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1.
Article | IMSEAR | ID: sea-217377

ABSTRACT

Background: Anaemia has significant impact on health of the fetus as well as that of mother. Increased need of iron during pregnancy especially after 2nd trimester makes iron supplementation mandatory. Ferrous ascorbate is known to exist intact inside the gastrointestinal tract due to the stable chelation of iron with ascorbate. This compound does not dissociate due to any of the food inhibitors. The aim is to study the effec-tiveness of Ferrous Ascorbate and Ferrous sulphate in terms of compliance and cost effectiveness of manage-ment of anaemia in pregnancy. Methodology: Study design: Quasi Experimental study, Study area: District Vidisha, Study participants: Preg-nant women of first trimester registered during the study period in the selected Anganwadis/ Gram Arogya Kendra (GAK), Sample size: 240 antenatal mothers. Results: Baseline mean haemoglobin was 11.31±1.05 gm/dl. The mean increase in Ferrous Sulphate was 0.55 gm/dl, and in Ferrous ascorbate was 1.27 gm/dl. Ferrous Sulphate was less compliant than Ferrous ascorbate, and has higher efficacy and lesser side effects. Only Rs. 10.2 additional cost per antenatal mothers for increase of ≥1gm% in Hb will be borne by government if Ferrous Sulphate is replaced by Ferrous Ascorbate. Conclusions: Study results show statistically significant difference in rise of haemoglobin amongst the ante-natal mothers consuming Ferrous ascorbate over Ferrous Sulphate

2.
Braz. arch. biol. technol ; 65: e22200702, 2022. tab, graf
Article in English | LILACS | ID: biblio-1364476

ABSTRACT

Abstract: Boron is one of the most important micronutrients for plants. Plants may suffer from deficiency or with boron toxicity. Boron plays a role in significant physiological and biochemical events in plants such as synthesis of the cell wall, membrane integrity, antioxidation, transport of photosynthesis products to other organs of the plant. The enzyme activities of ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR) and superoxide dismutase (SOD) in three different safflower cultivars (Balcı, Dinçer and Remzibey) subjected to different boric acid concentrations (0, 5, 10, 15 mM) were measured spectrophotometrically, and the changes in the expression levels of the genes that encode these enzymes were obtained by quantitative RT-qPCR. When both the spectrophotometric measurements and the mRNA values were evaluated together, both the activity and mRNA values of APX and GR enzymes were found to be the highest in the Dinçer cultivar among the varieties treated with 15 mM boric acid, while the lowest values of these enzymes were determined in the Remzibey cultivar. According to the RT-qPCR results, the lowest SOD and CAT values were determined in Remzibey. The Dinçer cultivar was found to have the highest antioxidant capacity (APX, GR) to cope with oxidative stress caused by boric acid application at high concentrations. The sensitive Remzibey cultivar was found to have the lowest antioxidant capacity to cope with such oxidative stress. Balcı was found to be closer to Dinçer than to Remzibey in terms of boron tolerance. As a result, the boron-sensitive cultivar had low antioxidant activity.


Subject(s)
Trace Elements/administration & dosage , Boron/administration & dosage , Crop Production , Carthamus tinctorius/metabolism , Antioxidants/metabolism , Trace Elements/toxicity , Boron/toxicity , Gene Expression/drug effects , Oxidative Stress/drug effects , Carthamus tinctorius/enzymology , Carthamus tinctorius/genetics
3.
Article in English | LILACS-Express | LILACS | ID: biblio-1385811

ABSTRACT

ABSTRACT: The objective of this in vitro study was to assess the effects of two antioxidants (sodium ascorbate [SA] and alpha-tocopherol [AT]) on the adhesive interface and dentin bond strength immediately after bleaching with 38 % hydrogen peroxide (38HP) in endodontically-treated teeth. Two stages of experimentation were carried out. Bovine incisors were allocated into four groups (n = 10/group for each experiment): NB, non-bleached restored crowns; 38HP, bleached and immediately restored crowns; 38HP-SA, bleached crowns and SA use; and 38HP-AT, bleached crowns and AT use. Hybrid layer length in dentin (μm) and bond strength (MPa) were assessed with confocal microscopy laser and micro-shear bond strength (μSBS) test, respectively. Failure mode was determined by stereomicroscope. Data analysis was performed with analysis of variance (ANOVA) and Kruskal-Wallis, Dunn, Tukey, and Fisher-exact tests (a = 0.05). Higher values of hybrid layer length were observed similarly in the NB and 38HP-SA groups. The highest μSBS mean values were observed in the NB group (18 .51 ? 1.33), whereas the SBS values for 38HP-AT (1.68 ? 0.32) were similar to the 38HP group (1.61 ? 0.51) (p > 0.05) and significantly lower than the 38HP-SA group (5.78 ? 0.71). Adhesive failures were predominant in the 38HP and 38HP-AT groups. Cohesive and mixed failures were mostly observed in the NB and 38HP-SA groups, respectively. In conclusion, AT has no immediate effect on the hybrid layer formation and μSBS of dentin. Although SA promotes an increase in hybrid layer formation, it was not reflected in the μSBS values.


RESUMEN: El objetivo de este estudio in vitro fue evaluar los efectos de dos antioxidantes (ascorbato de sodio [AS] y alfa-tocoferol [AT]) sobre la interfaz adhesiva y la fuerza de unión de la dentina inmediatamente después del blanqueamiento con peróxido de hidrógeno al 38 % (38HP) en endodoncia. -Dientes tratados. Se llevaron a cabo dos etapas de experimentación. Los incisivos bovinos se dividieron en cuatro grupos (n = 10 / grupo para cada experimento): NB, coronas restauradas no blanqueadas; 38HP, coronas blanqueadas y restauradas inmediatamente; 38HP- AS, coronas blanqueadas y uso SA; y 38HP-AT, coronas blanqueadas y uso de AT. La longitud de la capa híbrida en dentina (μm) y la fuerza de unión (MPa) se evaluaron con láser de microscopía confocal y la prueba de fuerza de unión por micro-cizallamiento (μSBS), respectivamente. El modo de falla se determinó mediante estereomicroscopio. El análisis de los datos se realizó con análisis de varianza (ANOVA) y pruebas de Kruskal-Wallis, Dunn, Tukey y Fisher (α = 0,05). De manera similar, se observaron valores más altos de longitud de capa híbrida en los grupos NB y 38HP-AS. Los valores medios más altos de μSBS se observaron en el grupo NB (18,51 ? 1,33), mientras que los valores de SBS para 38HP-AT (1,68 ? 0,32) fueron similares a los del grupo 38HP (1,61 ? 0,51) (p> 0,05) y significativamente más bajos que el grupo 38HP-AS (5,78 ? 0,71). Las fallas adhesivas fueron predominantes en los grupos de 38HP y 38HP-AT. Las fallas cohesivas y mixtas se observaron principalmente en los grupos NB y 38HP-AS, respectivamente. En conclusión, la AT no tiene un efecto inmediato sobre la formación de la capa híbrida y el μSBS de dentina. Aunque AS promueve un aumento en la formación de capas híbridas, no se refleja en los valores de μSBS.

4.
West China Journal of Stomatology ; (6): 453-457, 2021.
Article in English | WPRIM | ID: wpr-887758

ABSTRACT

OBJECTIVES@#This work aimed to evaluate the ability of two kinds of antioxidants, namely, grape-seed extract and sodium ascorbate, in restoring bond strength at the resin-enamel interface after bleaching.@*METHODS@#Ten groups of samples with 15 teeth per group were prepared for shear-bond-strength test at the resin-enamel interface after bleaching. The groups were as follows: control; no antioxidant; 2.5%, 5%, 10%, or 15% grape-seed extract; and 2.5%, 5%, 10%, or 15% sodium ascorbate. The peak values of shear bond strength when resin was debonded from teeth and the failure modes under a microscope were recorded. Ten other groups of teeth with two teeth per group were prepared and treated in a similar approach before resin bonding. The samples were cut vertically to the bonding interface. The structures of the bonding interface were compared by scanning electron microscopy.@*RESULTS@#No statistically significant difference in shear bond strength was found among the no-antioxidant, 2.5% grape-seed extract, and 2.5%, 5%, or 10% sodium ascorbate groups (@*CONCLUSIONS@#Immediately after bleaching, the bond strength of dental enamel significantly decreased. Bond strength can be restored by 5% grape-seed extract or 15% sodium ascorbate in 5 min.


Subject(s)
Humans , Antioxidants , Composite Resins , Dental Bonding , Dental Cements , Dental Enamel , Shear Strength , Tooth Bleaching
5.
Dental press j. orthod. (Impr.) ; 25(5): 38-43, Sept.-Oct. 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1133687

ABSTRACT

ABSTRACT Objective: To evaluate a protocol for bonding metallic brackets after bleaching with hydrogen peroxide (HP). Methods: 60 extracted maxillary premolar were randomly divided into an unbleached control group and two groups bleached with a solution of 35% hydrogen peroxide prior to bonding. The teeth in one of the treated groups were bonded immediately after bleaching; while the other group was treated with 10% sodium ascorbate immediately after bleaching and before bonding. The teeth in all groups were stored in an artificial saliva solution for 7 days after bonding. The shear bond strength data was measured in megapascals (MPa) and the fail attempts were verified. The significance level was established at p< 0.05. Results: The unbleached group, in which brackets were bonded to untreated enamel, had the highest bond strength values (11.0 ± 5.7MPa) in comparison to the bleached group (7.14 ± 40MPa), in which brackets were bonded to recently bleached enamel. Slightly improved bond strength was observed in the antioxidant group (8.13 ± 5.4MPa), in which the teeth were bleached and then the antioxidant was applied to the teeth before bonding. Unbleached and bleached groups showed statistically significant difference for shear bond strength (p=0.03) and load strength (p=0.03); no significant differences were noted between unbleached and antioxidant groups (p=0.52). Conclusion: The antioxidant treatment applied immediately after bleaching was effective in reversing the reduction in shear bond strength of brackets after tooth bleaching.


RESUMO Objetivo: Avaliar um protocolo para colagem de braquetes metálicos após clareamento com peróxido de hidrogênio (PH). Método: Sessenta pré-molares superiores extraídos foram aleatoriamente divididos em um Grupo Controle (sem clareamento) e dois grupos que receberam clareamento, antes da colagem, com solução de peróxido de hidrogênio a 35%. Em um dos grupos tratados (Grupo Clareamento), os braquetes foram colados imediatamente após o clareamento, enquanto o outro (Grupo Antioxidante) foi tratado com ascorbato de sódio a 10%, imediatamente após o clareamento e antes da colagem. Os dentes, em todos os grupos, foram armazenados em saliva artificial por 7 dias após a colagem. As informações relativas à resistência da colagem foram registradas em megapascals (MPa) e as tentativas fracassadas foram verificadas. O nível de significância foi estabelecido em p < 0,05. Resultados: O Grupo Controle, no qual os braquetes foram colados ao esmalte não clareado, apresentou os valores mais altos de força de adesão (11,0 ± 5,7 MPa), em comparação ao Grupo Clareamento (7,14 ± 40 MPa), no qual os braquetes foram colados ao esmalte recém-clareado. Uma suave melhora na força de adesão foi observada no Grupo Antioxidante (8,13 ± 5,4 MPa), no qual, após os dentes serem clareados, foi aplicado antioxidante aos dentes, antes da colagem. Os Grupos Controle e Clareamento apresentaram uma diferença estatisticamente significativa para a resistência da colagem (p =0,03) e a resistência à carga (p= 0,03); porém, nenhuma diferença significativa foi notada entre os Grupos Controle e Antioxidante (p =0,52). Conclusão: O tratamento antioxidante aplicado imediatamente após o clareamento foi efetivo em reverter a diminuição da resistência da colagem dos braquetes após o clareamento dentário.


Subject(s)
Tooth Bleaching , Dental Bonding , Orthodontic Brackets , Dental Enamel , Shear Strength
6.
Article | IMSEAR | ID: sea-208034

ABSTRACT

Background: Iron deficiency anemia is the most common form of anemia and nutritional disorder worldwide. Oral iron therapy and blood transfusion has many drawbacks like noncompliance and risk of transmittable infections and transfusion reaction. The modern alternative therapy is treatment with intravenous iron. Present study compares the efficacy, safety and tolerability between intravenous iron sucrose and oral iron in iron deficiency anemia during 20-36 weeks of pregnancy.Methods: It was a randomized controlled study between December 2017 to September 2019. 200 patients attending antenatal OPD in Al Ameen Medical College, with haemoglobin levels between 7-9.9 gm/dl and serum ferritin of <15 ng/ml were enrolled. In intravenous group, 200 mg iron sucrose in 100ml normal saline was infused alternate day till the required dose was met. The oral group received 200 mg of oral iron ascorbate along with folic acid 1.5 mg per day for 6 weeks.  Treatment efficacy was assessed by Hb and serum ferritin after 3 and 6 weeks.Results: Out of 200 patients, an increase in Hb was observed in both groups, rising from 9.7 g/dl to 10.3 g/dl and 10.9 g/dl after 3 weeks and 6 weeks respectively in oral group and from 8.6 g/dl to 9.8 g/dl and 10.8 g/dl after 3 weeks and 6 weeks respectively in intravenous group. Similar results were seen in ferritin levels. Rise in Hb and ferritin levels were greater in intravenous group than in oral group.Conclusions: Intravenous iron sucrose appears to be a better treatment option in comparison with oral iron, without serious side effects, better compliance and improved efficacy in correction of anaemia of pregnancy.

7.
Article | IMSEAR | ID: sea-203723

ABSTRACT

The aim of the study was to investigate the effect of a new anti-stress drug on protein and lipid metabolism in thecultivation and fattening of pigs. The experiment was carried out on 5 groups of pigs of Irish Landrace breed (4experimental and 1 control) with 10 heads in each in the period from 60 to 210 days of age. Animals of 1, 2, 3and 4 experimental groups daily during the entire period of rearing and fattening received lithium ascorbate inthe form of powder at a dose of 10, 5, 2 and 0.5 mg/kg of live weight, respectively. Weighing was carried outbefore the introduction of the drug, for the 4th month and before slaughter. Before setting the animals in theexperiment and on the 180th day of the experiment, blood samples were taken. Triacylglycerols, total protein andglobulins, and fractions of lipoproteins were determined in blood plasma. Acting on protein and lipid metabolism,lithium ascorbate activates the functions associated with the participation of α-, β - globulins in the transport oflipids, as well as in the performance of γ-globulins protective functions. Lithium ascorbate has a positive effecton lipid-cholesterol metabolism and, as a result, contributes to the increase in live weight and quality of meat.With the introduction of feed lithium ascorbate from the 60th day prior to slaughter at a dosage of 10, 5 and 2mg/kg of body weight, lithium ascorbate exhibits a pronounced adaptogenic and stress-protection properties,prevents the accumulation of lipoproteins of low and very low density and activates the production of high-densitylipoproteins. And in the control animals, it is is observed in the reverse reaction. The use of lithium ascorbateaffects protein synthesis. Given that γ-and β-globulins serve as raw materials for the production ofimmunoglobulins, it can be noted that the animals treated with lithium ascorbate had the best opportunities forhumoral specific protection for 180 days of experience, which contributes to the increase of nonspecific immunityand resistance. The revealed effects of lithium ascorbate indicate the prospects for the development of neweffective ways to increase stress resistance, nonspecific resistance and productivity of animals using drugs basedon organic lithium salts.

8.
Article | IMSEAR | ID: sea-200464

ABSTRACT

Background: Anaemia is a global health concern, associated with increased maternal and perinatal mortality, preterm delivery, low birth weight, extreme fatigue and impaired immune system; and controlled by oral haematinics; with a rise in haemoglobin concentration. The objective was to examine the various aspects of pharmacoepidemiology and pharmacohaemovigilance of oral haematinics, among the anaemic women population, in rural India.Methods: This was a multi-centre, retrospective, observational and analytical study of the hospital medical records of 250 anaemic patients, who were allocated into group A of 125 patients within 15-21 years and group B of 125 patients within 22-35 years. The patients were prescribed oral haematinics, containing 60 mg of elemental iron, thrice daily, with meals. The various aspects of pharmacoepidemiology and pharmacohaemovigilance of ferrous ascorbate, ferrous sulphate, ferrous fumarate and ferric ammonium citrate, including patients’ demographic characteristics, anaemic symptoms assessment, prescription patterns, and safety assessment, on 1st, 2nd, 3rd months and follow-up visits, were recorded and thoroughly analysed..Results: In groups A and B, the demographic characteristics of the patients were comparable; ferrous ascorbate was the most commonly prescribed oral haematinic, followed by ferrous sulphate, ferrous fumarate and ferric ammonium citrate, which controlled mild to moderate iron deficiency anaemia, with a gradual significant rise in haemoglobin concentration, in the successive 3 months; and adverse effects were observed to be statistically non-significant in either group.Conclusions: The different aspects of pharmacoepidemiology and pharmacohaemovigilance in the study established that the oral haematinics were reasonably beneficial and safe among the anaemic women population, in rural India.

9.
Article | IMSEAR | ID: sea-207013

ABSTRACT

Background: The post-partum period is challenging enough for most new mothers. Recovering from birth, learning to parent, and taking care of her child requires lot of energy. Having anemia in postpartum period can make this process much more difficult. According to WHO, in India incidence of anemia in postnatal mother is around 58% and according to ICMR prevalence of anemia in Tamil Nadu population 76% during pregnancy. The objective of this study was to compare the efficacy of intravenous iron supplementation with Iron sucrose to the oral supplementation with ferrous ascorbate in management of patient with post-partum anemia. To study the safety and side effects of these two preparations.Methods: This was a prospective study conducted on 100 post-partum anemic women in KG Hospital  in Coimbatore, October 2012 to November 2013 with hemoglobin less than 10g/dl but more than 6g/dl within 24-48 hours of delivery ,after satisfying inclusion and exclusion criteria were included in the study.Results: Mean hemoglobin of oral group was 8.49±0.75 and mean hemoglobin of IV group was 8.43±0.76; 24 hours after delivery. After treatment, that is after 4 weeks mean hemoglobin of oral group was 10.38±0.79 and mean hemoglobin of IV group was 11.20±0.71.on comparing both groups, the increase in hemoglobin in the IV groups was significant. Reticulocyte count and other parameters increased significantly after four wks of starting therapy in IV group compare to the oral group. No major side effects or anaphylactic reactions were noted during study period.Conclusions: Intravenous iron sucrose complex is safe, convenient and effective in postpartum anemic women as compared with the oral ferrous ascorbate. Intravenous iron sucrose have shorter treatment periods, increased likelihood of compliance, a lack of gastrointestinal side effects, and rapid replenishment of iron stores, making them superior to oral ferrous ascorbate.

10.
Article | IMSEAR | ID: sea-206578

ABSTRACT

Background: Anemia due to Iron deficiency is the commonest malnutrition disorder seen throughout the world and in India. It is also responsible for increased incidence of premature births, low birth weight babies and high perinatal mortality. Hence, the present study undertaken to assess efficacy and safety of injectable iron sucrose with oral ferrous ascorbate.Methods: 100 pregnant women, between gestational age 14 and 28 weeks were divided randomly into two groups i.e. group A consists of oral iron, a total of 200 mg of elemental iron per day, two 100mg iron tablets per day and group B consists of iron sucrose at the rate of 200mg on alternate OPD day. Informed consent was taken from each patient.Results: The percentage rise in hemoglobin at fourth and eighth weeks of treatment was statistically significant when compared to the baseline. Statistically significant rise in hemoglobin, PCV and ferritin levels were found at fourth and eighth weeks in IV group when compared to oral group.Conclusions: This study concluded that intravenous iron sucrose is safe and highly efficacious for the treatment of anemia in pregnancy. It restores iron stores more promptly. Iron sucrose therapy is more effective in achieving the optimum results, an increase in hemoglobin concentration, PCV levels and an increase in ferritin levels also. Therefore, it is a suitable alternative to oral iron with minimal side effects in those patients who cannot tolerate oral iron therapy.

11.
Article | IMSEAR | ID: sea-192193

ABSTRACT

Context: The use of antioxidants immediately after bleaching showed increased bond strength. Aims: This study aimed to compare the effects of natural antioxidants on the shear bond strength of composite resin to bleached enamel. Materials and Methods: Fifty extracted single-rooted upper incisors were decoronated by sectioning the roots 2 mm below the cementoenamel junction, and then, crowns were embedded in autopolymerizing acrylic resin block (3.0 cm × 3.0 cm × 3.0 cm) with the labial surface exposed. They were randomly divided into five groups, depending on the type of antioxidant used (n = 10): (i) Group 1: control (no bleaching), (ii) Group 2: bleaching only, (iii) Group 3: bleaching + 10% sodium ascorbate (antioxidant), (iv) Group 4: bleaching + green tea, and (v) Group 5: bleaching + white tea. Labial surfaces of 40 teeth were bleached with 38% hydrogen peroxide for 20 min following manufacturer's instructions. After that, the experimental groups (Groups 3, 4, and 5) were treated with respective antioxidant solutions before composite restorations were done using a cylindrical plastic mold (3 mm × 5 mm). Shear bond strength of the specimens was tested under universal testing machine. Statistical Analysis: Data were analyzed with ANOVA and Tukey's post hoc test. Results: There were statistically significant differences between shear bond strength of control groups (Groups 1 and 2) and experimental groups (P < 0.05), but no significant difference in bond strength was observed among the antioxidants used. Conclusion: Application of antioxidants immediately after bleaching showed increased bond strength. Green tea and white tea extract can be used as alternative antioxidants in improving the bond strength of enamel.

12.
Braz. arch. biol. technol ; 62: e19180251, 2019. tab, graf
Article in English | LILACS | ID: biblio-1039118

ABSTRACT

Abstract Higher levels of reactive species of oxygen are harmful to plant tissues. This study evaluated the action of different doses of thymol on soybean seed germination, biometric analysis and enzymatic parameters; both involved in germination process. High doses of thymol affected the plantlet growth, but not hampered the germination.


Subject(s)
Glycine max , Ascorbate Peroxidases , Superoxide Dismutase , Catalase , Germination
13.
Arq. Inst. Biol ; 86: e0312017, 2019. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1000033

ABSTRACT

The objective of this research was to evaluate the response of wheat plants to the application of possible elicitor compounds against Bipolaris sorokiniana pathogen. This response was measured through the quantification of antioxidant enzymes, malondialdehyde and flavonoids, evaluation of the severity of brown spot disease and productivity in wheat, greenhouse and field crops. The treatments consisted of suspensions of endophytic fungi Aspergillus japonicus and Trichoderma tomentosum, salicylic acid, acibenzolar-S-methyl and fungicide. In the field trials, in 2015 and 2016, the development of the disease was lower and productivity was higher in all treatments, with emphasis on the fungicide. However, endophytic fungi suspensions demonstrated potential as growth promoters, disease severity reducers and protective antioxidant response activators, as they promoted significant increase in superoxide dismutase, catalase, glutathione and flavonoid enzymes.(AU)


O objetivo desta pesquisa foi avaliar a resposta de plantas de trigo diante da aplicação de possíveis compostos elicitores perante o patógeno Bipolaris sorokiniana. Tal resposta foi examinada por meio da quantificação de enzimas antioxidantes, malondialdeído e flavonoides, da análise da severidade da doença mancha marrom e da produtividade na cultura do trigo, em casa de vegetação e em campo. Os tratamentos consistiram em suspensões de fungos endofíticos Aspergillus japonicus e Trichoderma tomentosum, ácido salicílico, acibenzolar-S-metil e fungicida. Nos ensaios em campo, em 2015 e 2016, o desenvolvimento da doença foi menor e a produtividade foi superior em todos os tratamentos, com destaque para o fungicida. No entanto, as suspensões de fungos endofíticos demonstraram potencial como promotores de crescimento, redutores da severidade da doença e ativadores de resposta antioxidante protetora, pois promoveram o aumento significativo das enzimas superóxido dismutase e catalase, das glutationas e flavonoides.(AU)


Subject(s)
Triticum , Noxae , Aspergillus , Trichoderma , Flavonoids , Catalase , Glutathione
14.
Odovtos (En línea) ; 20(3): 71-79, Sep.-Dec. 2018. tab
Article in Spanish | LILACS, BBO | ID: biblio-1091461

ABSTRACT

RESUMEN El objetivo del presente estudio fue evaluar los efectos de la aplicación de un antioxidante sobre las fuerzas de unión (SBS) de brackets de ortodoncia posterior al blanqueamiento con peróxido de hidrógeno (HP). Metodología: Cincuenta premolares recién extraídos se dividieron aleatoriamente en tres grupos. El Grupo 1 se trató con 40% de HP (n=20), el grupo 2 con 40% de HP y se activó con láser de Nd: YAG (n=20) y un grupo de control (Grupo 3) no recibió tratamiento (n=10). Después del blanqueamiento, los Grupos 1 y 2 se dividieron en dos subgrupos (Grupo 1a, Grupo 1b, Grupo 2a y Grupo 2b). Las muestras en los subgrupos 1a y 2a (n=10) no recibieron ninguna aplicación del antioxidante. Se aplicó una solución de ascorbato de sodio al 10% a las muestras en los Grupos 1b y 2b (n=10). Luego, los brackets se adherieron a las superficies de esmalte de todos los grupos experimentales. Las muestras se sometieron a pruebas de SBS y los datos analizados estadisticamente. Resultados: La fuerza de unión de los grupos 1 y 2 fue significativamente más baja que el grupo de control (p <0.001); sin embargo, no se observaron diferencias estadísticamente significativas en SBS entre los grupos 1 y 2 (p>0.001). Las muestras tratadas con antioxidantes de los grupos 1b y 2b fueron significativamente mayores que las de los grupos 1a y 2a (p <0,001). Conclusion: La aplicación de 40% HP tuvo un efecto negativo en la resistencia de unión de los brackets. El uso de antioxidante durante 15 minutos mejoró significativamente la SBS.


ABSTRACT Purpose: The purpose of this study was to evaluate the effects of the application of antioxidant on the shear bond strengths (SBS) of orthodontic brackets bonded to human enamel after extra-coronal bleaching with hydrogen peroxide (HP). Materials and methods: Fifty freshly extracted premolars were randomly divided into three groups. One group (Group 1) was bleached with 40% HP (n=20), another group (Group 2) was bleached with 40% HP and activated with an Nd: YAG laser (n=20), and a control group (Group 3) received no treatment (n=10). After the bleaching procedure, Groups 1 and 2 were further divided into two subgroups (Group 1a, Group 1b, Group 2a, and Group 2b). Specimens in Groups 1a and 2a (n=10) received no antioxidant application. A 10% sodium ascorbate solution was applied to specimens in Groups 1b and 2b (n=10). The brackets were then bonded with light-cure adhesive paste to the enamel surfaces of all experimental groups. Specimens were subjected to SBS tests for debonding. Results: The SBS of brackets bonded in Groups 1 and 2 were significantly lower than those of brackets bonded to the control group (p<0.001); however, no statistically significant differences in SBS were noted in Groups 1 and 2 (p>0.001). The antioxidant-treated SBS of brackets in Groups 1b and 2b were significantly higher than those of Groups 1a and 2a (p<0.001). Conclusions: The application of 40% HP had a negative effect on the bond strength. The use of antioxidant for 15 min resulted in the reversal of failed bond strength.


Subject(s)
Tooth Bleaching/methods , Orthodontic Brackets , Shear Strength/drug effects , Hydrogen Peroxide/adverse effects , Laser Therapy
15.
Article | IMSEAR | ID: sea-192134

ABSTRACT

Whitening of teeth is a popular choice among dental clinicians and patients. However, the changes in enamel structure and composition induced by the bleaching agents cause a decrease in the shear bond strength of brackets leading to premature bracket debonding. Among several methods to overcome this, the most common is delaying bonding by 2–4 weeks. This waiting period can be eliminated by applying an antioxidant (sodium ascorbate) which causes a reversal in the reduction of bond strength. Aim: This study aims to compare the efficacy of a naturally occurring antioxidant (gooseberry) and sodium ascorbate in normalizing the bond strength of enamel to prebleached levels. Materials and Methods: Seventy-two extracted premolars were divided into 4 equal groups; 1st group – control group – unbleached teeth, bonded directly, 2nd group – bleached with 16% carbamide peroxide (8 h for 1 week), then bonded. 3rd and 4th group – similarly bleached, followed by application of 10% sodium ascorbate and gooseberry extract (3 h respectively), then bonded. Bond strength was checked using Instron Universal Testing Machine. Results: The bond strength of the control group was the highest and that of the carbamide group was drastically reduced. Considerable increase in the bond strength was seen after treatment with sodium ascorbate with negligible difference between sodium ascorbate and control group (P > 0.05). Conclusion: Treatment with gooseberry extract did improve the bond strength but was not as effective as sodium ascorbate postbleaching.

16.
The Korean Journal of Parasitology ; : 1-9, 2018.
Article in English | WPRIM | ID: wpr-742229

ABSTRACT

Giardia lamblia, an anaerobic, amitochondriate protozoan parasite causes parasitic infection giardiasis in children and young adults. It produces pyruvate, a major metabolic product for its fermentative metabolism. The current study was undertaken to explore the effects of pyruvate as a physiological antioxidant during oxidative stress in Giardia by cysteine-ascorbate deprivation and further investigation upon the hypothesis that oxidative stress due to metabolism was the reason behind the cytotoxicity. We have estimated intracellular reactive oxygen species generation due to cysteine-ascorbate deprivation in Giardia. In the present study, we have examined the effects of extracellular addition of pyruvate, during oxidative stress generated from cysteine-ascorbate deprivation in culture media on DNA damage in Giardia. The intracellular pyruvate concentrations at several time points were measured in the trophozoites during stress. Trophozoites viability under cysteine-ascorbate deprived (CAD) medium in presence and absence of extracellular pyruvate has also been measured. The exogenous addition of a physiologically relevant concentration of pyruvate to trophozoites suspension was shown to attenuate the rate of ROS generation. We have demonstrated that Giardia protects itself from destructive consequences of ROS by maintaining the intracellular pyruvate concentration. Pyruvate recovers Giardia trophozoites from oxidative stress by decreasing the number of DNA breaks that might favor DNA repair.


Subject(s)
Child , Humans , Young Adult , Culture Media , DNA Breaks , DNA Damage , DNA Repair , Giardia lamblia , Giardia , Giardiasis , Metabolism , Oxidative Stress , Parasites , Pyruvic Acid , Reactive Oxygen Species , Trophozoites
17.
Braz. arch. biol. technol ; 61: e18160758, 2018. tab, graf
Article in English | LILACS | ID: biblio-974053

ABSTRACT

ABSTRACT Present study was carried out to investigate the effects of different Zn concentrations on growth and some antioxidant responses in Chenopodium murale L. The seeds were sown on the pots. 45-day plants were transferred to hydroponic solution containing 0.2 (control), 150, 300 and 600 µM Zn. The plants were harvested at 6 days after applying Zn treatments and some parameters were evaluated including plant length, fresh weight, photosynthetic pigments, malondialdehyde (MDA), ascorbate, proline and enzymatic antioxidants such as catalase (CAT), guaiacol peroxidase (GPX) and superoxide dismutase (SOD). Zn concentration showed a considerable increase in the shoot and root as the concentration of Zn increased in the medium, meanwhile the roots were characterized by higher Zn accumulation. At 150 µM Zn, the length and fresh weight did not show important changes compared to the control, but these parameters decreased at 300 and 600 µM Zn. With increasing Zn doses, the content of total chlorophyll declined, and also the content of carotenoids elevated. Excess Zn led to an increase in lipid peroxidation, free proline and ascorbate pool. Moreover, elevated Zn levels enhanced the activities of CAT, GPX and SOD. C. murale probably tolerates Zn concentrations up to 150 µM using the production of carotenoid, proline and ascorbate as well as enhanced activity of enzymatic antioxidants. Higher Zn treatments seem to be toxic due to a severe decline in growth.

18.
Mem. Inst. Oswaldo Cruz ; 113(12): e180377, 2018. graf
Article in English | LILACS | ID: biblio-1040587

ABSTRACT

Ascorbate peroxidase (APX) is a redox enzyme of the trypanothione pathway that converts hydrogen peroxide (H2O2) into water molecules. In the present study, the APX gene was overexpressed in Leishmania braziliensis to investigate its contribution to the trivalent antimony (SbIII)-resistance phenotype. Western blot results demonstrated that APX-overexpressing parasites had higher APX protein levels in comparison with the wild-type line (LbWTS). APX-overexpressing clones showed an 8-fold increase in the antimony-resistance index over the parental line. In addition, our results indicated that these clones were approximately 1.8-fold more tolerant to H2O2 than the LbWTS line, suggesting that the APX enzyme plays an important role in the defence against oxidative stress. Susceptibility tests revealed that APX-overexpressing L. braziliensis lines were more resistant to isoniazid, an antibacterial agent that interacts with APX. Interestingly, this compound enhanced the anti-leishmanial SbIII effect, indicating that this combination represents a good strategy for leishmaniasis chemotherapy. Our data demonstrate that APX enzyme is involved in the development of L. braziliensis antimony-resistance phenotype and may be an attractive therapeutic target in the design of new strategies for leishmaniasis treatment.


Subject(s)
Leishmania braziliensis/drug effects , Leishmania braziliensis/enzymology , Ascorbate Peroxidases/metabolism , Antimony/pharmacology , Antiprotozoal Agents/pharmacology , Phenotype , Drug Resistance , Gene Expression Regulation, Enzymologic , Protozoan Proteins/metabolism , Blotting, Western , Oxidative Stress , Parasitic Sensitivity Tests
19.
The Korean Journal of Physiology and Pharmacology ; : 35-42, 2018.
Article in English | WPRIM | ID: wpr-727940

ABSTRACT

Ascorbic acid is one of the most well-known nutritional supplement and antioxidant found in fruits and vegetables. Calcium ascorbate has been developed to mitigate the gastric irritation caused by the acidity of ascorbic acid. The aim of this study was to compare calcium ascorbate and ascorbic acid, focusing on their antioxidant activity and effects on gastric juice pH, total acid output, and pepsin secretion in an in vivo rat model, as well as pharmacokinetic parameters. Calcium ascorbate and ascorbic acid had similar antioxidant activity. However, the gastric fluid pH was increased by calcium ascorbate, whereas total acid output was increased by ascorbic acid. In the rat pylorus ligation-induced ulcer model, calcium ascorbate increased the gastric fluid pH without changing the total acid output. Administration of calcium ascorbate to rats given a single oral dose of 100 mg/kg as ascorbic acid resulted in higher plasma concentrations than that from ascorbic acid alone. The area under the curve (AUC) values of calcium ascorbate were 1.5-fold higher than those of ascorbic acid, and the C(max) value of calcium ascorbate (91.0 ng/ml) was higher than that of ascorbic acid (74.8 ng/ml). However, their T(max) values were similar. Thus, although calcium ascorbate showed equivalent antioxidant activity to ascorbic acid, it could attenuate the gastric high acidity caused by ascorbic acid, making it suitable for consideration of use to improve the side effects of ascorbic acid. Furthermore, calcium ascorbate could be an appropriate antioxidant substrate, with increased oral bioavailability, for patients with gastrointestinal disorders.


Subject(s)
Animals , Humans , Rats , Ascorbic Acid , Biological Availability , Calcium , Fruit , Gastric Juice , Hydrogen-Ion Concentration , In Vitro Techniques , Models, Animal , Pepsin A , Plasma , Pylorus , Ulcer , Vegetables
20.
Braz. arch. biol. technol ; 59: e16160389, 2016. tab, graf
Article in English | LILACS | ID: biblio-951408

ABSTRACT

ABSTRACT An efficient in vitro regeneration protocol for medicinally important herb Swertia chirayita was developed and the genetic fidelity was assessed using RAPD and ISSR markers. The best shoot regeneration was observed on MS basal supplemented with 1.0 mg/L Benzyl amino purine (BAP) in combination with Indole-3-acetic acid (IAA) (0.5 mg/L) that resulted in the increase by multiplication rate (7.65) with an average of 33.33 numbers of shoots and average shoot length of 2.70 cm. It was further enhanced by the addition of adenine sulfate (0.007%) that resulted in an average of 42 shoots per clum with 4.13 cm of average shoot length and the increase in multiplication fold to 9.75 that further resulted in the reduced use of other cytokinins and auxins. The rooting was nearly 100 % on 1/4 MS augmented with 1.0 mg/L Indole butyric acid with maximum average root length of 5.1cm. Plantlets were successfully acclimatized with 85-90 % survival rate. Ascorbate peroxidase activity increased with the maximum activity during the shoot multiplication. Clonal fidelity has been checked by two marker systems ISSR and RAPD and regenerated plants showed high clonal fidelity.

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