation with a new reagent 6-[2-naphthyl]-2,3-dihydro-as-triazine-3-thione[NDTT] is described. NDTT was synthesized based on the knowledge available for the preparation of 6-phenyl-2,3-dihydro-as-triazine-3-thione [PDTT]. Reaction of 2-acetylnaphthalene 1 with amyl nitrite gave 2-naphthylglyoxal aldoxime 2, which upon reaction with thiosemicarbazide yielded 6-[2-naphthyl]-2,3-dihydro-as-triazine-3-thione [NDTT] 3. NDTT produces a red complex with copper which is easily extractable with chloroform at pH>8 while the reagent is not extracted under these conditions. The absorption of the complex in the UV region [313 nm] is about 7 times greater than in the visible region [508 nm]. The mole ratio of the complex which is formed between Cu [II] and NDTT is 2:3, which was calculated by both the mole ratio and the continuous variation methods. The absorbance of the complex obeys Beer's law in the concentration range of 0.08-2 micro g Cu[II]/ml chloroform with r = 0.998 and detection limit of 13 ng/ml. This procedure can be carried out in the presence of many cations and anions in the presence or absence of the masking agents


Asunto(s)
Espectrofotometría , Triazinas/química , Indicadores y Reactivos
5.
Indian J Exp Biol ; 2003 Sep; 41(9): 991-1001
Artículo en Inglés | IMSEAR | ID: sea-62703

RESUMEN

Environmental contamination by nitro compounds is associated principally with the explosives industry. However, global production and use of explosives is unavoidable. The presently widely used nitro-explosives are TNT (Trinitrotoluene), RDX (Royal Demolition Explosive) and HMX (High Melting Explosive). Nevertheless, the problems of these nitro-explosives are almost parallel due to their similarities of production processes, abundance of nitro-explosives and resembling chemical structures. The nitro-explosives per se as well as their environmental transformation products are toxic, showing symptoms as methaemoglobinaemia, kidney trouble, jaundice etc. Hence their removal/degradation from soil/water is essential. Aerobic and anaerobic degradation of TNT and RDX have been reported, while for HMX anaerobic or anoxic degradation have been described in many studies. A multisystem involvement using plants in remediation is gaining importance. Thus the information about degradation of nitro-explosives is available in jigsaw pieces which needs to be arranged and lacunae filled to get concrete degradative schemes so that environmental pollution from nitro-explosives can be dealt with more successfully at a macroscale. An overview of the reports on nitro-explosives degradation, future outlook and studies done by us are presented in this review.


Asunto(s)
Biodegradación Ambiental , Contaminantes Ambientales/metabolismo , Contaminación Ambiental/prevención & control , Plantas/metabolismo , Microbiología del Suelo , Triazinas/química , Trinitrotolueno/química , Microbiología del Agua
6.
Indian J Biochem Biophys ; 2001 Feb-Apr; 38(1-2): 78-83
Artículo en Inglés | IMSEAR | ID: sea-27129

RESUMEN

T7 RNA polymerase (T7 RNAP) is an enzyme that utilizes ribonucleotides to synthesize the nascent RNA chain in a template-dependent manner. In this work we have studied the interaction of T7 RNAP with cibacron blue, an anthraquinone monochlorotriazine dye, and its effect on the function of the enzyme. T7 RNAP binds to the dye in a bi-phasic manner. The first phase of the binding is characterized by a high affinity (Kd in the nanomolar range) and reversible inactivation of the enzyme. The second binding site is the common substrate binding site. The association of the dye with T7 RNAP is a good model to understand the physiological significance of a high affinity binding of the initiating nucleotide, GTP, earlier reported from our laboratory. The results will be discussed to understand the role of the high affinity GTP binding.


Asunto(s)
Sitios de Unión , Unión Competitiva , ARN Polimerasas Dirigidas por ADN/química , Relación Dosis-Respuesta a Droga , Cinética , Plásmidos/metabolismo , Unión Proteica , Espectrometría de Fluorescencia , Triazinas/química , Uridina Trifosfato/metabolismo , Proteínas Virales
7.
Egyptian Journal of Chemistry. 1997; 40 (2): 117-28
en Inglés | IMEMR | ID: emr-107806

RESUMEN

Benzothieno [2, 3: 4', 5'] pyrimido [2, l-c] [1, 2, 4] triazines 2, 4 and 6 which represent a new fused heterocyclic ring system were synthesized by reacting 2-hydrazino-5, 6, 7, 8-tertrahydrobenzothieno [2, 3-d]-pyrimidin-4 [3H]-one [1] with phenacyl bromide, bromomalononitrile or chloroacetyl chloride, respectively. Condensation of 6 with aromatic aldehydes produced arylmethylene derivatives 7a, b. Reaction of 1 with phthalic anhydride afforded the phthalazine derivative 8. Also, compound 1 reacted with beta- diketones and with ethyl acetoacetate to produce the pyrazolyl 9a-c and pyrazolinone derivatives 11, respectively. Compound 11 condensed with aromatic aldehydes and coupled with diazotized aromatic amines to afford the corresponding arylmethylene and arylazo derivatives 12 and 13, respectively. All compounds were confirmed by IR, HNMR and analytical data


Asunto(s)
Pirimidinonas/química , Triazinas/química , Pirimidinas/síntesis química , Triazinas/síntesis química
8.
Egyptian Journal of Pharmaceutical Sciences. 1996; 37 (1-6): 329-339
en Inglés | IMEMR | ID: emr-40802

RESUMEN

Several new pyrazole, pyrazolo [5, 1-c]-1, 2, 4-triazine, pyrimidine and thiazole derivatives were synthesised by the reactions of 2-bromo-1-benzofurylglyoxal-2-[3-phenyl-pyrazol-5-yl]-hydrazone with a variety of reagents. Structures were established by elemental and spectral data


Asunto(s)
Triazinas/química , Pirimidinas/química , /química
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