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1.
Int J Mol Sci ; 22(3)2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33503808

RESUMO

Neutrophils produce hypochlorous acid (HOCl) as well as other reactive oxygen species as part of a natural innate immune response in the human body; however, excessive levels of HOCl can ultimately be detrimental to health. Recent reports suggest that betacyanin plant pigments can act as potent scavengers of inflammatory factors and are notably effective against HOCl. Comparison of the in vitro anti-hypochlorite activities of a novel betalain-rich red beetroot (Beta vulgaris L.) extract with its pure betalainic pigments revealed that the extract had the highest anti-hypochlorite activity, far exceeding the activity of all of the betalainic derivatives and selected reference antioxidants. This suggests that it may be an important food-based candidate for management of inflammatory conditions induced by excessive HOCl production. Among all pigments studied, betanidin exhibited the highest activity across the pH range.


Assuntos
Beta vulgaris/química , Betacianinas/química , Betalaínas/química , Corantes/química , Ácido Hipocloroso/química , Pigmentos Biológicos/química , Extratos Vegetais/química , Cromatografia Líquida , Humanos , Estrutura Molecular , Oxirredução , Hipoclorito de Sódio/química , Espectrometria de Massas por Ionização por Electrospray , Análise Espectral , Espectrometria de Massas em Tandem
3.
Niger J Clin Pract ; 23(3): 381-385, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32134039

RESUMO

Objectives: This study aimed to compare the effect of different solutions on the removal of orange-brown precipitate with or without ultrasonic activation. Materials and Methods: One hundred and twenty extracted maxillary anterior teeth were instrumented. In experimental groups (n = 10), canals were flushed with 17% EDTA, 10% citric acid, 1% phytic acid, 96% alcohol and distilled water either using syringe irrigation or ultrasonic activation, after creating orange-brown precipitate. Teeth were sectioned longitudinally and subjected to stereomicroscopic analysis. The amount of precipitate was scored and the data were analyzed (P = 0.05). Results: There were no differences detected among the tested solutions (P > 0.05). There was a significant difference between ultrasonically activated irrigation and syringe irrigation for EDTA and distilled water in coronal, middle portions (P < 0.05). Conclusions: Ultrasonic activation significantly improved the precipitate removal capacity of EDTA and DW. Tested solutions were similarly effective regarding the removal of the precipitate.


Assuntos
Clorexidina/química , Hipoclorito de Sódio/química , Sonicação/métodos , Dente/química , Humanos , Preparo de Canal Radicular
4.
Rev. ADM ; 77(1): 22-27, ene.-feb. 2020. ilus, graf
Artigo em Espanhol | LILACS | ID: biblio-1087921

RESUMO

Introducción: Hoy en día, la mayoría de los pacientes requieren tratamiento de ortodoncia fija convencional, la cual utiliza procedimientos adhesivos afines con la superficie amelodentinaria. Aunque existen diferentes técnicas adhesivas que pueden ofrecer adecuados niveles de resistencia al desalojo, el uso del hipoclorito de sodio (NaClO) como agente desproteinizante no ha sido bien definido en materiales de cementación en aparatología ortodóncica convencional. Objetivo: El objetivo de este estudio fue determinar los niveles de resistencia al desalojo con pruebas de microtensión y análisis topográfico con microscopia electrónica de barrido. Material y métodos: 20 bloques de esmalte bovino fueron expuestos superficialmente a soluciones acondicionadoras (ácido ortofosfórico al 37%) con y sin agente desproteinizante (NaClO al 5.25%); finalmente, brackets individuales de ortodoncia fueron cementados con sistemas adhesivos y resinas compuestas de casas comerciales (Ormco y 3M). Las pruebas de resistencia al desalojo fueron realizadas con una máquina de fuerzas universales y el análisis topográfico con microscopia electrónica de barrido. Resultados: El uso del NaClO al 5.25% y la marca Ormco tuvieron estadísticamente los mejores niveles de adhesión que el grupo sin desproteinización y la casa comercial 3M, respectivamente. La topografía adamantina expuesta al agente desproteinizante mostró características de superficie relacionadas con el patrón de grabado tipo I. Conclusión: El uso de un agente desproteinizante (NaClO 5.25%) así como una marca comercial (Ormco) en particular podrían definir el aumento en los niveles de adhesión en superficies adamantinas con aparatología ortodóncica convencional (AU)


Introduction: Nowadays, patients require conventional fixed orthodontic treatment, which uses adhesive procedures related to the dentinal denture surface. Although there are different adhesive techniques that can offer adequate levels of bonding resistance, the use of NaClO as a deproteinizing agent has not been well defined in cementing materials in conventional orthodontic appliances. Objective: The objective of this study was to determine the levels of bond resistance using micro tension tests and topographic analysis with scanning electron microscopy. Material and methods: Twenty-blocks of bovine enamel were exposed superficially to conditioning solutions (37% orthophosphoric acid) with and without deproteinizing agent (5.25% NaClO); finally, individual orthodontic brackets were cemented with adhesive systems and resin composites of different trademarks (Ormco and 3M). Bonding resistance tests were performed with a universal force machine and topographic analysis was made with scanning electron microscopy. Results: The use of 5.25% NaClO and the Ormco brand had statistically better levels of adhesion than the group without deproteinization and the 3M brand, respectively. Adamantine topography exposed to the deproteinizing agent showed surface characteristics related to the type I etching pattern. Conclusion: The use of a deproteinizing agent (NaClO 5.25%) as well as a trademark (Ormco) in particular conditions could define the increase in adhesion levels on adamantine surfaces with conventional orthodontic appliances (AU)


Assuntos
Hipoclorito de Sódio/química , Condicionamento Ácido do Dente , Colagem Dentária , Braquetes Ortodônticos , Esmalte Dentário/efeitos dos fármacos , Ácidos Fosfóricos , Propriedades de Superfície , Resistência à Tração , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Estudos Transversais , Análise Estatística , Resinas Compostas
5.
J Endod ; 46(2): 289-294, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31839410

RESUMO

INTRODUCTION: Mixtures of clodronate with sodium hypochlorite (NaOCl) better maintain free available chlorine (FAC) than etidronate-hypochlorite mixtures. This research aimed to compare organic tissue dissolution and residual FAC between clodronate and etidronate mixtures. Additionally, clodronate-hypochlorite mixtures lose no FAC over several hours. The second aim was to examine how well such mixtures dissolve organic material 6 hours from mixing. METHODS: Soon after mixing, porcine palatal mucosa samples were added to 32°C solutions containing 0.26 mol/L clodronate and 5% NaOCl (0.26 mol/L-5% NaOCl), 0.26 mol/L etidronate-5% NaOCl, 5% NaOCl, 0.26 mol/L clodronate, 0.26 mol/L etidronate, or phosphate-buffered saline. Weights and FAC, where applicable, were recorded initially and at 15 minutes. FAC was measured by iodometric titration. Secondly, 6 hours after mixing, mucosa was added to 0.26 mol/L clodronate-2.5% NaOCl, 2.5% NaOCl, 0.52 mol/L clodronate-5% NaOCl, 5% NaOCl, or phosphate-buffered saline. Sample weights at 0, 5, 10, and 15 minutes were recorded. Analysis of variance was used for statistical analyses (α < .05). RESULTS: Soon after mixing, 0.26 mol/L clodronate-5% NaOCl dissolved mucosa as well as 5% NaOCl and better than 0.26 mol/L etidronate-5% NaOCl compared with which it retained more FAC. At 6 hours after mixing, 0.26 mol/L clodronate-2.5% NaOCl dissolved organic material as well as 2.5% NaOCl. However, 0.52 mol/L clodronate-5% NaOCl dissolved less mucosa than 5% NaOCl. CONCLUSIONS: Soon after mixing, clodronate mixtures better dissolve organic material than etidronate mixtures and have higher residual FAC. Six hours from mixing, 0.26 mol/L clodronate-2.5% NaOCl mixtures dissolve organic material similarly to controls.


Assuntos
Ácido Clodrônico , Ácido Etidrônico , Irrigantes do Canal Radicular , Hipoclorito de Sódio , Animais , Ácido Clodrônico/química , Ácido Etidrônico/química , Irrigantes do Canal Radicular/química , Hipoclorito de Sódio/química , Solubilidade , Suínos
6.
Int J Biol Macromol ; 144: 615-623, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31843600

RESUMO

The structural modification of polysaccharides directly affects their physicochemical properties and applications. Dextran, a chained polysaccharide, consists of multiple d-glucose molecules with repetitive structures. In this study, the physicochemical properties of oxidized dextran (DO) at different concentrations of NaClO/NaBr and H2O2 were compared. The results showed that NaClO/NaBr oxidation is more conducive to the formation of carboxyl groups. Oxidized dextran with NaClO/NaBr (DOB) showed good iron (III) chelating ability, and the DOB­iron (III) complex (DOBIC) had an iron content of 28.31%. According to structural analysis, NaClO/NaBr (2 g/100 g of active chlorine) and H2O2 (4 g/100 g), respectively, oxidize the C1 and C2 hydroxyl groups of dextran to carboxyl groups and open the ring when DO and iron have the strongest chelation ability. The complex is indeed a chelate iron complex, and iron core is composed of iron oxyhydroxide or the ß-FeOOH mineral polymorph. These results indicate that DOBIC is expected to be a good iron supplement or food additive to strengthen iron.


Assuntos
Brometos/química , Complexos de Coordenação/química , Dextranos/química , Peróxido de Hidrogênio/química , Quelantes de Ferro/química , Compostos de Sódio/química , Hipoclorito de Sódio/química , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Ferro/química , Cinética , Minerais/química , Peso Molecular , Oxirredução , Relação Estrutura-Atividade
7.
Microsc Res Tech ; 83(2): 186-195, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31701615

RESUMO

This study evaluated the effect of 10% sodium hypochlorite (NaOCl) as deproteinizing agent and storage media on bond strength (BS) of two etch-and-rinse adhesive systems to dentin. Twenty-eight sound extracted human third molars were divided in four groups (n = 7), according to dentin treatment (conventional etching or etching followed by 10% NaOCl application) and adhesive systems (GB-Gluma 2Bond and OS-One-Step). After dentin treatments and adhesive application, a composite block was built-up on dentin surface and teeth were serially sectioned to obtain bonded sticks specimens. The sticks were submitted to three aging conditions: (24H) 24 hr in water (immediate), (SH) 3 hr of NaOCl accelerated-aging or (1Y) 1 year of water storage. Afterward, submitted to microtensile bond strength test (µTBS), failure modes and adhesive interfaces analyzes. Data were analyzed by two-way analysis of variance (ANOVA) and Tukey's test (α = .05). Dentin deproteinization before bonding significantly reduced µTBS for GB-treated group (p < .05), regardless the aging conditions. Water storage for 1 year (1Y) and NaOCl accelerated-aging (SH) decreased µTBS for both adhesives. Yet, the groups stored in NaOCl (SH) exhibited the lowest BS results (p < .05). Bond strength of deproteinized dentin was dependent on the adhesive system composition and NaOCl accelerated-aging promoted decreased bond strength and further degradation than water storage for 1 year.


Assuntos
Adesivos/química , Dentina/química , Dente Serotino , Hipoclorito de Sódio/química , Colagem Dentária , Análise do Estresse Dentário , Humanos , Teste de Materiais , Resistência à Tração , Água
8.
Ultrason Sonochem ; 61: 104854, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31739168

RESUMO

The objective of this study was to evaluate the differences in ex-situ (starch treated by ultrasonication and oxidation sequentially, U-OS) and in-situ (starch treated by ultrasonication and oxidation simultaneously, UOS) ultrasonic assisted oxidation process of corn starch, which were studied in contrast to the traditional oxidized starches (OS). Fourier-transform infrared spectra confirmed the successful oxidation of all modified starches samples. In comparison to the OS, the carboxyl contents of U-OS and UOS increased by 56% and 112%, respectively. The same increase trend was also found for the carbonyl contents. The significance raise was attributed to the great increase of pores and specific surface areas in the starch granule after ultrasonic irradiation which promoted the penetration of the sodium hypochlorite into the starch granules with higher chances for chemical reactions. SEM and pore size distribution characterizations further verified this result. However, the method of in-situ ultrasonic assisted oxidation can simultaneously accelerate the increase of pores and the penetration process. Consequently, the starches with higher oxidation degree can be more efficiently prepared by the strategy of in-situ ultrasonic assisted oxidation.


Assuntos
Amido/química , Ondas Ultrassônicas , Oxirredução , Hipoclorito de Sódio/química
9.
BMC Biotechnol ; 19(Suppl 2): 91, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31847839

RESUMO

BACKGROUND: The symbiosis between the olive fruit fly, Bactrocera oleae, and Candidatus Erwinia dacicola has been demonstrated as essential for the fly's larval development and adult physiology. The mass rearing of the olive fruit fly has been hindered by several issues, including problems which could be related to the lack of the symbiont, presumably due to preservatives and antibiotics currently used during rearing under laboratory conditions. To better understand the mechanisms underlying symbiont removal or loss during the rearing of lab colonies of the olive fruit fly, we performed experiments that focused on bacterial transfer from wild female flies to their eggs. In this research, eggs laid by wild females were treated with propionic acid solution, which is often used as an antifungal agent, a mixture of sodium hypochlorite and Triton X, or water (as a control). The presence of the bacterial symbiont on eggs was evaluated by real-time PCR and scanning electron microscopy. RESULTS: DGGE analysis showed a clear band with the same migration behavior present in all DGGE profiles but with a decreasing intensity. Molecular analyses performed by real-time PCR showed a significant reduction in Ca. E. dacicola abundance in eggs treated with propionic acid solution or a mixture of sodium hypochlorite and Triton X compared to those treated with water. In addition, the removal of bacteria from the surfaces of treated eggs was highlighted by scanning electron microscopy. CONCLUSIONS: The results clearly indicate how the first phases of the colony-establishment process are important in maintaining the symbiont load in laboratory populations and suggest that the use of products with antimicrobial activity should be avoided. The results also suggest that alternative rearing procedures for the olive fruit fly should be investigated.


Assuntos
Erwinia/isolamento & purificação , Olea/parasitologia , Tephritidae/fisiologia , Animais , Erwinia/genética , Feminino , Masculino , Microscopia Eletrônica de Varredura , Octoxinol/química , Óvulo/efeitos dos fármacos , Óvulo/microbiologia , Propionatos/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Comportamento Sexual Animal , Hipoclorito de Sódio/química , Hipoclorito de Sódio/farmacologia , Simbiose , Tephritidae/microbiologia
10.
Sci Rep ; 9(1): 19955, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882630

RESUMO

There is increasing demand for safe and effective sanitizers for irrigation water disinfection to prevent transmission of foodborne pathogens to fresh produce. Here we compared the efficacy of pH-neutral electrolyzed oxidizing water (EOW), sodium hypochlorite (NaClO) and chlorine dioxide (ClO2) against single and mixed populations of E. coli, Listeria and Salmonella under a range of pH and organic matter content. EOW treatment of the mixed bacterial suspension resulted in a dose-dependent (<1 mg/L free chlorine), rapid (<2 min) and effective (4-6 Log10) reduction of the microbial load in water devoid of organic matter under the range of pH conditions tested (pH, 6.0, 7.0, 8.4 and 9.2). The efficacy of EOW containing 5 mg/L free chlorine was unaffected by increasing organic matter, and compared favourably with equivalent concentrations of NaClO and ClO2. EOW at 20 mg/L free chlorine was more effective than NaClO and ClO2 in reducing bacterial populations in the presence of high (20-100 mg/L) dissolved organic carbon, and no regrowth or metabolic activity was observed for EOW-treated bacteria at this concentration upon reculturing in rich media. Thus, EOW is as effective or more effective than other common chlorine-based sanitizers for pathogen reduction in contaminated water. EOW's other characteristics, such as neutral pH and ease of handling, indicate its suitability for fresh produce sanitation.


Assuntos
Desinfetantes/análise , Desinfetantes/química , Desinfecção/métodos , Antibacterianos/análise , Antibacterianos/química , Cloretos/química , Cloro/química , Compostos Clorados/química , Eletrólise/métodos , Escherichia coli O157/crescimento & desenvolvimento , Manipulação de Alimentos/métodos , Listeria/crescimento & desenvolvimento , Oxirredução , Óxidos/química , Salmonella/crescimento & desenvolvimento , Hipoclorito de Sódio/química , Água/química , Purificação da Água/métodos
11.
Huan Jing Ke Xue ; 40(7): 3208-3215, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854720

RESUMO

To study the effect of on-line NaClO backwashing on the microbial community structure of membrane bioreactor (MBR) systems, a reversed A2O-MBR reactor was used to monitor system performance, membrane fouling, and microbial community structure. Measurements were made during the stabilization stage, the on-line pure water backwashing stage, and the on-line NaClO backwashing stage. The results showed that key system performance indicators during NaClO backwashing stage, such as COD, ammonia nitrogen, and TN treatment efficiency, were similar to previous stages. The average membrane fouling rate during the on-line pure water backwashing period was lower than that of the stable stage, while the membrane fouling rate increased during the on-line NaClO backwashing stage, and EPS concentration was the highest and membrane fouling was aggravated. The results of the Chao index, Simpson index, and Shannon index showed that the microbial diversity in the aerobic tank sludge remained almost stable after on-line NaClO backwashing, while the abundance of cake layer sludge increased slightly, but the microbial diversity decreased significantly. Proteobacteria was the main microbial phylum in both the aerobic tank and cake layer sludge, followed by Bacteroidetes. After on-line NaClO backwashing, the relative abundance of Proteobacteria and Bacteroides in the aerobic tank sludge did not change notably, but the composition of filter cake sludge changed significantly. Proteobacteria that possess resistance to chlorine disinfectant increased from 53.4% to 77.8%, while Bacteroides decreased from 33.44% to 14.5%. After on-line NaClO backwashing, the composition of the microbial community in aerobic tank and cake layer was similar. Azospira and Comamonadaceaea also increased significantly after NaClO backwashing. Microbial species that can tolerate NaClO treatment may be the main cause of membrane fouling.


Assuntos
Bacteroidetes , Reatores Biológicos/microbiologia , Proteobactérias , Hipoclorito de Sódio/química , Membranas Artificiais , Nitrogênio , Esgotos/microbiologia
12.
J Biomol Tech ; 30(4): 58-63, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31598098

RESUMO

There are several methods, both chemical and enzymatic, to release N-linked glycans for structural characterization. One of the most common enzymatic release methods is the use of peptide:N-glycosidase F (PNGase F). A less expensive and quicker alternative has been reported for the release of N-linked glycans chemically using sodium hypochlorite (NaOCl), which hydrolyzes the peptide-glycan bond, yielding the intact glycan with a free reducing terminus. Here, we quantitatively analyzed the efficiency of the NaOCl release protocol compared with the PNGaseF release protocol for small-scale analysis (300 µg) using liquid chromatography-single reaction monitoring-mass spectrometry. We determined that the relative glycan composition of released N-linked glycans from the NaOCl protocol is similar to a typical PNGase F protocol, but the absolute recovery of N-linked glycans is significantly lower with the chemical procedure.


Assuntos
Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase/química , Polissacarídeos/química , Hipoclorito de Sódio/química , Cromatografia Líquida , Glicômica , Glicoproteínas/química , Polissacarídeos/análise , Polissacarídeos/isolamento & purificação , Espectrometria de Massas em Tandem
13.
PLoS One ; 14(10): e0223117, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31603899

RESUMO

Anthracyclines are a class of pharmaceuticals used in cancer treatment have the potential to negatively impact the environment. To study the possibilities of anthracyclines (represented by pirarubicin and valrubicin) removal, chemical inactivation using NaOH (0.01 M) and NaClO (5%) as decontamination agents and adsorption to powdered nanocrystalline titanium dioxide (TiO2) were compared. The titanium dioxide (TiO2) nanoparticles were prepared via homogeneous precipitation of an aqueous solution of titanium (IV) oxy-sulfate (TiOSO4) at different amount (5-120 g) with urea. The as-prepared TiO2 samples were characterized by XRD, HRSEM and nitrogen physisorption. The adsorption process of anthracycline cytostatics was determined followed by high-performance liquid chromatography coupled with mass spectrometry (LC-MS) and an in-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) technique. It was found that NaClO decomposes anthracyclines to form various transformation products (TPs). No TPs were identified after the reaction of valrubicin with a NaOH solution as well as in the presence of TiO2 nanoparticles. The best degree of removal, 100% of pirarubicin and 85% of valrubicin, has been achieved in a sample with 120 grams of TiOSO4 (TIT120) and TiO2 with 60 grams (TIT60), respectively.


Assuntos
Citostáticos/química , Doxorrubicina/análogos & derivados , Nanoestruturas/química , Titânio/química , Poluentes Químicos da Água/química , Adsorção , Cristalização , Citostáticos/isolamento & purificação , Descontaminação/métodos , Doxorrubicina/química , Doxorrubicina/isolamento & purificação , Hidrólise , Tamanho da Partícula , Hidróxido de Sódio/química , Hipoclorito de Sódio/química , Propriedades de Superfície , Poluentes Químicos da Água/isolamento & purificação
14.
Artigo em Inglês | MEDLINE | ID: mdl-31635217

RESUMO

Chemical reaction of main polymer and additive with oxidative cleaning agents plays an important role in aging of polymeric membrane for water and wastewater treatment. As a green and powerful oxidant, hydrogen peroxide (H2O2) can achieve good cleaning efficacy under alkaline condition, but its influence on membrane aging was poorly understood. In this study, degradation of polyethersulfone (PES) membrane due to H2O2 exposure under alkaline condition (pH 9 and 11) was holistically investigated by humic acid (HA) filtration experiments and multiple membrane characterization techniques, with sodium hypochlorite (NaClO) aging examined as a comparison. Membrane permeability and HA retention rate was hardly changed by H2O2 aging at an exposure dose of 500 g·h/L, whereas NaClO aging led to substantial increase of membrane permeability and significant decrease of retention ability. Meanwhile, H2O2 aging slightly increased fouling propensity with HA filtration, while NaClO aging resulted in more serious fouling. ATR-FTIR and XPS analysis revealed much less degradation of PES and hydrophilic additive by H2O2 than that by NaClO, and membrane morphology and surface properties were characterized to explain the variation of filtration performance. Overall, compared with cleaning with NaClO, membrane degradation can be minimized by cleaning with H2O2.


Assuntos
Peróxido de Hidrogênio/química , Polímeros/química , Hipoclorito de Sódio/química , Sulfonas/química , Ultrafiltração , Substâncias Húmicas/análise , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais
15.
Adv Clin Exp Med ; 28(10): 1311-1319, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31469948

RESUMO

BACKGROUND: Endodontic treatment is one of the most widely performed procedures in a dental office. New techniques for enhancing the effectiveness of irrigants are being introduced into the dental market. It is crucial to choose a proper method to obtain the highest possible long-term success of performed endodontic treatment. Sodium hypochlorite (NaOCl) appears to be one of the most common and profitable solutions for root canal irrigation. The activation of a solution may be analyzed in 2 fields, physical - turbulence of flow, and chemical - disintegration of irrigant molecules into very active radicals that improve its activity. While the physical alternations of irrigant flow with different techniques are widely studied, there are not many attempts to approach the subject in chemical terms. OBJECTIVES: The aim of the study was to compare the chemical effectiveness of 2 methods of NaOCl activation: ultrasonics vs the Self-Adjusting File system (SAF) as an adjunct to increase the efficacy of the irrigant. MATERIAL AND METHODS: The level of activation was evaluated via a reaction of the activated NaOCl samples, with 9-fluorenol as the starting organic material. The model reaction is based on the oxidation of 9-fluorenol to 9-fluorenon. The evaluation was performed using 1H nuclear magnetic resonance (NMR) spectroscopy, comparing the spectra obtained for the examined mixtures. RESULTS: Nuclear magnetic resonance studies show that the use of ultrasonics resulted in increased chemical degradation of NaOCl as compared to the SAF system and non-agitated samples. The prevalence of chemical activation in the ultrasonic group over the SAF group was almost 3 times higher, 3.11 to 1.20, respectively. The Kruskal-Wallis rank sum test revealed there is a statistically significant difference in distributions between the groups. CONCLUSIONS: Both SAF and ultrasonics activate NaOCl. Ultrasonic agitation provided higher chemical activation of NaOCl solution than the SAF. The use of ultrasonic agitation of NaOCl in endodontic treatment will allow us to obtain better long-term clinical results.


Assuntos
Cavidade Pulpar/efeitos dos fármacos , Irrigantes do Canal Radicular/administração & dosagem , Preparo de Canal Radicular/instrumentação , Hipoclorito de Sódio/administração & dosagem , Irrigação Terapêutica/métodos , Humanos , Irrigantes do Canal Radicular/química , Preparo de Canal Radicular/métodos , Hipoclorito de Sódio/química
16.
Molecules ; 24(17)2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31450724

RESUMO

The highly prescribed antidepressant, citalopram, as one of newly emerging pollutants, has been frequently detected in the aquatic environment. Citalopram oxidation was examined during sodium hypochlorite (NaOCl) and chlorine dioxide (ClO2) chlorination processes since conventional wastewater treatment plants cannot remove citalopram effectively. Citalopram has been demonstrated to form N-nitrosodimethylamine (NDMA) during chlorination in our previous study. Further investigation on NDMA formation kinetics was conducted in the present study. Influences of operational variables (disinfectant dose, pH value) and water matrix on citalopram degradation, as well as NDMA generation, were evaluated. The results indicated high reactivity of citalopram with NaOCl and ClO2. NDMA formation included two stages during CIT oxidation, which were linear related with reaction time. NaOCl was more beneficial to remove CIT, but it caused more NDMA formation. Increasing disinfectant dosage promoted citalopram removal and NDMA formation. However, no consistent correlation was found between citalopram removal and pH. Contrary to the situation of citalopram removal, NDMA generation was enhanced when citalopram was present in actual water matrices, especially in secondary effluent. DMA, as an intermediate of citalopram chlorination, contributed to NDMA formation, but not the only way.


Assuntos
Compostos Clorados/química , Citalopram/química , Oxirredução , Óxidos/química , Hipoclorito de Sódio/química , Dimetilnitrosamina/química , Desinfetantes/farmacologia , Halogenação , Concentração de Íons de Hidrogênio , Cinética , Estrutura Molecular , Oxirredução/efeitos dos fármacos , Água/química
17.
Braz Oral Res ; 33: e057, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365704

RESUMO

The aim of this study was to evaluate the effect of peracetic acid (PAA) as a single irrigant on the smear layer, on the intraradicular dentinal bond strength, and on the penetrability of an epoxy-based resin sealer into the dentinal tubules. A total of 120 roots were distributed into 4 groups according to the irrigant used in root canal preparation: 1% PAA (PAA); 2.5% NaOCl followed by final irrigation with 17% EDTA and 2.5% NaOCl (NaOCl-EDTA-NaOCl); 2.5% NaOCl (NaOCl); and saline solution (SS). The smear layer was evaluated using scanning electron microscopy. The bond strength of an epoxy-based resin sealer (AH Plus) to root dentin was evaluated by the push-out test and penetrability of the sealer into dentinal tubules was observed by confocal laser microscopy. The results were analyzed by the Kruskal-Wallis and the Dunn post-test (α = 0.05). The use of 1% PAA as single root canal irrigant provided smear layer removal and improved the penetrability and bond strength of AH Plus to root dentin in a manner similar to that of the NaOCl-EDTA-NaOCl group (p > 0.05). The NaOCl and SS groups had higher values of smear layer and lower values of sealer penetrability and dentin bond strength than the PAA and NaOCl-EDTA-NaOCl groups (p < 0.05). Thus, 1% PAA has the potential to be used as a single irrigant in root canals.


Assuntos
Cavidade Pulpar/efeitos dos fármacos , Dentina/efeitos dos fármacos , Resinas Epóxi/química , Ácido Peracético/química , Materiais Restauradores do Canal Radicular/química , Irrigantes do Canal Radicular/química , Camada de Esfregaço/química , Colagem Dentária/métodos , Cavidade Pulpar/química , Dentina/química , Ácido Edético/química , Humanos , Teste de Materiais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Valores de Referência , Reprodutibilidade dos Testes , Hipoclorito de Sódio/química
18.
J Appl Oral Sci ; 27: e20180420, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31166549

RESUMO

OBJECTIVE: This in vitro study aimed to compare the efficacy of irrigants using various irrigation activation methods to the push-out bond strengths of fiber post to root canal luted with self-adhesive resin cement (SARC). METHODOLOGY: Forty-eight decoronated human canines were used. The specimens were divided into four groups corresponding with the post-space irrigation process and were treated as follows: distilled water (DW) (Control) group received 15 mL of DW; sodium hypochlorite (NaOCl)+ethylenediaminetetraacetic acid (EDTA) group was treated with 5 mL of 5.25% NaOCl, 5 mL of 17% EDTA, and 5 mL of DW; passive ultrasonic irrigation (PUI) group was treated with 5 mL of 5.25% NaOCl, 5 mL of 17% EDTA, and 5 mL of DW, and each irrigant was agitated with an ultrasonic file; and laser activated irrigation (LAI) group was treated with 5 mL of 5.25% NaOCl, 5 mL of 17% EDTA, and 5 mL of DW, and each irrigant was irradiated with Nd: YAG laser. Fiber posts were luted with SARC, and a push-out test was performed. Data was analyzed using one-way analysis of variance and Tukey HSD test. RESULTS: The bond strength values for the groups obtained were as follows: Control (10.04 MPa), NaOCl+EDTA (11.07 MPa), PUI (11.85 MPa), and LAI (11.63 MPa). No statistically significant differences were found among all experimental groups (p>0.05). The coronal (12.66 MPa) and middle (11.63 MPa) root regions indicated a significantly higher bond strength compared with the apical (9.16 MPa) region (p<0.05). CONCLUSIONS: Irrigant activation methods did not increase the bond strength of fiber post to canal.


Assuntos
Lasers de Estado Sólido , Técnica para Retentor Intrarradicular , Irrigantes do Canal Radicular/química , Irrigantes do Canal Radicular/efeitos da radiação , Autocura de Resinas Dentárias/métodos , Terapia por Ultrassom/métodos , Análise de Variância , Cavidade Pulpar/efeitos dos fármacos , Cavidade Pulpar/efeitos da radiação , Falha de Restauração Dentária , Dentina/efeitos dos fármacos , Dentina/efeitos da radiação , Ácido Edético/química , Ácido Edético/efeitos da radiação , Humanos , Teste de Materiais , Valores de Referência , Reprodutibilidade dos Testes , Preparo de Canal Radicular/métodos , Hipoclorito de Sódio/química , Hipoclorito de Sódio/efeitos da radiação , Propriedades de Superfície
19.
Biomed Mater Eng ; 30(3): 279-285, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30988236

RESUMO

The objective of this study was to evaluate the effect of sodium hypochlorite and chlorhexidine solutions and their inactivating agents on the push-out bond strength of mineral trioxide aggregate (MTA). One hundred fifty root slices were prepared and their root canal spaces were enlarged using diamond burs. MTA was prepared and compacted to root canal spaces. The samples were randomly separated to 4 groups that would be immersed into the selected solutions (5.25% sodium hypochlorite (NaOCl), 5.25% NaOCl and sodium thiosulfate, 2% chlorhexidine (CHX), 2% CHX and a mixture of Tween 80 and 0.3% L-alfa-lecithin) and a control group (n = 30). Push-out bond strength of each specimen was tested with universal testing machine. The data was analyzed by one-way analysis of variance and Tukey tests. There were no significant differences between the push-out bond strength values of the irrigation groups and the control group. A significant difference was found between the push-out bond strength values of NaOCl-Sodium thiosulfate and CHX-L-alpha-lecithin groups. Contact with NaOCl and its neutralizing agent with MTA after 10 minutes of setting period increased the push-out bond strength of MTA. On the other hand, any contact with CHX alone or with subsequent application using L-alfa-lecithin should be avoided since that might decrease the push-out bond strength of freshly mixed MTA.


Assuntos
Compostos de Alumínio/química , Compostos de Cálcio/química , Clorexidina/química , Materiais Dentários/química , Óxidos/química , Irrigantes do Canal Radicular/química , Silicatos/química , Hipoclorito de Sódio/química , Análise do Estresse Dentário/instrumentação , Combinação de Medicamentos , Desenho de Equipamento , Humanos , Lecitinas/química , Teste de Materiais/instrumentação , Polissorbatos/química , Irrigação Terapêutica
20.
Dokl Biochem Biophys ; 484(1): 37-41, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31012009

RESUMO

Oxidation of fibrinogen with hypochlorite inhibited the fibrin network self-assembly even at the lowest concentration of the oxidant. The analysis of the results of protein electrophoresis at this hypochlorite concentration showed the absence of fragmentation of the protein and covalent cross-linking of its chains. The study of the areas responsible for the conversion of fibrinogen into fibrin by mass spectrometry showed that they are not subject to oxidative damage. However, we identified oxidized amino acid residues, which could affect the protofibril aggregation.


Assuntos
Fibrina/química , Fibrinogênio/química , Hipoclorito de Sódio/química , Feminino , Humanos , Masculino , Oxirredução
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