Effects of the application of sodium ascorbate after in-office bleaching on the penetration of hydrogen peroxide, color change, and microtensile bond strength.

This study aimed to evaluate the effects of the application of 10% sodium ascorbate (SA) after in-office bleaching on the penetration of hydrogen peroxide (HP) into the pulp chamber, color change, and microtensile bond strength (µTBS) to the resin-enamel interface. Thirty premolars and thirty molars were randomly divided into three groups (n = 20 each). One group was exposed to deionized water (negative control). The other two groups were bleached with 35% HP in a single session for 3x15 minutes for each application. However, in only one of them, SA was applied for 10 minutes after bleaching. After, the concentration (µg/mL) of HP in each pulp chamber was evaluated by UV-Vis spectrophotometry. Color changes (ΔEab, ΔE00, and ΔWID) were evaluated with a digital spectrophotometer before and in the first week after bleaching. After treatment, molars were restored and sectioned to obtain resin-enamel interface sticks for µTBS at a crosshead speed of 1 mm/min until failure. The HP concentration and µTBS data were analyzed using one-way ANOVA and Tukey tests, and color changes were analyzed by t-tests (α = 0.05). SA application significantly improved the µTBS values and reduced the HP concentrations within the pulp chambers (p < 0.0001). The application of SA significantly interfered with the color changes after bleaching when compared to the control group (p < 0.05). Application of 10% SA after in-office bleaching successfully reduced the penetration of HP into the pulp chamber; however, it decreased color change.

Effects of the application of sodium ascorbate after in-office bleaching on the penetration of hydrogen peroxide, color change, and microtensile bond strength

Abstract This study aimed to evaluate the effects of the application of 10% sodium ascorbate (SA) after in-office bleaching on the penetration of hydrogen peroxide (HP) into the pulp chamber, color change, and microtensile bond strength (µTBS) to the resin-enamel interface. Thirty premolars and thirty molars were randomly divided into three groups (n = 20 each). One group was exposed to deionized water (negative control). The other two groups were bleached with 35% HP in a single session for 3x15 minutes for each application. However, in only one of them, SA was applied for 10 minutes after bleaching. After, the concentration (µg/mL) of HP in each pulp chamber was evaluated by UV-Vis spectrophotometry. Color changes (ΔEab, ΔE00, and ΔWID) were evaluated with a digital spectrophotometer before and in the first week after bleaching. After treatment, molars were restored and sectioned to obtain resin-enamel interface sticks for µTBS at a crosshead speed of 1 mm/min until failure. The HP concentration and µTBS data were analyzed using one-way ANOVA and Tukey tests, and color changes were analyzed by t-tests (α = 0.05). SA application significantly improved the µTBS values and reduced the HP concentrations within the pulp chambers (p < 0.0001). The application of SA significantly interfered with the color changes after bleaching when compared to the control group (p < 0.05). Application of 10% SA after in-office bleaching successfully reduced the penetration of HP into the pulp chamber; however, it decreased color change.

Resumo Este estudo teve como objetivo avaliar os efeitos da aplicação do ascorbato de sódio a 10% (AS) depois do clareamento em consultório na penetração do peróxido do hidrogênio (PH) na câmara pulpar, mudança de cor e resistência de união (RU) da interface resina-esmalte. Trinta pré-molares e trinta molares foram divididos aleatoriamente em três grupos (n = 20). Um grupo foi exposto em água deionizada (controle negativo). Os outros dois grupos foram clareados com 35% PH numa única sessão de 3x15 minutos para cada aplicação. Porém, só um grupo recebeu AS durante 10 minutos depois do clareamento. Depois, a concentração (µg/mL) do PH no interior de cada câmara pulpar foi avaliado com espectrofotometria UV-Vis. A mudança de cor (ΔEab, ΔE00 and ΔWID) foi avaliada como espectrofotômetro digital antes e depois de uma semana do clareamento. Após de cada tratamento, os molares foram restaurados e seccionados em espécimes com interface resina-esmalte para o teste de RU por microtração a uma velocidade de 1 mm/min até a fratura. Os dados da concentração de PH e RU foram analisados usando ANOVA de uma via e teste de Tukey, e a mudança de cor com o teste t (α = 0.05). A aplicação de AS melhorou significativamente a RU e reduziu a concentração de PH na câmara pulpar (p < 0.0001). A aplicação de AS interferiu significativamente na mudança de cor depois do clareamento comprado com o grupo controle (p < 0.05). A aplicação de SA a 10% depois do clareamento em consultório reduziu significativamente a penetração do PH na câmara pulpar e interferiu na mudança de cor.

Protective effect of the medicinal herb infusion "horchata" against oxidative damage in cigarette smokers: An ex vivo study.

Cigarette smoking has been associated with an increase in oxidative stress (OS) and is considered a predisposing factor to chronic noncommunicable diseases, whilst dietary antioxidants has been proposed as an alternative to cope with this oxidative stress. In this study, 20 smokers and 20 non-smokers were studied with the aim of determining their antioxidant status, as well as the ability of an infusion of 23 medicinal plants, to counteract the damage caused by OS. The plasma, red blood cells (RBCs) and polymorphonuclear cells (PBMCs) of both groups were incubated or not with the horchata infusion extract and then the OS markers, genotoxicity, nanostructure of RBCs membrane and genes related to oxidative responses and cellular functionality were evaluated. Up to 33 different compounds, mainly quercetin glycosides, were identified in the extract. A significant deterioration in the antioxidant status in smokers compared to non-smokers was found. The horchata infusion extract improved the nanostructure of RBCs and DNA damage, as well as the activity of the endogenous antioxidant enzymes and markers of oxidative damage to lipid, and proteins in plasma, RBCs and PBMCs in both groups, whilst no significant changes were found in the expression of different genes related to OS response.

Pechiche (Vitex Cymosa Berteo ex Speng), a Nontraditional Fruit from Ecuador, is a Dietary Source of Phenolic Acids and Nutrient Minerals, in Addition to Efficiently Counteracting the Oxidative-Induced Damage in Human Dermal Fibroblasts.

Pechiche fruits (Vitex cymosa Berteo ex Speng) from Ecuador were studied to determine their phenolic acid profile, nutrient minerals and capacity to protect primary human dermal fibroblasts (HDFa) against oxidative-induced damage. Up to five phenolic acids were identified, with homovanillic acid as the main one. Vitamin C, ß-carotene and lutein were also determined. Phosphorus and potassium were the main macrominerals, while iron was the principal micromineral. HDFa were preincubated with a crude pechiche extract (PCext) and then subjected to oxidative stress. The activity of five antioxidant enzymes, intracellular reactive oxygen species (ROS) and ATP levels and lipid peroxidation and protein oxidation were used as markers of oxidative damage. Preincubation with PCext for 24 h allowed for the significant reduction of intracellular ROS levels, improved the intracellular ATP levels and protected lipids and proteins against oxidative damage (p 0.05). Additionally, preincubation with PCext was also able to significantly (p < 0.05) improve the activity of the antioxidant enzymes catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase and glutathione transferase, compared to the stressed group without pretreatment. The results obtained in this study suggest the potential of pechiche as a source of bioactive compounds, as well as its beneficial effect against oxidative stress.

Bioactive compounds and antioxidant capacity of Chuquiraga jussieui J.F.Gmel from the highlands of Ecuador.

Chuquiraga jussieui J.F.Gmel is grown between 3000 and 5000 meters above sea level throughout the Andean region of Ecuador and used by the indigenous populations of the Andes for medicinal purposes. Here, we determined the total phenolic, flavonoids, vitamin C and carotenoids content of the leaves and flowers of Ch. jussieui J.F.Gmel from different highlands of Ecuador as well as the capacity of a crude methanolic extract from the both parts of the plant to scavenge free radicals and protect red blood cell membranes from lipid oxidation. The leaves showed a high bioactive compound content in comparison to the flowers. The crude extract from the leaves proved to be more effective than the flowers in reducing iron and scavenging the DPPH, O2- and H2O2 radicals, as well as in protecting cellular membrane against lipid oxidation, demonstrating that Ch. jussieui J.F.Gmel represents an important source of bioactive compounds with relevant healthy properties.

Chemical Composition and Antioxidant Activity of the Main Fruits Consumed in the Western Coastal Region of Ecuador as a Source of Health-Promoting Compounds.

We studied 19 different tropical fruits traditionally consumed in the coastal lowlands of Ecuador to determine their chemical composition and antioxidant activity. Carambola (Averrhoa carambola L.) had the highest total phenolic, flavonoid, and total antioxidant capacity values, whereas guava fruits (Psidium guajava L.) had the highest vitamin C values. The main organic acids identified were lactic, citric, and acetic acids, and the highest amount of lactic acid was found in soursop fruits (Annona muricata L.), whereas Ecuadorian ivory palm (Phytelephas aequatorialis Spruce) and guava fruits had the highest acetic acid content. Guava also had the highest citric acid content; the highest concentration of oxalic acid was found in carambola. In terms of sugar content, giant granadilla (Passiflora quadrangularis L.) had the highest values of glucose, and red mombin (Spondias mombin L.) had the largest values for fructose and guava for sucrose. Chili pepper (Capsicum chinense Jacq) proved to be the main source of carotenoids, lutein, and ß-carotene, anthocyanins, and vitamin C. The results here increase our knowledge regarding the composition of the main fruits consumed on the west coast of Ecuador to facilitate recommendations as potential sources of health-promoting compounds.

Anti-inflammatory effect of the medicinal herbal mixture infusion, Horchata, from southern Ecuador against LPS-induced cytotoxic damage in RAW 264.7 macrophages.

The phytochemical composition and the antioxidant and anti-inflammatory activities of a mixture of 23 plants, named Horchata, traditionally consumed in Ecuador, have been evaluated. The study was carried out using the hydroalcoholic extract (HHext) and infusion (IHext) of the horchata plant mixture. It was verified that thermal treatment affected the contents of vitamin C and carotenoids, but hardly those of polyphenols, which would be the main bioactive compounds in the infusion, the common form of preparation of horchata for consumption. Among phenolic compounds, caffeoylquinic acids, flavones and flavonols (mostly quercetin glycosides) were prominent. Both HHext and IHext extracts managed to protect RAW 264.7 macrophages against LPS-induced cytotoxic damage, increasing the levels of endogenous antioxidant enzymes and modulating the production of pro-inflammatory and anti-inflammatory cytokines. Greater protective effects were obtained for HHext compared to IHext, which was in agreement with its higher content of phenolic compounds favoured by a more efficient extraction in the hydroalcoholic medium. Nonetheless, the infusion still maintained a significant antioxidant and anti-inflammatory activity, which would support the protective effects on health traditionally attributed to its consumption by the population.

Chemical Composition and Antioxidant Activity of the Main Fruits, Tubers and Legumes Traditionally Consumed in the Andean Regions of Ecuador as a Source of Health-Promoting Compounds.

Thirteen fruits, eight legumes and three tubers consumed in the Andean regions of Ecuador were studied to determine their bioactive compounds, organic acids, sugars content, total antioxidant capacity, as well as to determine which among them showed the greatest contribution in terms of antioxidant activity and which compounds contributed to it. Among fruits, taxo fruits (Passiflora mollissima (Kunth) L.H. Bailey) presented the highest values of total phenolic, carotene content, and total antioxidant capacity. The ají ratón (Capsicum chinense Jacq) showed the highest content of vitamin C. Taxo showed the highest content of ß carotene, whilst lycopene was identified only in guayaba fruits (Psidium guajava L.) and ají ratón was the principal source of lutein. In legumes, chocho perla (Lupinus mutabilis Sweet) showed the highest values for both total phenolic and flavonoid content, whilst frejol negro (Phaseolus vulgaris L.) and frejol canario (Vigna unguiculata (L.) Walp) showed the highest values for FRAP and DPPH assay, respectively. Between tubers, the jícama (Smallanthus sonchifolius (Poepp.) H. Rob.) had the majors values in terms of total phenolic, flavonoid content, and total antioxidant capacity. In terms of total antioxidant capacity, taxo fruits have the highest contribution in terms of total antioxidant capacity, whilst the dendogram shown the occurrence of five distinct groups in which taxo was located in the first largest group. Our data contributing towards gaining better knowledge about the Andean Ecuadorian diet and the composition of Andean food in order to estimate dietary intakes of health-promoting components.