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1.
Braz. j. oral sci ; 23: e240869, 2024. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1537143

RESUMO

Aim: The aim of this study was to verify the color variation between different composite resins and the Vita Classical Shade Guide. Methods: Two-millimeter thickness samples were made (n = 6) from eight commercial brands of composite resin (shade A2): Charisma (Kulzer), Forma (Ultradent), Harmonize (Kerr), Luna (SDI), Opallis (FGM), Oppus Bulk Fill (FGM), Vittra (FGM) and Filtek Z250 XT (3M ESPE). Specimens were stored in distilled water for 7 days and then polished. Color measurements of samples and A2 shade of the Vita Classical Shade Guide were performed using the Vita Easy Shade Advance 4.0 spectrophotometer on a black background. Color variations were calculated using the CIEDE2000 formula, considering values ≥0.81 being noticeable by the human eye and ≥1.77 being clinically unacceptable. Results were statistically analyzed with a 5% significance level. Results: Color variation (ΔE) of composite (E1 ) compared to the Vita Classical Shade Guide (E0 ) was greater than clinically acceptable for all the materials evaluated in this study. Forma (ΔE=2.08 ± sd=0.47) and Filtek Z250 XT (2.50 ± 0.20) had the smallest amount of color variation values found in the results. Harmonize (3.32 ± 0.63) presented values similar to Filtek Z250 XT, but it was worse than Forma. Vittra (3.51 ± 0.28), Charisma (3.80 ± 0.20), Opallis (4.24 ± 0.30) and Luna (5.67 ± 0.20) did not differ among each other and presented higher color variation than Forma, Filtek Z350XT and Harmonize. Oppus Bulk Fill (13.94 ± 1.12) was the composite with the greatest color variation. Conclusions: The findings in this study show that attention should be taken when using the Vita Color Shade Guide for composite shade selection


Assuntos
Espectrofotometria , Água Destilada , Cor , Resinas Compostas
2.
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1529127

RESUMO

ABSTRACT Objective: To green synthesise gold nanoparticles using curcumin and to analyse its antioxidant, anti-inflammatory, and antimicrobial activity among oral pathogens. Material and Methods: Biosynthesised Curcumin Gold nanoparticles (CuAuNP) were evaluated by UV-visible spectrophotometer (UV-Vis), Transmission Electron Microscopy (TEM), and evaluation of antioxidant, anti-inflammatory and antibacterial activity against oral pathogens. Results: Synthesized CuAuNP were characterized using UV-visible spectrophotometry and showed peak absorption at 530nm. CuAuNp showed a 90.3% maximum scavenging ability of DPPH at a concentration of 50 μg/mL. CuAuNP exhibited 79.6 % of the highest anti-inflammatory activity at 50μg/mL than the standard drug diclofenac. TEM image clearly showed uniformly dispersed spherical-shaped gold nanoparticles with a size of about 20 nm. The biosynthesized nanoparticle was tested for its antimicrobial effect, and it showed a potent effect against S. aureus, E. faecalis, and C. albicans at 100µg/ mL. Enterococcus faecalis has a maximum zone of inhibition of 14 mm at 100µg/ mL of CuAuNp. Among gram-positive bacteria, a maximum zone of inhibition of 12 mm at 100µg/ mL was seen in S. aureus compared to S mutans. Candida albicans showed a maximum zone of inhibition of 18 mm at 25 μg/mL of CuAuNp. Conclusion: Curcumin-mediated gold nanoparticles with 20 nm size were effective and had strong antioxidant and anti-inflammatory activity at 50µg/ mL, antimicrobial action inhibiting microbes at 100µg/mL concentration that can be used in treating various Oral mucosal lesions.


Assuntos
Curcumina/efeitos adversos , Nanopartículas Metálicas/efeitos adversos , Anti-Infecciosos/efeitos adversos , Antibacterianos/efeitos adversos , Ácido Ascórbico , Espectrofotometria , Microscopia Eletrônica de Transmissão/instrumentação , Bactérias Gram-Positivas , Antioxidantes/efeitos adversos
3.
Braz. j. oral sci ; 22: e231377, Jan.-Dec. 2023. tab, ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1519248

RESUMO

The aim of this study was to investigate the influence of the quantity and positioning of feldspathic ceramic specimens inside the furnace on their flexural strength and translucency. The tested hypotheses were that the arrangement of specimens in the furnance would not influence 1) the translucency or 2) the biaxial strength of the porcelain. Methods: Ninety porcelain specimens were made (1.2 mm thickness and 13.5 mm diameter) and assigned into two main groups (n=15): G1 group - 15 firing cycles containing only one specimen each, always at the center of the refractory; and G5 group - 15 firing cycles containing five specimen each, where one specimen was at the center of the refractory and four specimens positioned equidistantly on the periphery. The translucency test was performed using a spectrophotometer, followed by the flexural strength test, according to ISO 6872:2015. T-student test was performed for both the mechanical and optical obtained data. Results: The flexural strength of the porcelain was not affected by the positioning (center x periphery) of the specimens inside the furnace (p =0.08), but the translucency was affected (periphery > center; p =0.009). Regarding to the number of feldspathic ceramic specimens, the biaxial flexural strength was affected (p =0.025), as well as the translucency (p <0.05). Conclusion: A higher quantity of feldspathic ceramic specimens for each firing cycle decreased its biaxial flexural strength and translucency. Also, specimens positioned at the center of the refractory became less translucent than those positioned at the periphery.


Assuntos
Humanos , Termodinâmica , Porcelana Dentária/química , Absorção Fisico-Química , Resistência à Flexão , Luz , Espectrofotometria , Temperatura , Teste de Materiais , Microscopia Eletrônica de Varredura , Fractografia
4.
Braz. j. oral sci ; 22: e231137, Jan.-Dec. 2023. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1523140

RESUMO

The purpose of this in vitro study was to analyze the influence of nicotine on the extracellular polysaccharides in Fusobacterium nucleatum biofilm. Methods: F. nucleatum (ATCC 10953) biofilms supplemented with different concentrations of nicotine (0, 0.5, 1, 2, 4, and 8 mg/mL) were grown in two different BHI broth conditions [no sucrose and 1% sucrose]. Extracellular polysaccharides assay, pH measurements, and a spectrophotometric assay were performed. Data were submitted for ANOVA and Tukey honestly significant difference analyses (HSD) tests (α =.05). Results: Extracellular polysaccharides synthesis was influenced by an interaction between nicotine concentrations and growth medium solution containing sucrose (P<.05). The pH values declined in the sucrose-exposed biofilm were greater than in the group exposed only to nicotine (P<.05). The biofilm exposed to sucrose and nicotine had a higher total biofilm growth (P<.05) than the nicotine-treated biofilm without sucrose. Conclusions: Regardless of sucrose exposure, biofilms exposed to different nicotine concentrations influenced the amount of extracellular polysaccharides


Assuntos
Humanos , Polissacarídeos Bacterianos/síntese química , Fusobacterium nucleatum/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Nicotina/farmacologia , Doenças Periodontais/microbiologia , Espectrofotometria , Sacarose/administração & dosagem , Meios de Cultura , Cárie Dentária/microbiologia , Nicotina/administração & dosagem
5.
Braz. J. Pharm. Sci. (Online) ; 59: e23059, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1505849

RESUMO

Abstract The addition of linseed (Linum usitatissimum Linn) in the diet, as a functional food, has increased over the years. However, it possesses cyanogenic glycosides. This study aimed to quantify and compare cyanide concentration in whole seed and bran of brown and golden types to establish a safe limit of intake. Three commercial labels, from brown and golden whole seed types (Ab, Ag, Bb, Bg, Cb and Cg), and six commercial labels of brown and golden bran (1b, 2g, 3g, 4b, 5g, and 6b), were selected, totalizing twelve samples. Total cyanide concentration was quantified by a colorimetric method employing alkaline picrate, after acid hydrolysis. The whole seed cyanide values were between 348.4 and 473.20 µg/g and the bran cyanide values were between 459.53 and 639.35 µg/g. The analyzed bran presented increased cyanide concentrations than the whole seeds with no differences between brown and golden types. Food able to produce cyanide less than 90 µg/kg body weight, daily, is considered secure for consumption. Considering this limit and analyzed samples, it is safe to eat approximately two tablespoons of seeds or one tablespoon of bran. These results point out the importance of cyanide amount daily intake information to be in linseed packaging, to ensure secure consumption


Assuntos
Sementes/efeitos adversos , Espectrofotometria/métodos , Linho/efeitos adversos , Cianetos/análise , Alimento Funcional/classificação
6.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1410309

RESUMO

En el presente trabajo se realiza la estandarización del procedimiento espectrofotométrico de determinación de polisacárido capsular e intermedios de Neisseria meningitidis serogrupo X, mediante la determinación de los grupos fosfodiéster presentes en su estructura, por el método de Chen. Se realizó un análisis de los siguientes criterios para la estandarización: linealidad, precisión (repetibilidad y precisión intermedia) y exactitud. Se demostró mediante el diseño experimental y los procedimientos estadísticos empleados que el método es lineal (r > 0,99), el coeficiente de variación del factor respuesta < 5 por ciento, la desviación estándar relativa de la pendiente < 2 por ciento, no existiendo diferencia estadísticamente significativa entre el intercepto de la ecuación con respecto a cero; exacto, porque no existe diferencia estadísticamente significativa entre la concentración determinada en un material de trabajo y su concentración nominal; también demostró ser repetible, pues el coeficiente de variación de las concentraciones de la muestra evaluada (2,44; 2,43; 0,88 por ciento para las concentraciones bajas, medias y altas, respectivamente) es inferior al 3 por ciento y no existen diferencias estadísticamente significativas entre las medias de los resultados obtenidos por dos analistas, evaluados durante cuatro días a tres niveles de concentración. La precisión intermedia es satisfactoria(AU)


The present work comprises the standardization a spectrophotometric procedure for assessing Neisseria meningitidis, serogroup X capsular polysaccharide and their intermediates of modification, the phosphodiesters groups present in its structure, based on Chen method. An analysis of the following standardization criteria was performed: linearity, precision (repeatability and intermediate precision) and accuracy. It was demonstrated through the experimental design and the statistical procedures used that the method is linear (r > 0.99), the coefficient of variation of the response factor < 5 percent, the relative standard deviation of the slope < 2 percent, with no statistically significant difference between the intercept of the equation with respect to zero; exact, because there is no statistically significant difference between the concentration determined in a work material and its nominal concentration; it also proved to be repeatable, because the coefficient of variation of the concentrations of the sample (2.44; 2.43; 0.88 percent for low, medium and high concentrations respectively) is less than 3 percent and there is no statistically significant difference between the means of the results obtained by two analysts, evaluated for four days at three concentration levels. Its intermediate precision was satisfactory(AU)


Assuntos
Humanos , Masculino , Feminino , Padrões de Referência , Espectrofotometria/métodos , Fatores de Virulência , Infecções Meningocócicas/diagnóstico , Infecções Meningocócicas/epidemiologia , Inibidores de Fosfodiesterase
7.
Natal; s.n; 17 ago. 2022. 80 p. tab, ilus, graf.
Tese em Português | LILACS, BBO - Odontologia | ID: biblio-1532937

RESUMO

A periodontite é uma condição crônica inflamatória que pode influenciar a microbiota intestinal. O tratamento padrão ouro para a periodontite inclui a raspagem e o alisamento corono-radicular (RACR), porém em casos complexos pode-se utilizar terapias adjuvantes, como os probióticos. A utilização deste tratamento adjuvante poderá contribuir para a melhoria da condição periodontal e a simbiose intestinal. O objetivo deste estudo foi avaliar o efeito na inflamação periodontal e intestinal da utilização do Lactobacillus casei (LC) adjunto a RACR em camundongos Balb/c com periodontite, induzida por ligadura. Este estudo é um ensaio pré-clínico, in vivo, randomizado, cego e controlado por placebo, constituído por 36 camundongos Balb/c machos. Os animais foram submetidos a indução da periodontite por colocação de ligadura com fio de seda 4.0 ao redor do segundo molar superior direito, sendo divididos em 4 grupos,o grupo controle: Sem Periodontite e sem RACR (n=8); Grupo Ligadura: Com Periodondite e sem RACR (n=10); Grupo raspagem: Com Periodontite e com RACR (n=10) ; Grupo raspagem + L.casei (n=8): Com Periodontite e com RACR + administração de LC, por gavagem, durante 30 dias. Foram realizadas análises de citocinas pelo método ELISA no tecido gengival (IL-6), intestinal (IL-1ß, IL-6 e IL-10) e sanguíneo (IL-1ß e IL-6), além de análises bioquímicas (TGO, TGP, ureia e creatinina) e contagem diferencial de leucócitos do sangue. Foram coletados fragmentos do intestino grosso desses animais e analisados quanto a biomarcadores do estresse oxidativo (SOD, GSH e MDA), atividade da acetilcolinesterase (AChE) e foi realizada contagem da população de Bactérias Produtoras de Ácido Láctico das fezes dos animais. A utilização do LC adjunto a RACR resultou em uma redução na expressão da IL-6 no tecido gengival de camundogos com Periodontite (p < 0,05). Para as inteleucinas séricas (IL-1ß e IL-6), não houve diferenças entre os grupos (p > 0,05). Já para as citocinas intestinais houve uma redução na expressão de IL-10 (p < 0,05), para os grupos em que foi induzida a Periodontite. Com relação ao estresse oxidativo intestinal os animais do Grupo raspagem e raspagem + LC tiveram uma redução dos níveis de MDA (p < 0,05), para a SOD e o GSH, não houve diferenças significativas entre os 4 grupos pesquisados (p < 0,05). Conclui-se que o uso de LC adjunto a RACR em camungongos com periodontite induzida por ligadura pode reduzir a liberação de IL-6 no tecido gengival. Com relação aos efeitos intestinais foi observada a modulação da resposta inflamatória, com a redução de MDA, nos animais que receberam o tratamento periodontal. E a redução da expressão da IL-10, nos animais com Periodontite (AU).


Periodontitis is a chronic inflammatory condition that can influence the gut microbiota. The gold standard treatment for periodontitis includes scaling and crown-root planing, but in complex cases adjuvant therapies such as probiotics can be used. The use of this adjuvant treatment may contribute to the improvement of periodontal condition and intestinal symbiosis. The aim of this study was to evaluate the effect on periodontal and intestinal inflammation of the use of Lactobacillus casei (LC) adjunct to scaling and root planing (RACR) in Balb/c mice with ligature-induced periodontitis. This study is a preclinical, in vivo, randomized, blinded, placebo-controlled trial consisting of 40 male Balb/c mice. The animals were submitted to periodontitis induction by placing a 4.0 silk suture ligature around the upper right second molar. The sample was divided into 4 groups, each with 10 animals: Group I: Without Periodontitis and without RACR; Group II: With Periodontitis and without RACR; Group III: With Periodontitis and with RACR; Group IV: With Periodontitis and with RACR + gavage of LC, for 30 days. Cytokine analyzes were performed by the ELISA method in gingival tissue (IL-6), intestinal tissue (IL-1ß, IL-6 and IL-10) and blood (IL-1ß and IL-6), the blood was also subjected to analysis biochemical (TGO, TGP, urea and creatinine) and differential leukocyte count. Fragments of the large intestine of these animals were collected and analyzed for biomarkers of oxidative stress (SOD, GSH and MDA), acetylcholinesterase (AChE) activity, and the population of Lactic Acid-Producing Bacteria in the animals' feces was counted. The use of LC adjunct to RACR resulted in a reduction in the expression of IL-6 in the gingival tissue of mice with Periodontitis (p < 0.05), for the blood inteleukins (IL-1ß and IL-6), there were no differences between the groups (p > 0.05). As for intestinal cytokines, there was a reduction in the expression of IL-10 (p < 0.05), for the groups that presented Periodontitis. Regarding intestinal oxidative stress, the animals in Groups III and IV had a reduction in MDA levels (p < 0.05), for SOD and GSH, there were no significant differences between the 4 groups studied (p < 0.05 ). It is concluded that the use of LC adjunct to RACR in mice with ligation-induced periodontitis can reduce the release of IL-6 in the gingival tissue. Regarding the intestinal effects, two effects were found: The first related to the modulation of the inflammatory response, with the reduction of MDA, in the animals that received periodontal treatment. And the second related to a pro-inflammatory effect, with the reduction of IL-10 expression (AU).


Assuntos
Animais , Camundongos , Periodontite/terapia , Lacticaseibacillus rhamnosus , Microbioma Gastrointestinal , Espectrofotometria/métodos , Análise de Variância , Estatísticas não Paramétricas , Estresse Oxidativo , Probióticos/uso terapêutico , Contagem de Leucócitos/métodos
8.
Int. j. high dilution res ; 21(2): 26-26, May 6, 2022.
Artigo em Inglês | LILACS, HomeoIndex - Homeopatia | ID: biblio-1396705

RESUMO

Drugs at high dilution (HD) produce therapeutic effect on man, animals and plants. Experimental evidence shows that free water molecules and hydrogen bond strength of OH groups constitute the physical basis of HDs which are otherwise devoid of original drug molecules. HDs are produced in aqueous EtOH by serial dilution of a substance with mechanical agitation or succussion in each step, and are called potencies. Three potencies 6 cH, 12 cH and 30 cH of two drugs Anacardium orientale and Natrum muriaticum(NaCl) and their mother tincture (MT) are used in this study. Electronic spectra of these MTs and potencies, all in 90% EtOH, were taken in the wavelength region of 190 nm ­350 nm. The objective is to find out any additional physical-chemical entities in potencies besides the aforesaid two factors. It was reported earlier that charge transfer (CT) interaction accompanies potentization of drugs. This study focused on the CT interaction. The results indicate that spectral pattern and absorbance intensities of the test samples vary from each other. Natm 6cH (absorbance 0.30 at 196.53nm), 12cH (abs. 0.06 at 196.53nm) and 30cH (abs. 1.32 at 196.5nm). Anac 6cH (abs. 0.33 at 203nm), 12cH (abs. 0.61 at 208nm) and 30cH (abs. 0.09 at 200.67nm). The spectrum of each potency shows two peaks. The 2nd peak at higher wave length belongs to CT interaction. Anac 6cH suc, 7cH unsuc. Insersections at 197.14nm with abs. 0.05, and 290nm with abs. 0.01. Anac 12cH suc, 13cH unsuc. Intersections at 196.93nm with abs. 0.06, and 273nm with abs. 0.00. Anac 30cH suc, 31cH unsuc. Intersections at 194.42nm with abs. -0.05, 238.03nm with abs. -0.01, 252.15nm with abs. -0.002, and 261nm with abs. 0.004. Natm 6cH suc, 7cH unsuc. Intersection at 199.44nm with Abs -0.11. Natm 12cH suc, 13cH unsuc. Instersection at 200.48nm with abs. -0.11. Natm 30cH suc, 31cH unsuc. Intersection at 204.24nm with abs. -0.08. Potentization involves CT interaction in consecutive potencies. Water and EtOH do not form a homogeneous mixture and have aggregates of EtOHand water molecules. CT interactions occur in these individual aggregates and are mostly inter molecular within EtOH or water. These aggregates vary from each other in the test samples. The spectra of test samples were analysed for margin of error (MOE). The MOE is very small (0.001-0.002%), and for this reason the difference between the spectra is significant. Besides that the intersection between consecutive spectra vary in number and position. It is concluded that water and EtOH aggregates and their relative distribution constitute additional physical-chemical basis of potencies.


Assuntos
Espectrofotometria , Escalas de Preparação , Medicamento Homeopático
9.
Alerta (San Salvador) ; 5(1): 64-73, ene. 28, 2022. tab
Artigo em Espanhol | BISSAL, LILACS | ID: biblio-1354468

RESUMO

Los trastornos hipertensivos asociados al embarazo constituyen uno de los síndromes de mayor interés a escala mundial, cerca de 600 000 mujeres mueren anualmente por causas relacionadas. La Organización Mundial de la Salud considera que la incidencia de preeclampsia es siete veces mayor en los países en vías de desarrollo en comparación a los industrializados (2,8 % y 0,4 %, respectivamente). El estrés oxidativo es una de las principales causas asociadas a la preeclampsia, cuyo diagnóstico y manejo adecuado y oportuno son medidas eficaces para disminuir la tasa de morbimortalidad, por lo que diversos autores se han centrado en la búsqueda de biomarcadores predictores de estrés oxidativo entre los cuales encontramos: especies reactivas del ácido tiobarbitúrico, superóxido, catalasa, superóxido dismutasa y glutatión peroxidasa. El presente trabajo describe los principales biomarcadores de estrés oxidativo estudiados mediante la técnica espectrofotométrica debido a que es económica, rápida y precisa


Hypertensive disorders associated with pregnancy are one of the syndromes of greatest interest worldwide, nearly 600,000 women die annually from related causes. The World Health Organization considers that the incidence of preeclampsia is seven times higher in developing countries compared to industrialized ones (2.8% and 0.4%, respectively). Oxidative stress is one of the main causes associated with preeclampsia, whose proper and timely diagnosis and management are effective measures to reduce the morbidity and mortality rate, which is why various authors have focused on the search for predictive biomarkers of oxidative stress among which we find: reactive species of thiobarbituric acid, superoxide, catalase, superoxide dismutase and glutathione peroxidase. The present work describes the main biomarkers of oxidative stress studied by means of the spectrophotometric technique because it is cheap, fast and precise


Assuntos
Pacientes , Pré-Eclâmpsia , Espectrofotometria , Mulheres , Estresse Oxidativo , Indicadores de Morbimortalidade , Morbidade , Métodos
10.
Pesqui. bras. odontopediatria clín. integr ; 22: e210044, 2022. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1365224

RESUMO

ABSTRACT Objective To assess the effects of coloring beverages on the color stability of two types of hybrid ceramics with different surface treatments. Material and Methods 180 specimens of two hybrid ceramics (Vita Enamic and Mazic Duro) and a feldspathic ceramic (Vita Mark II) were prepared (n=60 in each group). Half of the discs in each group were glazed while the other was polished. The specimens were then divided into three subgroups and immersed in distilled water, carrot juice, and coffee. The overall color difference (∆E) was calculated based on CIE L*a*b* color space. Data were analyzed using three-way and one-way ANOVA; Tukey's honest significant difference was also done for pairwise comparisons (α=0.05). Results Vita Mark II specimens revealed less overall color changes compared to other groups. The ∆E of the glazed Vita Enamic specimens was greater than polished specimens following immersion in distilled water (p=0.03) and coffee (p=0.001), but it was not significant for carrot juice. The same results were obtained for polished Mazic Duro specimens. Relatively similar amounts of ∆E were recorded in polished and glazed subgroups of Vita Mark II. Conclusion The ∆E of hybrid ceramics was higher than Vita Mark II. Polishing could be recommended for surface treatment of hybrid ceramics instead of glazing, saving time and facilitating the process.


Assuntos
Espectrofotometria/instrumentação , Propriedades de Superfície , Bebidas , Cor , Cimentos Dentários , Água Destilada , Cerâmica , Análise de Variância , Prótese Dentária , Desenho Assistido por Computador/instrumentação , Café , Porcelana Dentária , Corantes , Sucos de Frutas e Vegetais , Irã (Geográfico)/epidemiologia
11.
Braz. J. Pharm. Sci. (Online) ; 58: e19487, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1394028

RESUMO

Abstract Simple, precise, accurate and specific spectrophotometric methods are progressed and validated for concurrent analysis of Furosemide (FUR) and Spironolactone (SPR) in their combined dosage form depend on spectral analysis procedures. Furosemide (FUR) in the binary mixture could be analyzed at its λmax 274 nm using its recovered zero order absorption spectrum using constant multiplication method (CM). Spironolactone (SPR) in the mixture could be analyzed at its λmax 238 nm by ratio subtraction method (RS). Concurrent determination for FUR and SPR in their mixture could be applied by amplitude modulation method (AM), absorbance subtraction method (AS) and ratio difference (RD). Linearity ranges of FUR and SPR were (2.0µg/mL-22.0 µg/mL) and (3.0µg/mL-30.0 µg/mL), respectively. Specificity of the proposed spectrophotometric methods was examined by analyzing the prepared mixtures in laboratory and was applied successfully for pharmaceutical dosage form analysis which have the cited drugs without additives contribution. The proposed spectrophotometric methods were also validated as per as the guidelines of ICH. Statistical comparison was performed between the obtained results with those from the official methods of the cited drugs, using one-way ANOVA, F-test and student t-test. The results are exhibiting insignificant difference concerning precision and accuracy


Assuntos
Espectrofotometria/métodos , Espironolactona/antagonistas & inibidores , Preparações Farmacêuticas/administração & dosagem , Furosemida/antagonistas & inibidores , Análise de Variância , Formas de Dosagem , Métodos
12.
Braz. J. Pharm. Sci. (Online) ; 58: e20012, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1394034

RESUMO

Abstract Perindopril erbumine (Perindopril tert-butylamine salt) is a potent angiotensin-converting enzyme (ACE) inhibitor. It is used to treat the patients with hypertension and heart failure problems. A sensitive, inexpensive and precise analytical technique has been developed for the estimation of perindopril in bulk and formulations. The procedure involves the development of colour by forming an oxidative coupling reaction between drug (PPE) and reagent such as 2, 6-dichloroquinone-4-chlorimide (DCQC). The formed colored species were measured at (max=520 nm. The developed method showed linearity within the concentration limits of 25-75 µg mL-1. The linear correlation coefficient (r) and molar absorptivity were found to be 0.9999 and 3.285 x 103 mol-1cm-1. % Recovery ± SD values were in the range of 99.69 - 100.51 (+ 0.42 - ( 0.41) (n=3) which indicates the accuracy of the developed method. The interference of other excipients that are commonly present in formulations is found to be negligible. Precision and accuracy of the proposed method were confirmed by student t-test and F-tests at 95% confidence limits with (n-1) degrees of freedom. The validity parameters of proposed method were calculated by ICH guidelines


Assuntos
Perindopril , Acoplamento Oxidativo , Espectrofotometria/métodos , Angiotensinas/administração & dosagem , Preparações Farmacêuticas , Química Farmacêutica/classificação , Insuficiência Cardíaca
13.
Braz. J. Pharm. Sci. (Online) ; 58: e19519, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1383984

RESUMO

Abstract Silver nanoparticles (AgNPs) are among the most known nanomaterials being used for several purposes, including medical applications. In this study, Calendula officinalis L. flower extract and silver nitrate were used for green synthesis of silver nanoparticles under red, green and blue light-emitting diodes. AgNPs were characterized by Ultraviolet-Visible Spectrophotometry, Field Emission Scanning Electron Microscopy, Dynamic Light Scattering, Electrophoretic Mobility, Fourier Transform Infrared Spectroscopy and X-ray Diffraction. Isotropic and anisotropic silver nanoparticles were obtained, presenting hydrodinamic diameters ranging 90 - 180 nm, polydispersity (PdI > 0.2) and moderate stability (zeta potential values around - 20 mV)


Assuntos
Prata , Nitrato de Prata/agonistas , Calendula/efeitos adversos , Flores/genética , Nanopartículas/análise , Espectrofotometria/métodos , Difração de Raios X/métodos , Microscopia Eletrônica de Varredura/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Luz
14.
Braz. J. Pharm. Sci. (Online) ; 58: e19484, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1383994

RESUMO

Abstract Chronic type 2 diabetes mellitus (T2DM) and its associated diseases are major concern among human population and also responsible for significant mortality rate. Hence, the present study aims to evaluate and correlate the invertase inhibition, antioxidant activity and control against DFU causing bacterial pathogens by Pandanus odoratissimus flowers. Two dimensional preparative thin layer chromatography (2D PTLC) was adopted to purify the phenolic acid component and LC-MS2 was done to predict the phenolic acid structures. Standard spectrophotometry methods were adopted to investigate the in vitro invertase inhibitory and antioxidant (CUPRAC and ABTS) activities. Agar well diffusion and broth dilution assays were used to record the antibacterial property against DFU causing pathogens isolated from clinical samples. Statistical analyses were used to validate the experiments. A new and novel diferuloyl glycerate related phenolic acid (m/z 442) purified from PTLC eluate has recorded satisfactory cupric ion reducing power (ED50= 441.4±2.5 µg), moderate ABTS radical scavenging activity (IC50= 450.3±10 µg; 32.5±1.5%), and a near moderate, in vitro, invertase mixed type inhibition (24.5±4.5%; Ki: 400 µg). Similarly, bacterial growth inhibitory kinetics has showed a significant inhibition against E. coli and S. aureus.


Assuntos
Humanos , Masculino , Feminino , Técnicas In Vitro/métodos , Pé Diabético/patologia , Pandanaceae/efeitos adversos , Flores/classificação , beta-Frutofuranosidase/isolamento & purificação , Diabetes Mellitus Tipo 2/patologia , Espectrofotometria/métodos , Cromatografia em Camada Delgada/instrumentação , Antioxidantes/efeitos adversos
15.
Braz. j. oral sci ; 20: e211076, jan.-dez. 2021. tab
Artigo em Inglês | BBO - Odontologia, LILACS | ID: biblio-1253739

RESUMO

Aim: to evaluate the intra and inter-device reliability of two intraoral spectrophotometers in measuring the Commission Internationale de l'Éclairage (CIE) L*a*b* color coordinates and to compare the color difference (ΔE) between both devices. Methods: the central region of the labial surface of the maxillary central incisor of 31 participants was measured twice by each of the devices (VITA EasyShade and Degudent Shadepilot) by one examiner. CIE L*a*b* color coordinates were obtained for all teeth and ΔE was measured and compared. Intraclass correlation coefficient (ICC) and Mann-whitney U test were used to analyze the data (p<0.05). Results: inter-device reliability ICCs in measuring CIE L*a*b* color coordinates ranged between 0.08-0.49 with significant difference between devices only concerning the b coordinate (p<0.05). While intra device reliability ICCs ranged between 0.86-0.89 for VITA EasyShade and 0.81-0.86 for Degudent Shadepilot. The mean ΔE for CIE L*a*b* color coordinates of VITA EasyShade was 3.61 (±1.93) compared to 3.60 (± 1.45) for Degudent Shadepilot with insignificant difference between both devices (p>0.05). Conclusions: high intra device reliability in measuring CIE L*a*b* color coordinates was achieved particularly of Vita EasyShade, and both devices had clinically acceptable color difference (ΔE <3.7) however, inter device reliability was low to moderate. Consequently, the same spectrophotometer should be used throughout the steps of performing any tooth- colored restoration


Assuntos
Humanos , Masculino , Adulto , Espectrofotometria , Cor , Confiabilidade dos Dados
16.
Rev. Odontol. Araçatuba (Impr.) ; 42(2): 18-23, maio-ago. 2021. tab
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-1252902

RESUMO

O objetivo do estudo foi realizar uma revisão narrativa da literatura para comparar os métodos visual e instrumental de seleção da cor dentária, correlacionando-os com o fator experiência e a educação continuada. Utilizou-se como base de dados a MEDLINE na qual foram aplicados os descritores "visualshade match", "color measurement", "spectrophotometer" e "tooth color determination". Os critérios de inclusão foram artigos publicados entre 2010 e 2020que abordassem uma análise comparativa entre as duas modalidades de seleção da cor dentária. Se enquadraram nos critérios de exclusão estudos que não contemplavam a temática abordada e aqueles publicados nos anos anteriores a 2010, além das revisões de literatura. No total, onze artigos foram selecionados para compor essa revisão. Os estudos demonstraram que o método instrumental apresentou maior confiabilidade e reprodutibilidade quando comparado ao método visual, isso se deve ao fato de a escolha de cor através de instrumentos eletrônicos proporcionar melhor precisão e atenuação da subjetividade. No que concerne a experiência como fator influenciador da seleção de cor, os estudos são controversos. Mesmo evidenciando melhor precisão, a estimativa instrumental apresenta limitações devido à dificuldade de aferição em função da convexidade da anatomia dentária. Desse modo, foi descrito que a associação de métodos é capaz de elevar a confiabilidade da escolha de cor, melhorando o resultado estético. Não houve consenso entre os estudos com relação à influência da experiência, no entanto, a educação continuada foi sugerida na literatura como alternativa para formar profissionais mais confiantes no processo de seleção de tonalidades(AU)


The goal of this study was to carry out a narrative review of the literature to compare the visual and instrumental methods of tooth color selection, correlating them with the experience factor and continuing education. MEDLINE was used as a database in which the descriptions such as "visual shade match", "color measurement", "spectrophotometer" and "tooth color determination" were applied. The inclusion criteria were articles published between 2010 and 2020 that addressed a comparative analysis between the two types of tooth color selection. The exclusion criteria included studies that did not contemplate the theme addressed and those published in the years prior to 2010, in addition to literature reviews. In total, eleven articles were selected to compose this review. Studies have shown that the instrumental method showed greater reliability and reproducibility when compared to the visual method, this is due to the fact that the color's choice through electronic instruments provides better precision and lessened subjectivity. Regarding experience as na influencing factor in color selection, studies are controversial. Even with better precision, the instrumental estimation has limitations due to the difficulty of measuring it due to the convexity of the dental anatomy. Thus, it was described that the association of the methods is able to increase the reliability of the color's choice, improving the aesthetic result. There was no consensus among the studies in regard to the experiment's influence, however, continuing education was suggested in the literature as an alternative in order to form more confident professionals when it comes to the shade selection process(AU)


Assuntos
Cor , Estética Dentária , Espectrofotometria
17.
J. oral res. (Impresa) ; 10(4): 1-7, ago. 31, 2021. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1395270

RESUMO

The aim of this study is to evaluate the crown discoloration induced by bioceramic root canal filling materials (OrthoMTA and iRoot SP) compared to AH Plus. Material and Methods: Sixty intact mandibular single rooted premolars were sectioned 2 mm below the cemento-enamel junction, prepared, and randomly assigned into four groups according to the root filling materials: OrthoMTA, iRoot SP, AH Plus and unfilled. Results: Before placement of the materials in the pulp chamber and the coronal third of the root, the spectral reflectance lines of the crowns were recorded by a digital spectrophotometer at baseline, and after filling at 1 week and 1, 3 and 6 months and ∆Ε values were calculated. All materials used induced clinically perceptible crown discoloration (∆Ε>3.7) and no significant difference was detected between these materials (p>0.05). Regardless of the material, discoloration progressed significantly within the three months (p<0.05) however, at 6 months, the discoloration reduced for AH Plus and no further increase for bioceramic materials was detected. Conclusion: Bioceramic root filling materials tested induced clinically perceptible crown discoloration and their application in the esthetic zone should be performed with caution.


Objetivo: El objetivo de este estudio es evaluar la decoloración de la corona inducida por materiales biocerámicos de obturación del conducto radicular (OrthoMTA e iRoot SP) en comparación con AH Plus. Material y Métodos: Se seccionaron sesenta premolares mandibulares de raíz única intactos, 2 mm por debajo de la unión cemento-esmalte, se prepararon y se asignaron al azar en cuatro grupos de acuerdo con los materiales de obturación radicular: OrthoMTA, iRoot SP, AH Plus y sin relleno. Resultados:Antes de la colocación de los materiales en la cámara pulpar y el tercio coronal de la raíz, las líneas de reflectancia espectral de las coronas se registraron con un espectrofotómetro digital al inicio del estudio, y a la semana 1, así como a 1, 3 y 6 meses, y los valores ?? fueron calculados. Todos los materiales utilizados indujeron una decoloración de la corona clínicamente perceptible (??> 3,7) y no se detectaron diferencias significativas entre estos materiales (p> 0,05). Independientemente del material, la decoloración progresó significativamente dentro de los tres meses (p<0.05); sin embargo, a los 6 meses, la decoloración se redujo para AH Plus y no se detectó ningún aumento adicional para los materiales biocerámicos. Conclusiones: Los materiales biocerámicos de obturación radicular probados indujeron una decoloración de la corona clínicamente perceptible y su aplicación en la zona estética debe realizarse con precaución.


Assuntos
Humanos , Materiais Restauradores do Canal Radicular/efeitos adversos , Descoloração de Dente/induzido quimicamente , Espectrofotometria , Coroas , Esmalte Dentário , Cavidade Pulpar , Estética Dentária
18.
Medicina (Ribeirão Preto) ; 54(1)jul, 2021. fig.
Artigo em Português | LILACS | ID: biblio-1353725

RESUMO

RESUMO: Modelo do estudo: Trata-se de um estudo experimental in vitro com abordagem computacional. Objetivo: Ana-lisar a existência de interação entre as drogas hidrofóbicas bezafibrato e hidroclorotiazida com a hemoglobina a fim de prever alterações na biodisponibilidade das drogas, bem como na função proteica. Metodologia: Testes de interação in vitro entre a hemoglobina bovina e bezafibrato ou hidroclorotiazida foram realizados por espectrofo-tometria; análises dos sítios de interação e extrapolações para a hemoglobina humana foram feitas por técnicas de bioinformática. Resultados: Os testes in vitro demonstraram diminuição de absorbância (k) em 405 nm igual a 8,75 x 10-4 min-1 para o bezafibrato e 6,25 x 10-4 min--1 para a hidroclorotiazida. A diminuição sugere interação das drogas com a hemoglobina, sendo que o bezafibrato parece interagir com afinidade ligeiramente maior. As análises in silico mostraram que as drogas se ligam à porção proteica da hemoglobina. A constante de afinidade de ligação obtida por ancoragem molecular para o bezafibrato com a hemoglobina bovina (-8,3 kcal/mol) corrobora com o valor experimental de k e com o maior número de interações observadas, em relação à hidroclorotiazida (-6,6 kcal/mol). O mesmo padrão é observado para a interação do bezafibrato (-7,6 kcal/mol) e da hidroclorotiazida (-6,7 kcal/mol) com a hemoglobina humana. Conclusão: As técnicas de espectrofotometria e bioinformática utilizadas sugerem a possibilidade de interação da hemoglobina com drogas de natureza hidrofóbica, como bezafibrato e hi-droclorotiazida, sendo que essa interação pode afetar a função normal da hemoglobina e alterar a farmacodinâmica e farmacocinética das drogas prejudicando sua eficiência terapêutica. (AU)


ABSTRACT: Study model: It is an in vitro experimental study with a computational approach. Objective: Analyze the presence of interaction between hydrophobic drugs bezafibrate and hydrochlorothiazide and hemoglobin to predict bioavailability changes as well as in the protein function. Metodology: The in vitro tests to evaluate the interaction between the bovine hemoglobin and bezafibrate and hydrochlorothiazide were perfomed by spectrophotometry; bioinformatic tools made interaction analysis and extrapolation for human hemoglobin. Results: The in vitro tests showed a decrease in the absorbance (k) at 405 nm equal to 8.75 x 10-4 min-1 for bezafibrate and 6.25 x 10-4 min-1 for hydrochlorothiazide. The decrease suggests an interaction between the drugs and hemoglobin, for bezafibrate this interaction seems to be stronger than hydrochlorothiazide. The in silico analysis showed that the drugs bind to the protein portion of the hemoglobin. The binding affinity constant obtained by molecular docking from bezafibrate and bovine hemoglobin (-8.3 Kcal/mol) sustain the experimental value of k and the greater number of interactions observed in relation to hydrochlorothiazide (-6.6 kcal/mol). The same pattern was observed for interaction of bezafibrate (-7.6 kcal/mol) and hydrochlorothiazide (-6.7 kcal/mol) with human hemoglobin. Conclusion: The spectrophotometry and bioinformatic methods suggested the possibility of hemoglobin interaction with hydrophobic drugs such as bezafibrate and hydrochlorothiazide; this interaction could affect the normal function of hemoglobin and change the pharmacodynamics and pharmacokinetics of drugs impairing their therapeutic efficiency. (AU)


Assuntos
Espectrofotometria , Hemoglobinas , Biologia Computacional , Simulação de Acoplamento Molecular
19.
Arq. bras. med. vet. zootec. (Online) ; 73(3): 551-559, May-June 2021. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278350

RESUMO

The present study evaluated the use of haptoglobin (Hp) as an indicator of health and performance in 166 Holstein heifer calves reared in an intensive production system. Calves were evaluated at D6-9; D10-13; D20-23; D35-38 and D65-68, corresponding to the days of life. The absence or presence of diseases was evaluated by physical examination and classification of scores. The performance parameters evaluated were body weight, height at withers and hind width. Hp was measured by spectrophotometric technique. The highest prevalence of diarrhea (59.4%; 98/165) was observed in D10-13, bovine respiratory disease (BRD) was on D35-38 (25.8%; 42/163), and umbilical inflammations in D6-D9 (7.8%; 13/166). Highest values of Hp were observed in animals with diarrhea (P=0.02), and umbilical inflammation (P=0.057), in comparison with the group of healthy calves. A significant negative correlation was observed between Hp and performance index. This protein presented an important relation with diarrhea and performance of the calves, opening perspectives on its utilization as a biomarker of diseases.(AU)


O presente estudo avaliou o uso da haptoglobina (Hp) como indicadora de sanidade e desempenho em 166 bezerras Holandesas criadas em um sistema de produção intensivo. As bezerras foram avaliadas nos momentos D6-9; D10-13; D20-23; D35-38 e D65-68, sendo estes correspondentes aos dias de vida. A ausência ou a presença de doenças foi avaliada por meio do exame físico e da classificação por escores. Os parâmetros de desempenho avaliados foram peso corporal, altura de cernelha e largura de garupa. A Hp foi mensurada por técnica espectrofotométrica. A maior prevalência de diarreia (59,4%; 98/165) foi observada em D10-13, doença respiratória bovina (DRB) ocorreu em D35-38 (25,8%; 42/163) e inflamações umbilicais em D6-D9 (7,8%; 13/166). O valor de Hp foi maior nos animais que apresentaram diarreia (P=0,02) e inflamações umbilicais (P=0,057), em comparação ao grupo de bezerras saudáveis. Houve correlação negativa significativa entre a Hp e os índices de desempenho. Essa proteína apresentou uma importante relação com a diarreia e com o desempenho das bezerras, abrindo perspectivas sobre a sua utilização como biomarcadora de doenças.(AU)


Assuntos
Animais , Feminino , Bovinos , Haptoglobinas/análise , Proteínas de Fase Aguda/análise , Complexo Respiratório Bovino/patologia , Espectrofotometria/veterinária , Biomarcadores/análise , Diarreia/veterinária
20.
Rev. ADM ; 78(2): 73-79, mar.-abr. 2021. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1247336

RESUMO

El color es un efecto visual de los rayos de luz reflejándose y su concepto es complejo por ser una sensación que se percibe y por las características electromagnéticas. Los dientes varían espacialmente porque son curvados, tienen prolongaciones relativamente pequeñas y vistas en contra de una variable de fondo no uniforme así como típicamente una iluminación no estandarizada, por lo cual difieren en relación con su colorimetría, por lo que el estudio del color es fundamental en la odontología. En la actualidad hay métodos para evaluar el color, desde una simple revisión visual hasta instrumentos como el colorímetro y los espectrofotómetros, los cuales son aparatos utilizados en la medida del color de un objeto a través de su longitud de onda reflejada. Una pigmentación dental se produce por varios factores, ya sean intrínsecos y extrínsecos, estas pigmentaciones son factores importantes tanto en la estética como en el aspecto físico, por lo que es importante poder evaluar la estabilidad de los dientes naturales ante diferentes sustancias que podrían modificar su color natural. En este estudio nos dimos a la tarea de evaluar el cambio de color de dientes naturales ante diferentes bebidas, se eligieron tres bebidas pigmentantes y de uso común: café, vino tinto y jugo de arándano; se utilizaron 10 dientes unirradiculares del mismo color previamente analizados con el espectrofotómetro. Un diente fue la muestra control y los nueve restantes se sumergieron en frascos separados con 10 mL de las tres bebidas elegidas. Realizando la evaluación de color a los 15, 30 y 90 días con ayuda del espectrofotómetro, pudimos observar que el diente sumergido en café no tuvo variación durante los primeros 15 días y el cambio más notable de color fue hasta los 90 días a diferencia de las muestras sumergidas en vino y jugo de arándano cuya variación máxima de color se presentó en 15 días respectivamente (AU)


Color is a visual effect of light rays reflecting and its concept is complex, for being a sensation that is perceived and for the electromagnetic characteristics. Teeth vary spatially because they are curved, have relatively small extensions, and are viewed against a non-uniform background variable as well as typically non-standardized illumination, which is why they differ in relation to their colorimetry. So the study of color is fundamental in dentistry. Currently, there are methods to evaluate color, from a simple visual check to instruments such as the colorimeter and spectrophotometers, which are devices used to measure the color of an object through its reflected wavelength. A dental pigmentation is produced by various factors, both intrinsic and extrinsic, these pigmentations are currently important factors in both aesthetics and physical appearance, so it is important to be able to evaluate the stability of natural teeth against different substances that could modify its natural color. In this study, we undertook the task of evaluating the change in the color of natural teeth when faced with different beverages. Three pigment and commonly used beverages were chosen: coffee, red wine and cranberry juice; 10 single-rooted teeth of the same color previously analyzed with the spectrophotometer were used. One tooth was the control sample and the remaining nine were immersed in separate bottles with 10 mL of the three chosen drinks. Carrying out the color evaluation at 15, 30 and 90 days with the help of the spectrophotometer, we could see that the tooth immersed in coffee did not change during the first 15 days and the most notable change in color was up to 90 days, unlike the samples immersed in wine and cranberry juice whose maximum color variation was presented in 15 days respectively (AU)


Assuntos
Humanos , Descoloração de Dente , Bebidas , Cor , Colorimetria , Estética Dentária , Espectrofotometria/métodos , Vinho , Técnicas In Vitro , Epidemiologia Descritiva , Café , Sucos , Luz
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