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1.
An. bras. dermatol ; 94(5): 561-566, Sept.-Oct. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1054858

RESUMO

Abstract Background Rubeosis faciei diabeticorum is a persistent facial erythema in patients with diabetes mellitus. The actual pathogenesis has not been studied. However, it is speculated to be a cutaneous diabetic microangiopathy. Objective Examine the correlation between the severity of facial erythema and the possible causes of microvascular diabetic complications, namely oxidative stress, hyperglycemia, and cutaneous accumulation of advanced glycation end-products . Methods Patients diagnosed with Type 2 diabetes mellitus (n = 32) were enrolled in the study. The facial erythema index was measured using the Mexameter MX18; cutaneous accumulation of advanced glycation end-products was estimated by measuring skin auto fluorescence with the AGE Reader (DiagnOptics Technologies B.V. - Groningen, Netherlands). Glycated haemoglobin, total antioxidant status, and malondialdehyde were measured in blood by TBARS assay. The correlation between the selected variables was assessed by Spearman's rank test; p ≤ 0.05 was considered statistically significant. Results There was a statistically significant correlation between total antioxidant status and the facial erythema index (ρ = 0.398, p = 0.024). Malondialdehyde, skin autofluorescence, glycated haemoglobin, body mass index, duration of diabetes, and age did not demonstrate statistically significant correlation with the facial erythema index. Study limitations This is an observational study. Elevation of total antioxidant status could have been caused by several factors that might have also influenced the development of rubeosis faciei, including hyperbilirubinemia and hyperuricemia. Conclusions The results contradicted expectations. Total antioxidant status correlated positively with facial erythema index; however, there was no correlation with oxidative stress and skin autofluorescence. Further investigations should be conducted to reveal the cause of total antioxidant status elevation in patients with rubeosis faciei.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Estresse Oxidativo , Angiopatias Diabéticas/metabolismo , Eritema/metabolismo , Dermatoses Faciais/metabolismo , Valores de Referência , Espectrofotometria , Hemoglobina A Glicada/análise , Índice de Massa Corporal , Estatísticas não Paramétricas , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Angiopatias Diabéticas/complicações , Eritema/etiologia , Dermatoses Faciais/etiologia , Fluorescência , Malondialdeído/sangue , Antioxidantes/análise
2.
Clin. biomed. res ; 39(3): 221-224, 2019.
Artigo em Português | LILACS | ID: biblio-1053046

RESUMO

Introdução: A comida tem um papel proeminente na obtenção do iodo e uma das melhores estratégias é a iodização do sal. No Brasil, a Anvisa reduziu as doses de iodo no sal de cozinha desde 2014. Portanto, é importante avaliar a concentração urinária de iodo (CIU) em nossa população. Com base no exposto, propõe-se avaliar a CIU das gestantes, associando-a à frequência de bócio materno, aborto e peso neonatal. Métodos: Trata-se de um estudo observacional com um corte transversal composto por 37 pacientes atendidos no Serviço de Obstetrícia da Faculdade de Medicina de Barbacena e uma clínica particular em Juiz de Fora. A CIU foi verificada em 24 horas de urina. Resultados: A média de CIU foi de 213,6 µg/l de urina, com dose mínima de 29 µg/l e máxima de 437 µg/l. A glândula tireoide foi avaliada durante o exame clínico prénatal (palpação da glândula) e em 24 pacientes (38,1%) foi considerada normal. A palpação da glândula tireoide foi associada à CIU. Houve maior iodúria em gestantes com glândula não palpável (p = 0,004; T = 14,13). Não houve associação entre a CIU e história de aborto ou peso fetal ao nascimento (p > 0,05). Conclusões: Apesar de ser uma amostra pequena da população, identificamos pacientes expostas ao déficit. No entanto, a CIU não parece estar associada ao peso do recém-nascido ou a abortos, mas à dosagem de TSH e ao tamanho da glândula tireoide. Assim, a palpação da glândula tireoide poderia ser usada como uma medida indireta do CIU. (AU)


Introduction: Food has a prominent role in providing iodine and one of the best strategies is salt iodization. The Brazilian Health Regulatory Agency has reduced iodine content in table salt since 2014. Therefore, there is a need for evaluating urinary iodine concentration in our population, especially after the modified recommendations. Based on the above, we sought to assess urinary iodine concentration in pregnant women, associating it with frequency of maternal goiter, abortion and neonatal weight. Methods: This observational, cross-sectional study included 37 patients seen at the Obstetrics Service of Barbacena Medical School and a private clinic in Juiz de Fora, both in the state of Minas Gerais, Brazil. Iodine concentration was determined in 24- hour urine through chromatography. Results: The mean 24-hour urine iodine was 213.6 µg/l, with minimum and maximum measures of 29 µg/l and 437 µg/l, respectively. The thyroid gland was assessed by prenatal clinical examination (palpation of the gland). In 24 patients (38.1%) it was considered normal. Palpation of the thyroid gland was associated with 24-hour urine iodine concentration, although a higher iodine concentration was identified in pregnant women with non-palpable gland (p = 0.004; T = 14.13). There was no association between 24-hour urine iodine concentration and history of abortion or birth weight (p > 0.05). Conclusions: This study, although based on a small sample of the population, was important to identify that even in areas where iodine is considered sufficient there may be patients exposed to iodine deficit. However, urinary iodine concentration does not appear to be associated with birth weight or abortion frequency but is associated with thyroid-stimulating hormone (TSH) level and thyroid gland size, suggesting that clinical evaluation of the thyroid gland is an important element for predicting urinary iodine concentration. Thus, palpation of the thyroid gland could be used as an indirect measure of urinary iodine concentration. (AU)


Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Adulto , Complicações na Gravidez/epidemiologia , Peso ao Nascer , Aborto Espontâneo/epidemiologia , Bócio/epidemiologia , Iodo/deficiência , Iodo/urina , Palpação , Complicações na Gravidez/urina , Cuidado Pré-Natal , Espectrofotometria , Estudos Transversais
3.
São Paulo; s.n; s.n; 2019. 60 p. graf, tab.
Tese em Português | LILACS | ID: biblio-1023080

RESUMO

A sobrecarga de ferro é uma condição prejudicial para os pacientes, que apresentam uma diminuição significativa na qualidade de vida. Os fármacos quelantes são moléculas que têm capacidade de uso clínico para atuar como atenuadores da sobrecarga de metais. Neste trabalho apresentamos uma análise de sideróforos do tipo hidroxamato e quinona, com o objetivo de ampliar a gama de terapia de sobrecarga de ferro. Para cada composto foi realizado um ensaio competitivo com a sonda calce- ína para verificar a capacidade de ligação do ferro, e um ensaio antioxidante baseado na supressão da oxidação dependente de ferro da dihidrorrodamina (DHR) sob ascorbato. Foi observado que o hidroxamato cíclico piridoxatina apresentou capacidade de sequestrar ferro de substratos de alta afinidade, tanto em meio tamponado quanto em meio intracelular. Em ambas as situações também se mostrou um antioxidante eficiente. Entretanto, parece ser o mais tóxico do grupo dos hidroxamatos (que ainda continha o hidroxamato linear desferricoprogênio e o aromático desferriastercromo). Outros compostos naturais também foram estudados como possíveis candidatos a fármacos para sobrecarga de ferro. Complexos de ferro foram caracterizados por espectrofotometria para avaliar a estequiometria possível, considerando os sítios de ligação para cada composto. Ensaios de fluorescência revelaram que entre os quatro compostos em estudo (ácido clorogênico, lapachol, hemateína e hematoxilina), o complexo entre ferro e hemateína apresenta maior estabilidade relativa do que outros


Iron overload is a harmful condition for patients, who have a significant decrease in life quality. Chelating drugs are molecules that have the capacity for clinical use to act as attenuators of metal overload. In this work we present an analysis of hydroxamate and quinone-type siderophores, intending to broaden the range of iron overload therapy. For each compound it was conducted a competitive assay with the fluorescent probe calcein to verify the iron binding ability, and an antioxidant assay based on suppression of the iron-dependent oxidation of dihydrorhodamine (DHR) under ascorbate. It was observed that cyclic hydroxamate pyridoxatin displayed good ability to scavenge iron from high affinity substrates both in buffer and in intracellular medium. It was also an efficient antioxidant in both setups. However, pyridoxatin seems to be the most toxic from the hydroxamate group (composed also by the linear desferricoprogen and the aromatic desferriasterchrome). Other natural compounds have also been studied as possible candidates for iron-overload drug therapy. Iron complexes were characterized by spectrophotometry to assess the possible stoichiometry considering the binding sites for each compound. Fluorescence assays revealed that among the four compounds in study (chlorogenic acid, lapachol, hematein and hematoxylin), the complex between iron and hematein has higher relative stability than others


Assuntos
Sideróforos/análise , Sobrecarga de Ferro/terapia , Fluorescência , Espectrofotometria/instrumentação , Terapia por Quelação , Desferroxamina/classificação , Ferro/efeitos adversos , Antioxidantes
4.
Homeopatia Méx ; 87(715): 28-39, out. - dez. 2018.
Artigo em Espanhol | LILACS, HomeoIndex - Homeopatia | ID: biblio-995979

RESUMO

El aumento de la frecuencia de uso de los medicamentos homeopáticos en la población en general implica que la calidad en la elaboración de los mismos debe indagarse para evitar situaciones adversas en la población que los consume. En Colombia existen procesos legales para obtener el permiso de producción y venta; sin embargo, en éstos no hay verificación del producto terminado contrastándolo con un control. Los medicamentos homeopáticos se elaboran mediante ultradiluciones de sustancias que actúan basados en el principio similia similibus curantur. La Nux vomica es un medicamento homeopático de uso frecuente, dado su carácter de policresto para diferentes patologías, y por lo tanto es importante tener un control de calidad de dicho medicamento. En este estudio se realizaron mediciones de la concentración de Nux vomica 6CH, 7CH y 30CH comprada en diferentes farmacias (FAR) y vendida como producto terminado, comparándolos con un medicamento elaborado por las autoras de este trabajo, utilizando para ello la espectrofotometría UV/Vis, no encontrándose diferencias estadísticamente significativas entre ellos después de aplicar energía cinética. (AU)


The increasing use of homeopathic medicines in the general population implies that the quality in the preparation of those should be investigated to avoid adverse situations in the people who consumes them. In Colombia, there are legal processes to obtain the production and sale license, however, there is no verification of the finished product against a control. Homeopathic medicines are made by ultradilutions of substances that act based on the Similia similibus curentur principle. The Nux vomica is a homeopathic medicine of frequent use, given its character of policresto, for different pathologies and therefore it's important to have a quality control of that medication. In this study, measurements were made of Nux vomica 6CH, 7CH and 30CH concentration purchased in different pharmacies (FAR) and sold as a finished product, comparing them with a drug elaborated by the authors using UV/Vis spectrophotometry. No statistically significant differences were found between them. after applying kinetic energy. (AU)


Assuntos
Espectrofotometria , Qualidade dos Medicamentos Homeopáticos , Strychnos nux-vomica , Homeopatia , Colômbia
5.
Biosci. j. (Online) ; 34(5): 1365-1378, sept./oct. 2018.
Artigo em Inglês | LILACS | ID: biblio-967327

RESUMO

Moringa oleifera Lam. (Moringaceae) is a plant with several biological activities and therapeutic properties. However, the complete knowledge about its pharmacological, biological and ecological effects, and about the active components present in each vegetable part are not still completely elucidated. This study aimed to evaluate the antioxidant and photoprotective activities of different extracts from leaves and flowers of M. oleifera. These activities were assessed through in vitro tests, DPPH radical scavenging method, iron ion chelating effect (FRAP), lipid peroxidation (TBARS), nitric oxide scavenging method and assessment of the activity against the lipid peroxidation through hemolytic method. The photoprotective activity was assessed through spectrophotometric analysis and through in vitro test with Labsphere. It was also determined the extract's phenolic content and total flavonoid through spectrophotometry and HPLC. The obtained results demonstrated that this species have components with antioxidant and photoprotective potential mainly in the extracts obtained from fresh leaves and flowers. Therefore, it was possible to verify that M. oleifera has potential to be used as source of antioxidant components with photoprotective activity mainly due to the presence of phenolic components and among these, the flavonoids.


Moringa oleifera Lam. (Moringaceae) é uma planta com várias atividades biológicas e propriedades terapêuticas. No entanto, o conhecimento completo sobre seus efeitos farmacológicos, biológicos e ecológicos, e sobre os componentes ativos presentes em cada parte vegetal não são ainda completamente elucidados. Este estudo teve como objetivo avaliar as atividades antioxidantes e fotoprotetoras de diferentes extratos de folhas e flores de M. oleifera. Estas atividades foram avaliadas através de testes in vitro, método de eliminação de radicais DPPH, efeito de quelação de íons de ferro (FRAP), peroxidação lipídica (TBARS), método de eliminação de óxido nítrico e avaliação da atividade contra a peroxidação lipídica através do método hemolítico. A atividade fotoprotetora foi avaliada através de análise espectrofotométrica e através de teste in vitro com Labsphere. Também foi determinado o conteúdo fenólico do extrato e o flavonoide total através de espectrofotometria e HPLC. Os resultados obtidos demonstraram que esta espécie possui componentes com potencial antioxidante e fotoprotetor principalmente nos extratos obtidos a partir de folhas frescas e flores. Por conseguinte, foi possível verificar que a M. oleifera tem potencial para ser utilizado como fonte de componentes antioxidantes com atividade fotoprotetora principalmente devido à presença de componentes fenólicos e entre estes, os flavonoides.


Assuntos
Espectrofotometria , Protetores Solares , Flavonoides , Extratos Vegetais , Moringa oleifera
6.
Acta cir. bras ; 33(7): 565-576, July 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-949365

RESUMO

Abstract Purpose: To investigate the possible effects of argan oil on the healing of colorectal anastomoses. Methods: I n Group 1 (sham), laparotomy was performed and the colon was mobilized. In the control (Group 2) and argan oil (Group 3) groups, colonic resection and anastomosis were applied. To the control and sham groups, 2 mL of 0.9% NaCl was administred rectally, and in the argan oil group, 2 mL/day argan oil was applied rectally for 7 days. Results: The mean bursting pressures of the argan oil and sham groups were significantly higher than the values in the control group. A significant difference was determined between the tissue hydroxyproline and prolidase levels of control group and other groups. Histopathologically, argan oil showed significant beneficial effects on colonic wound healing. In the argan oil and sham groups, the tissue malondialdehyde and fluorescent oxidation product levels were found to be lower and total sulfhydryl levels were higher than the control group. Conclusions: The rectally administered argan oil was observed to have significantly ameliorated wound healing parameters and exerted a significant antioxidant effect. This is the first study in the literature about the beneficial effects of argan oil on colorectal anastomoses.


Assuntos
Animais , Feminino , Reto/cirurgia , Cicatrização/efeitos dos fármacos , Óleos Vegetais/uso terapêutico , Colo/cirurgia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Oxirredutases/análise , Reto/patologia , Espectrofotometria , Anastomose Cirúrgica , Distribuição Aleatória , Reprodutibilidade dos Testes , Colágeno/análise , Resultado do Tratamento , Ratos Wistar , Colo/patologia , Estresse Oxidativo/efeitos dos fármacos , Dipeptidases/análise , Ferida Cirúrgica/patologia , Ferida Cirúrgica/tratamento farmacológico , Hidroxiprolina/análise , Malondialdeído/análise
7.
Acta cir. bras ; 33(6): 508-517, June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-949360

RESUMO

Abstract Purpose: To compare the preventive effects of N-acetyl cysteine (NAC), ozone preconditioning and ozone treatment against contrast-induced nephropathy (CIN) in an experimental rat model. Methods: Thirty adult male Wistar rats were randomly distributed into five groups (n=6 for each group). Group I served as control and Group II had only contrast agent, while Group III received NAC and Group IV received intraperitoneal ozone 6 hours before and 6 hours after introduction of contrast agent. Ozone treatment was applied for 5 days after the contrast agent was introduced in Group V. After induction of CIN, groups were compared in terms of serum levels of urea, creatinine, neutrophil gelatinase associated lipocalin, protein carbonyl, total antioxidant capacity (TAC) as well as degree of renal injury at histopathologic level. Results: Groups II-V displayed more obvious histopathological alterations such as hemorrhage and renal tubular injury compared with Group I. TAC (p=0.043) and creatinine (p=0.046) levels increased significantly in Group II after the intervention. In Group III, protein carbonyl level diminished remarkably (p=0.046), while creatinine level was increased (p=0.046) following the intervention. TAC level was higher in Group IV (p=0.028) and Group V (p=0.026) following the procedure. Conclusion: The N-acetyl cysteine and ozone treatment may alleviate the biochemical and histopathological deleterious effects of contrast-induced nephropathy via enhancement of total antioxidant capacity and decreasing oxidative stress.


Assuntos
Animais , Masculino , Ozônio/farmacologia , Acetilcisteína/farmacologia , Meios de Contraste/efeitos adversos , Nefropatias/induzido quimicamente , Nefropatias/prevenção & controle , Antioxidantes/farmacologia , Valores de Referência , Espectrofotometria/métodos , Ureia/sangue , Ácido Ioxáglico/efeitos adversos , Distribuição Aleatória , Reprodutibilidade dos Testes , Resultado do Tratamento , Ratos Wistar , Estresse Oxidativo/efeitos dos fármacos , Creatinina/sangue , Carbonilação Proteica , Lipocalina-2/sangue , Rim/efeitos dos fármacos , Rim/patologia , Nefropatias/patologia
8.
Braz. dent. j ; 29(1): 82-87, Jan.-Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888716

RESUMO

Abstract The goal of this study was to evaluate in vitro the effect of the photoinitiator phenylpropanedione (PPD), alone or combined with camphorquinone (CQ), on color stability of photoactivated resin cements and their bond strength to ceramics using a micro-shear test. Four resin cements were used: a commercial brand cement (RelyX Veneer®) and 3 experimental cements with different types and concentration of photoinitiators. For color analysis, ceramic discs were cemented on bovine dentin specimens to simulate indirect restorations (n=8) and were exposed to UV for 120 h and tested for color alteration using a reflectance spectrophotometer and the CIEL*a*b* system. Data were analyzed by Anova and Tukey's test at 5% significance level. The color test results did not present statistically significant difference for the ∆E for all the studied cements, neither for ∆L, ∆a and ∆b. For the bond strength, all the studied cements showed statistically significant differences to each other, with the highest result for the RelyX Veneer® (29.07 MPa) cement, followed by the cement with CQ (21.74 MPa) and CQ+PPD (19.09 MPa) cement; the lowest result was obtained by the cement using only PPD as a photoinitiator (13.99 MPa). So, based on the studied parameters, PPD was not advantageous as photoinitiator of resin cements, because it showed a low value of bond strength to the ceramics and no superior color stability.


Resumo O objetivo deste estudo foi avaliar in vitro o efeito do fotoiniciador fenilpropanodiona (PPD), isoladamente ou em associação com a CQ, sobre a estabilidade de cor de cimentos resinosos fotoativados e sua resistência de união adesiva à cerâmica, por teste de microcisalhamento. Foram utilizados 4 cimentos resinosos, sendo um comercial (RelyX Veneer®) e 3 experimentais, diferindo entre si quanto ao tipo e concentração dos fotoiniciadores. Para a análise de cor foram cimentados discos cerâmicos sobre dentina bovina, simulando restaurações indiretas (n=8), sendo expostos a 120 h de UV e testados quanto às alterações de cor, que foram mensuradas empregando a escala CIEL*a*b*, por meio de espectrofotômetro de reflectância. Os dados obtidos foram verificados quanto à distribuição normal, submetidos a Anova e ao teste complementar Tukey, todos com significância de 5%. Os resultados do teste de cor não apresentam diferença estatisticamente significante para o ∆E dos 4 cimentos estudados, tampouco para ∆L, ∆a e ∆b. Para a resistência de união, todos os cimentos estudados apresentaram diferenças estatisticamente significantes entre si, com o maior resultado para o cimento comercial RelyX Veneer® (29,07 MPa), seguido pelo cimento com CQ (21,74 MPa), e cimento de CQ+PPD (19,09 MPa); o menor resultado foi obtido com o cimento utilizando apenas o PPD como fotoiniciador (13,99 MPa). Portanto, para os parâmetros estudados, o PDD não se mostrou vantajoso como fotoiniciador de cimentos resinosos, pois apresentou baixo valor de resistência de união à cerâmica e não demonstrou superioridade quanto à estabilidade de cor.


Assuntos
Animais , Bovinos , Colagem Dentária/métodos , Luz , Cimentos de Resina/química , Cor , Teste de Materiais , Espectrofotometria/métodos
9.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 247-253, Jan.-Feb. 2018. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-888089

RESUMO

Este trabalho se propôs a desenvolver um modelo preditivo para identificação de perda de estabilidade e de sedimentação em leite UAT por determinação da atividade enzimática de aminopeptidase no leite por espectrofotometria. Foram analisadas amostras de leite cru, pasteurizado e UAT após envase durante seis meses, na região Sul do Brasil. Acidez, crioscopia, gordura, extrato seco total, extrato seco desengordurado e densidade foram analisados nos leites cru e pasteurizado. Amostras de leite cru foram ainda submetidas à análise de contagem de psicrotróficos e à atividade de aminopeptidase, e amostras de leite UAT estocadas foram analisadas quanto ao grau de proteólise mediante análises sensoriais e atividade de aminopeptidase. Alterações sensoriais foram observadas em tempos de estocagem menores para amostras originadas de leite cru com contagem de psicrotróficos acima de 107 UFC mL-1. Não houve correlação entre a atividade de aminopeptidase e proteólise e também não foi observada correlação significativa entre os parâmetros físico-químicos e a ocorrência de proteólise no leite estocado. O modelo estudado não foi apto para predizer perda de estabilidade e ocorrência de proteólise no leite UAT.(AU)


The aim of this work was to develop a predictive model for identifying loss of stability and sedimentation in UHT milk by determining the enzymatic activity of aminopeptidasis in milk by spectrophotometry. Samples of raw milk, pasteurized and UHT after filling for 6 months in Southern Brazil were analyzed. Acidity, freezing point, fat, total solids, nonfat solids and density were analyzed in raw and pasteurized milk. Raw milk samples were also subjected to psychrotrophic count analysis and aminopeptidasis activity and UAT samples of stored milk were analyzed for degree of proteolysis through sensory analysis and aminopeptidasis activity. Sensory changes were observed in smaller storage time for samples of raw milk originated with psychrotrophic count above 107 CFU ml-1. There was no correlation between aminopeptidasis activity and proteolysis and there was also no significant correlation between physicochemical parameters and the occurrence of proteolysis in stored milk. The model was unable to predict loss of stability and occurrence of proteolysis in UHT milk.(AU)


Assuntos
Animais , Feminino , Bovinos , Aminopeptidases/análise , Leite/enzimologia , Proteólise , Bovinos , Espectrofotometria
10.
Pesqui. bras. odontopediatria clín. integr ; 18(1): 4122, 15/01/2018. ilus, tab
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-966914

RESUMO

Objective: To investigate the effect of home bleaching on color matching between the dental restoration and the adjacent tooth structure after the staining process. Material and Methods: Ten intact maxillary central incisors were used. After preparation (semimesial restoration of the specimens), the specimens were immersed in a colored solution for 14 days and then were washed and the bleaching process was there after performed. A spectrophotometer apparatus was used to determine the color of the specimens in the part of the tooth filled with restorative material three times, including before the staining process, fourteen days after the staining process and immediately after the bleaching process. Paired t-test was employed to compare the color of the intact tooth and the dental restoration before and after the staining and bleaching processes. The level of significance was set at 5%. Results: Pre-bleaching E color of the teeth was 68.1, which increased to 78.8% after bleaching, and this increase was also statistically significant (p<0.001). Pre and Post-bleaching E color of composite restorations was 65% and 77.6%, respectively. This increase was also statistically significant (p<0.001). Postbleaching E color of the tooth and composite material was 78.8% and 77.6%, respectively. This difference was not statistically significant (p=0.342). Conclusion: The staining and bleaching processes had a significant effect on the discoloration of the dental restoration and the tooth; however, the application of bleaching on the teeth and composite improved the tooth composite color-match.


Assuntos
Clareamento Dental , Descoloração de Dente , Resinas Compostas/administração & dosagem , Espectrofotometria/métodos , Estatísticas não Paramétricas , Incisivo , Irã (Geográfico)
11.
Pesqui. bras. odontopediatria clín. integr ; 18(1): 4242, 15/01/2018. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-967064

RESUMO

Objective: To investigate the effect of Arabic coffee on bleached teeth in comparison to black coffee. Material and Methods: Forty teeth (sound maxillary or mandibular premolars with no carious lesions) were randomly selected into 4 groups (A, B, C and D). One group (A) did not receive bleaching and was incubated in saline. The second group (B) was bleached and then incubated in saline. The last two groups were bleached and were immersed in either Arabic coffee (C) or black coffee (D). Color recording of the samples was always carried out as near to their mid-buccal surfaces as possible using VITA Easyshade Advance System. Color measurements were carried out using a digital spectrophotometer at baseline and after short-term and long-term immersion. Data were subjected to two way ANOVA and T-test. The level of significance was set at was set at 0.05. Results: Results show that immersion in Arabic coffee resulted only in significant reduction in the b* color value upon long-term immersion (i.e. a reduction in the yellow hue). Black coffee on the other hand resulted in significant: reduction in lightness, increased red tint and increased yellow hue altogether. Conclusion: The use of Arabic coffee did not deteriorate color, with the only significant change being the reduction of yellowish hue. Arabic coffee could be an alternative to black coffee after bleaching.


Assuntos
Arábia Saudita , Espectrofotometria/métodos , Clareamento Dental , Técnicas In Vitro/métodos , Café/efeitos adversos , Análise de Variância
12.
Arq. bras. med. vet. zootec. (Online) ; 70(5): 1649-1654, set.-out. 2018. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-947796

RESUMO

O objetivo deste trabalho foi analisar as leituras de composição do leite cru por meio de espectrofotometria FTIR, utilizando-se curva de regressão PLS, bem como as contagens de células somáticas e bacteriana total por citometria de fluxo, após adição de amido e sacarose. O leite cru foi adulterado com três concentrações de amido e sacarose (0,1%, 0,5% e 1%), colocado em frascos contendo bronopol ou azidiol, os quais foram armazenados em duas temperaturas (7±2°C e 25±2°C ). As análises foram realizadas após zero, três, 24, 48, 72 e 168 horas de armazenamento. O modelo de regressão linear múltipla foi utilizado para análise estatística. A adição de amido e sacarose resultou em mudança significativa (P<0,05) para todas as variáveis dependentes. O leite adulterado com amido resultou em aumento nas leituras de gordura, proteína, lactose, sólidos totais (ST), sólidos não gordurosos (SNG), CCS e CBT e em diminuição das leituras de caseína, do nitrogênio ureico do leite (NUL) e do ponto de congelamento. O leite adulterado com sacarose resultou no aumento das leituras da lactose, ST, SNG e NUL, enquanto as leituras de proteína, caseína, ponto de congelamento e CCS diminuíram. Este trabalho evidencia a importância do monitoramento de adulterantes reconstituintes no leite por afetarem os resultados analíticos da qualidade do leite, obtidos por métodos eletrônicos.(AU)


Assuntos
Análise de Fourier , Leite/química , Sacarose , Espectrofotometria/veterinária
13.
Rev. clín. periodoncia implantol. rehabil. oral (Impr.) ; 10(3): 145-148, dic. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-900296

RESUMO

ABSTRACT: Aim: The objective of this work was to determine the concentrations of irrigating solutions and the residual content of parachloroaniline (PCA) formed after endodontic irrigation, using 5% NaOCl, 0.9% NaCl, 10% EDTA and 2% CHX 2%. Methodology Twenty premolars were used and 13 samples were collected per tooth from each of the treatment phases. Samples of: NaOCl, EDTA, CHX and PCA were quantified by UV and visible spectrophotometry. Results: Sodium hypochlorite decreased its concentration from 3.8% to 3.4% in phases 1 to 4. In phases 5, 6 and 7, residual NaOCl was measured with concentrations of 0.007%, 0.003% and 0.001% %. The concentration of EDTA decreased to 8.85% in phase 8. In phases 9, 10 and 11, irrigated with serum, EDTA was quantified with concentrations of 0.013% to 0.002% and NaOCl values of 0.0011% to 0, 0006%. In phases 12 and 13, CHX concentrations were 1.850% and 1.812% and PCA values were 0.0005% and 0.0007%. PCA formation occurred in presence of 2% CHX and residual NaClO and was detected colorimetrically in phases 12 and 13. Conclusions. During endodontic irrigation the concentration of 5% NaOCl decreases significantly in the first four phases and the concentrations of EDTA and CHX also decrease. There is PCA training in the last stages of the procedure.


Assuntos
Humanos , Irrigantes do Canal Radicular/química , Hipoclorito de Sódio/química , Clorexidina/química , Compostos de Anilina/análise , Irrigantes do Canal Radicular/administração & dosagem , Hipoclorito de Sódio/administração & dosagem , Espectrofotometria , Clorexidina/administração & dosagem , Ácido Edético/química , Interações Medicamentosas , Endodontia
14.
Electron. j. biotechnol ; 29: 86-93, sept. 2017. graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1017388

RESUMO

Background: Although nanoparticles (NPs) have many advantages, it has been proved that they may be absorbed by and have toxic effects on the human body. Recent research has tried to evaluate and compare the nanotoxicity of gold nanoparticles (AuNPs) produced by two types of microorganisms in vitro by two different methods. AuNPs were produced by Bacillus cereus and Fusarium oxysporum, and their production was confirmed by visible spectral, transmission electron microscope, and X-ray diffraction (XRD) analyses. The human fibroblast cell line CIRC-HLF was treated with AuNPs, and the induced nanotoxicity was measured using direct microscopic and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Results: The results showed that the produced AuNPs had a maximum absorbance peak around 510­530 nanometer (nm), with spherical, hexagonal, and octagonal shapes and average sizes around 20­50 nm. The XRD results confirmed the presence of GNPs in the microbial culture supernatants. An MTT assay showed that GNPs had dose-dependent toxic effects, and microscopic analysis showed that GNPs induced cell abnormalities in doses lower than the determined half-maximal inhibitory concentrations (IC50s). Conclusions: In conclusion, the biologically produced AuNPs had toxic effects in the cell culture, and direct techniques such as microscopic evaluation instead of indirect methods such as MTT assay were more useful for assessing the nanotoxicity of the biologically produced AuNPs. Thus, the use of only MTT assay for nanotoxicity evaluation of AuNPs is not desirable.


Assuntos
Nanopartículas/metabolismo , Nanopartículas/toxicidade , Ouro/metabolismo , Ouro/toxicidade , Espectrofotometria , Bacillus cereus/metabolismo , Células Cultivadas , Compostos de Ouro/metabolismo , Compostos de Ouro/toxicidade , Testes de Toxicidade , Ressonância de Plasmônio de Superfície , Nanotecnologia , Microscopia Eletrônica de Transmissão , Nanopartículas Metálicas/toxicidade , Fusarium/metabolismo
15.
Mem. Inst. Oswaldo Cruz ; 112(8): 537-543, Aug. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-894863

RESUMO

BACKGROUND Silver nanoparticles (AgNPs) are increasingly being used in medical applications. Therefore, cost effective and green methods for generating AgNPs are required. OBJECTIVES This study aimed towards the biosynthesis, characterisation, and determination of antimicrobial activity of AgNPs produced using Pseudomonas aeruginosa ATCC 27853. METHODS Culture conditions (AgNO3 concentration, pH, and incubation temperature and time) were optimized to achieve maximum AgNP production. The characterisation of AgNPs and their stability were evaluated by UV-visible spectrophotometry and scanning electron microscopy. FINDINGS The characteristic UV-visible absorbance peak was observed in the 420-430 nm range. Most of the particles were spherical in shape within a size range of 33-300 nm. The biosynthesized AgNPs exhibited higher stability than that exhibited by chemically synthesized AgNPs in the presence of electrolytes. The biosynthesized AgNPs exhibited antimicrobial activity against Escherichia coli, P. aeruginosa, Salmonella typhimurium, Staphylococcus aureus, methicillin-resistant S. aureus, Acinetobacter baumannii, and Candida albicans. MAIN CONCLUSION As compared to the tested Gram-negative bacteria, Gram-positive bacteria required higher contact time to achieve 100% reduction of colony forming units when treated with biosynthesized AgNPs produced using P. aeruginosa.


Assuntos
Humanos , Prata/farmacologia , Contagem de Colônia Microbiana/métodos , Nanopartículas Metálicas/química , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Negativas/ultraestrutura , Bactérias Gram-Positivas/efeitos dos fármacos , Antibacterianos/biossíntese , Antibacterianos/farmacologia , Antibacterianos/química , Pseudomonas aeruginosa , Espectrofotometria , Microscopia Eletrônica/métodos
16.
Biosci. j. (Online) ; 33(4): 1106-1112, july/aug. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-966272

RESUMO

The color stability achieved by dental bleaching can be affected by exposure to staining agents present in foods. However, there is scarce research regarding tooth staining during dental bleaching. This study investigated the effect of pigments on the color stability of dental elements during dental bleaching. Blocks obtained from bovine incisors were divided into seven groups (n = 10) in accordance with the staining pigments (distilled water ­ control; coffee, cola, tea, red wine, chocolate milk and soya sauce (Shoyu). The color was evaluated with a spectrophotometer (Minolta CR-321, Japan) before and after dental bleaching (1st and 14th days), employing the (CIE) L*a*b* system. The dental bleaching procedure was performed using 22% carbamide peroxide gel applied to the sample surface for a period of 1 hour each day, for 14 days. After dental bleaching, the teeth were exposed to 20 ml of staining solution for 5 minutes, at 37ºC and 100 rpm for different periods. During the experiment, the samples were stored in distilled water. Data was analyzed using ANOVA followed by Tukey tests, with a significance level of 5%. Significant differences for E* values (p<0.05) were observed between the groups. The Shoyu group presented a decrease in luminosity (negative value of L*). It could be concluded that all solutions contained pigments that promoted staining on the surface. However, bleached enamel was susceptible to staining with soya sauce (Shoyu), while other substances did not interfere with the dental bleaching.


A estabilidade de cor conseguida por meio do clareamento dental pode ser afetada pela exposição à agentes pigmentantes presentes nos alimentos. Contudo, há uma escassa investigação sobre o manchamento dos dentes durante o clareamento dental. Este estudo investigou o efeito de agentes pigmentantes sobre a estabilidade da cor dos dentes durante o clareamento dental. Os blocos obtidos a partir de incisivos bovinos foram divididos em sete grupos (n = 10) de acordo com os agentes pigmentantes (água destilada - controle - café, cola, chá, vinho tinto, leite achocolatado e molho de soja - shoyu. A cor foi avaliada com um espectrofotômetro (Minolta CR-321, Japão) antes e após o clareamento (1º e 14º dias), utilizando o sistema (CIE) L*a*b*. O procedimento de clareamento dental foi realizado usando gel de peróxido de carbamida a 22% aplicado à superfície da amostra por um período de 1 hora por dia, durante 14 dias. Após o clareamento, os dentes foram expostos a 20 ml da solução pigmentante por 5 minutos, 37ºC e 100 rpm em diferentes períodos. Durante o experimento, as amostras foram armazenadas em água destilada. Os dados foram analisados por meio do teste ANOVA, seguido do Tukey, com nível de significância de 5%. Foram observadas diferenças significativas para os valores de E* (p <0,05) entre os grupos. O grupo Shoyu apresentou uma diminuição na luminosidade (valor negativo de L*). Pode-se concluir que todas as soluções que continham pigmentos promoveram manchamento superficial. No entanto, o esmalte clareado foi susceptível apenas ao manchamento com molho de soja (Shoyu), enquanto outras substâncias não interferiram no tratamento de clareamento dental.


Assuntos
Espectrofotometria , Clareamento Dental , Materiais Dentários
17.
J. appl. oral sci ; 25(3): 335-340, May-June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-893618

RESUMO

Abstract Objective This randomized, controlled, double-blind clinical study evaluated the effect of calcium sodium phosphosilicate (NovaMin) and casein phosphopeptide-amorphous calcium phosphate with fluoride (CPP-ACPF) on the prevention of post-operative sensitivity and on the effects of clinical bleaching treatment. Material and Methods Sixty volunteers were selected according to inclusion and exclusion criteria and were randomly assigned into three groups (n=20): CG (control group) patients, who were treated with 35% hydrogen peroxide; NOVAG (NovaMin group) patients, who were treated with 35% hydrogen peroxide followed by the application of NovaMin; and CPPG (CPP group) patients, who were treated with 35% hydrogen peroxide followed by the application of CPP-ACPF. Both bioactive agents were applied for five minutes. An evaporative stimulus associated with a modified visual scale was used to analyze sensitivity 24 hours after each bleaching session. The color evaluation was performed on the maxillary central incisors using a spectrophotometer. Associations between the intervention group, bleaching session, and reported sensitivity were tested using Chi-square partitioning. Results Color change values (ΔE) were analyzed using analysis of variance (ANOVA). The significance level used for both tests was 5%. In the intragroup assessment, the Friedman test showed that only the CPP-ACPF group showed no statistically significant difference (p<0.05) between baseline and first bleaching session. In the intergroup assessment, the Kruskal-Wallis test showed that the CPPG had less postoperative sensitivity after the first session, when compared to the other groups (p<0.05). Color change analysis (ΔE) showed a significant difference between the means obtained in the different bleaching sessions in all groups (p<0.05). Conclusions This study showed that the combination of CPP-ACPF with 35% hydrogen peroxide significantly reduced post-operative sensitivity in the first session, compared with the other evaluated treatments. The association of CPP-ACPF and NovaMin did not affect the color change induced by tooth bleaching.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Adulto Jovem , Caseínas/uso terapêutico , Dessensibilizantes Dentinários/uso terapêutico , Sensibilidade da Dentina/prevenção & controle , Fluoretos/uso terapêutico , Vidro/química , Clareamento Dental/efeitos adversos , Análise de Variância , Cor , Esmalte Dentário/efeitos dos fármacos , Método Duplo-Cego , Quimioterapia Combinada , Peróxido de Hidrogênio/efeitos adversos , Período Pós-Operatório , Reprodutibilidade dos Testes , Espectrofotometria , Fatores de Tempo , Clareadores Dentários/efeitos adversos , Resultado do Tratamento
18.
J. appl. oral sci ; 25(2): 147-158, Mar.-Apr. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-841181

RESUMO

Abstract Saliva when compared to blood collection has the following advantages: it requires no specialized personnel for collection, allows for remote collection by the patient, is painless, well accepted by participants, has decreased risks of disease transmission, does not clot, can be frozen before DNA extraction and possibly has a longer storage time. Objective and Material and Methods This study aimed to compare the quantity and quality of human DNA extracted from saliva that was fresh or frozen for three, six and twelve months using five different DNA extraction protocols: protocol 1 – Oragene™ commercial kit, protocol 2 – QIAamp DNA mini kit, protocol 3 – DNA extraction using ammonium acetate, protocol 4 – Instagene™ Matrix and protocol 5 – Instagene™ Matrix diluted 1:1 using proteinase K and 1% SDS. Briefly, DNA was analyzed using spectrophotometry, electrophoresis and PCR. Results Results indicated that time spent in storage typically decreased the DNA quantity with the exception of protocol 1. The purity of DNA was generally not affected by storage times for the commercial based protocols, while the purity of the DNA samples extracted by the noncommercial protocols typically decreased when the saliva was stored longer. Only protocol 1 consistently extracted unfragmented DNA samples. In general, DNA samples extracted through protocols 1, 2, 3 and 4, regardless of storage time, were amplified by human specific primers whereas protocol 5 produced almost no samples that were able to be amplified by human specific primers. Depending on the protocol used, it was possible to extract DNA in high quantities and of good quality using whole saliva, and furthermore, for the purposes of DNA extraction, saliva can be reliably stored for relatively long time periods. Conclusions In summary, a complicated picture emerges when taking into account the extracted DNA’s quantity, purity and quality; depending on a given researchers needs, one protocol’s particular strengths and costs might be the deciding factor for its employment.


Assuntos
Humanos , Masculino , Feminino , Saliva/química , DNA/isolamento & purificação , Controle de Qualidade , Kit de Reagentes para Diagnóstico , Valores de Referência , Manejo de Espécimes/métodos , Espectrofotometria , Fatores de Tempo , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Eletroforese
19.
J. appl. oral sci ; 25(2): 234-242, Mar.-Apr. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-841184

RESUMO

Abstract Regenerative endodontic procedure (REP) has been proposed as a new approach to treat immature permanent teeth. However, materials used in REP for root canal disinfection or cervical sealing may induce tooth discoloration. Objectives To assess tooth crown’s color after intracanal treatment with triple antibiotic paste (TAP) or calcium hydroxide (CH); cervical sealing with glass ionomer cement (GIC) or mineral trioxide aggregate (MTA); and bleaching with carbamide peroxide. Material and Methods After pulp removal and color spectrophotometer measurement, 50 bovine incisors were divided into 4 experimental groups and one control (untreated). Experiments were performed in phases (Ph). Ph1: TAP (ciprofloxacin, metronidazole, minocycline), TAPM (ciprofloxacin, metronidazole, amoxicillin), DAP (ciprofloxacin, metronidazole), or CH treatment groups. After 1 and 3 days (d); 1, 2, 3 weeks (w); and 1, 2, 3 and 4 months (m), color was measured and medications were removed. Ph2: GIC or MTA cervical sealing, each using half of the specimens from each group. Color was assessed after 1d, 3d; 1w, 2w, 3w; 1m and 2m. Ph3: Two bleaching sessions, each followed by color measurement. Data were analyzed with ANOVA and post-hoc Holm-Sidak method. Results Ph1: Specimens of TAP group presented higher color alteration (ΔE) mean than those of TAPM group. No significant difference was found among TAP or TAPM and CH, DAP or Control groups. Ph2: cervical sealing materials showed no influence on color alteration. Ph3: Different ΔE means (from different groups), prior to bleaching, became equivalent after one bleaching session. Conclusions TAP induces higher color alteration than TAPM; color alteration increases over time; cervical sealing material has no influence on color alteration; and, dental bleaching was able to recover, at least partially, the tooth crown’s color.


Assuntos
Animais , Bovinos , Antibacterianos/química , Materiais Restauradores do Canal Radicular/química , Irrigantes do Canal Radicular/química , Tratamento do Canal Radicular/métodos , Clareadores Dentários/química , Coroa do Dente/efeitos dos fármacos , Descoloração de Dente/induzido quimicamente , Compostos de Alumínio/química , Compostos de Cálcio/química , Hidróxido de Cálcio/química , Combinação de Medicamentos , Cimentos de Ionômeros de Vidro/química , Teste de Materiais , Óxidos/química , Peróxidos/química , Pigmentação em Prótese , Valores de Referência , Reprodutibilidade dos Testes , Silicatos/química , Espectrofotometria , Fatores de Tempo , Clareamento Dental/métodos , Ureia/análogos & derivados , Ureia/química
20.
J. oral res. (Impresa) ; 6(3): 61-63, Mar. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-907714

RESUMO

Abstract: Pulp tissue conditions such as infections have long been treated with calcium hydroxide (CaOH). In the last decade, use of mineral trioxide aggregate (MTA) has gained ground. This study was carried out to comparatively evaluate the Ca release from CaOH powder with different vehicles and different types of MTA. Materials and Methods: 40 single rooted mandibular premolars were selected, decoronated and biomechanically prepared. They were randomly divided into four groups, consisting of 10 samples each. Root canals were packed with different preparations of CaOH and MTA. Calcium ion release was evaluated with an UV-spectrophotometer. Result: Amongst the CaOH preparations, using propylene glycol as a vehicle produced extended release of calcium ions (7.34 +/- 0.01) for a period of 14 days. Whereas, amongst MTA based products, MTA angelus produced the maximum release of calcium ions (2.42 +/- 0.010). A statistically significant difference was present between the four groups (p<0.05). Conclusion: Propylene glycol mixed with CaOH powder, produces a higher and extended release of calcium ions compared to distilled water. MTA angelus produces consistent calcium ion release.


Assuntos
Agonistas dos Canais de Cálcio , Propilenoglicóis , Agentes de Capeamento da Polpa Dentária e Pulpectomia , Técnicas In Vitro , Solubilidade , Espectrofotometria
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