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| Fragaki,Konstantina; Chaussenot,Annabelle; Benoist,Jean-François; Ait-El-Mkadem,Samira; Bannwarth,Sylvie; Rouzier,Cécile; Cochaud,Charlotte; Paquis-Flucklinger,Véronique. |
| BACKGROUND: Coenzyme Q10 (CoQ10 or ubiquinone) deficiency can be due either to mutations in genes involved in CoQ10 biosynthesis pathway, or to mutations in genes unrelated to CoQ10 biosynthesis. CoQ10 defect is the only oxidative phosphorylation disorder that can be clinically improved after oral CoQ10 supplementation. Thus, early diagnosis, first evoked by mitochondrial respiratory chain (MRC) spectrophotometric analysis, then confirmed by direct measurement of CoQ10 levels, is of critical importance to prevent irreversible damage in organs such as the kidney and the central nervous system. It is widely reported that CoQ10 deficient patients present decreased quinone-dependent activities (segments I + III or G3P + III and II + III) while MRC activities... |
| Tipo: Journal article |
Palavras-chave: Mitochondrial disease; CoQ10 deficiency; Respiratory chain; Spectrophotometry; LC-MSMS. |
| Ano: 2016 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602016000100004 |
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| Torres Ospina, Alexandra; Zapata, Julian Andrés; Gil Gonzalez, Jesus Humberto; Giraldo, Luis; Valencia, Diana Marcela. |
| One of the main factors to establish productivity of grazing cattle is the estimation of forage intake. For this, the most widely used technique is based on the estimation of fecal output using chromium dioxide as external marker. However, quantification can be expensive and sometimes not precise due to the methodology used for this purpose. Therefore, the aim of this study was to validate the colorimetric method for chromium quantification and to implement it in the estimation of fecal output in grazing cattle. The temperature, the digestion time and the wavelength for the measurement were evaluated. The method was validated for selectivity, linearity, detection and quantification limits, precision, accuracy, and stability. Results showed that... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Spectrophotometry; Fecal output; External marker; Chromium dioxide; Validation. spectrophotometry; Fecal output; External marker; Chromium dioxide; Validation.. |
| Ano: 2020 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/48096 |
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| Souza,Diego Mendes de; Morais,Pedro Augusto de Oliveira; Matsushige,Ivã; Rosa,Luismar Alves. |
| ABSTRACT Soil organic matter (SOM) is important to fertility, since it performs several functions such as cycling, water and nutrient retention and soil aggregation, in addition to being an energy requirement for biological activity. This study proposes new trends to the Embrapa, Walkley-Black, and Mebius methods that allowed the determination of SOM by spectrophotometry, increasing functionality. The mass of 500 mg was reduced to 200 mg, generating a mean of 60 % saving of reagents and a decrease of 91 % in the volume of residue generated for the three methods without compromising accuracy and precision. We were able to optimize conditions for the Mebius method and establish the digestion time of maximum recovery of SOM by factorial design and response... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: SOM; Spectrophotometry; Increase in functionality; Response surface. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832016000100419 |
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| Oliveira,Érika de Fátima Silva; Azevedo,Roberta de Cássia Pimentel; Bonfilio,Rudy; Oliveira,Diego Borges de; Ribeiro,Gislaine Pereira; Araújo,Magali Benjamim de. |
| Meloxicam is a broadly used drug in the therapeutics for the osteoarthritis and rheumatoid arthritis treatments in adults, and it is available in the Brazilian market, as tablet and capsule pharmaceutical forms. The present work aimed to establish conditions for accomplishment of the dissolution test of 15 mg meloxicam tablets (A and B test products), compared with the reference product, since there is no monograph about dissolution assays for meloxicam in official summaries. To optimize the conditions several parameters were tested and, according to obtained results, the use of pH 7.5 phosphate buffer (900mL, at 37 ± 0.5ºC) as dissolution medium, paddle method (apparatus 2), stirring speed of the dissolution medium at 100 rpm and collect time of 60... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Meloxicam/dissolution; Dissolution kinetics; Tablet pharmaceutical forms/dissolution test; Spectrophotometry. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-82502009000100008 |
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| Bado Nilles, A; Gagnaire, Beatrice; Thomas-guyon, Helene; Le Floch, S; Renault, Tristan. |
| The in vitro effects of polycyclic aromatic hydrocarbons (PAHs) on haemocyte and haemolymphatic parameters of the Pacific oyster, Crassostrea gigas, were tested using field concentrations (10(-7) and 10(-9) mg mL(-1)) observed in the Marennes-Oleron Basin (Charente-Maritime, France) and high concentrations (10(-3) and 10(-5) mg mL(-1)) observed during oil spills. As a first step, the effects of pollutants, after a 24 h contamination period, were monitored on individual and pooled haemolymph samples and similar results were observed for both sample types. In a second step, haemolymphs from 45 oysters were withdrawn and pooled. Eighteen pollutants were tested in vitro after a 4 and 24 h contamination period and 10 of them showed significant modulations of... |
| Tipo: Text |
Palavras-chave: Toxicity; PAHs; Pacific oyster; Spectrophotometry; Flow cytometry; Haemocyte activity. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4696.pdf |
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| Galvão,Marcos Aurelio Morais; Arruda,Alice Oliveira de; Bezerra,Isabelle Cristinne Ferraz; Ferreira,Magda Rhayanny Assunção; Soares,Luiz Alberto Lira. |
| ABSTRACT The stem bark and pods of “jucá” are widely used in Brazilian folk medicine and, despite their therapeutic relevancies, there are insufficient reports about their quality control. Both herbal drugs from the species are rich in tannins, which showed a lot of biological and economic interest. Thus, the purpose of this study was to evaluate the method for quantification of tannins in the stem bark and pods from L. ferrea. The performance of the method was tested against the influence of the most relevant parameters (reaction time; amount of drug; type and amount of precipitationagents; and, concentration of the reagents). The procedure was validated according to the literature. After optimization, the experimental conditions were established as: 30... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Libidibia ferrea; Quality control; Spectrophotometry; Tannins. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132018000100431 |
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| Tharpa,Kalsang; Basavaiah,Kanakapura; Rajedraprasad,Nagaraju; Vinay,Kanakapura Basavaiah; Hiriyanna,Salmara Ganeshbhat. |
| Two simple, sensitive, selective and inexpensive spectrophotometric methods are described for the determination of simvastatin (SMT) in bulk drug and in tablets using permanganate as the oxidimetric reagent. In method A, SMT is treated with a measured excess of permanganate in acetic acid medium and the unreacted oxidant is measured at 550 nm, whereas in method B the reaction is carried out in alkaline medium and the resulting manganate is measured at 610 nm. In method A, the amount of permanganate reacted corresponds to the SMT content and the absorbance is found to decrease linearly with the concentration; and in method B, the absorbance increases with concentration. The working conditions of assays were optimized, and the methods were validated... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Simvastatin assay; Spectrophotometry; Permanganate; Pharmaceutical products. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-82502010000100010 |
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| Zaia,Dimas Augusto Morozin; Marques,Fábio Rangel; Zaia,Cássia Thaïs Bussamra Vieira. |
| A comparative study between the biuret method (standard method for total proteins) and spectrophotometric methods using dyes (Bradford, 3',3",5',5"-tetrabromophenolphthalein ethyl ester-TBPEE, and erythrosin-B) was carried out for the determination of total proteins in blood plasma from rats. Bradford method showed the highest sensitivity for proteins and biuret method showed the lowest. For all the methods, the absorbance for different proteins (BSA, casein, and egg albumin) was measured and Bradford method showed the lowest variation of absorbance. The concentration of total protein obtained by using Bradford method was not statistically different (p>0.05) from concentration of total protein obtained by the biuret method. But in regard to erythrosin-B... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Total proteins; Spectrophotometry; Blood plasma; Dye-binding methods. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132005000300008 |
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| Labasque, Thierry; Chaumery, Christian; Aminot, Alain; Kergoat, Gilles. |
| The spectrophotometric iodine measurement for oxygen determination by the Winkler method is re-examined for theoretical and operational aspects. It is shown that the selection of an isobestic point for measuring the mixture of iodine and tri-iodide in the solution enhances reliability. The wavelength value of 466 nm was selected after a spectrum study. Then, performances are assessed by mean of statistical approach based on repeated standardization curves at the isobestic point compared with other wavelengths. At 466 nm, the method is linear up to about 1000 mumol kg(-1) of O-2. Optimization and validation of the spectrophotometric method is realized through a robustness study based on factors that may alter the results (temperature, reagent volumes,... |
| Tipo: Text |
Palavras-chave: Isobestic point; Sea water; Spectrophotometry; Dissolved oxygen. |
| Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-1694.pdf |
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| Brum,Karine Bonucielli; Haraguchi,Mitsue; Garutti,Mirella Biasoli; Nóbrega,Fernanda Nogarol; Rosa,Beneval; Fioravanti,Maria Clorinda Soares. |
| Brachiaria species contain steroidal saponins and are involved in outbreaks of hepatogenous photosensitization. This research presents the levels of a steroidal saponin, protodioscin, in the seeds and aerial parts of B. brizantha and B. decumbens during different developmental stages (growth, bloom, fructification and seed fall). The butanolic fraction of the ethanolic extract of each stage was submitted to thin layer chromatography (TLC) and spectrophotometric analysis through the Ehrlich reagent in 515nm. The chromatograms in TLC of the butanolic fraction of B. brizantha and B. decumbens showed similar spots as the protodioscin standard. The estimated level of protodioscin isomers in B. brizantha and B. decumbens ranged from 0.5% to 2.1%, having the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Brachiaria spp.; Photosensitization; Protodioscin; Spectrophotometry; Steroidal saponins. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782009000100049 |
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| Migliato,Ketylin Fernanda; Carvalho,Elisângela Simões de; Sacramento,Luis Vitor Silva do; Mello,João Carlos Palazzo de; Baby,André Rolim; Velasco,Maria Valéria Robles; Salgado,Hérida Regina Nunes. |
| A precise, accurate and low cost spectrophotometric method was developed and validated for routine determination of total polyphenols, as pyrogallic acid equivalents, from the percolated and lyophilized extract of Syzygium cumini (L.) Skeels fruits. Validation was assessed experimentally and data were rigorously treated by statistical analysis. Analytical parameters were: linearity, interval (range), precision and recovery/accuracy, limit of detection (LOD, μg mL-1) and limit of quantification (LOQ, μg mL-1). The visible spectrophotometric method presented linearity (r² = 0.9979 ± 0.0010) over the concentration range 0.25-7.5 μg mL-1 of standard pyrogallic acid, precision < 2.918171%, recovery/accuracy ranging from 96.228693 to 107.17701%, LOD = 0.21 μg... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Total polyphenols; Syzygium cumini; Botanical extract; Analytical method validation; Spectrophotometry. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-82502009000100015 |
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| Registros recuperados: 20 | |
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