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1.
Arq. bras. oftalmol ; 87(3): e2022, 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1550036

RESUMO

ABSTRACT Purpose: This study aimed to investigate the effect of upper eyelid blepharoplasty with the removal of the skin and a strip of orbicularis oculi muscle on the ocular surface, tear film, and dry eye-related symptoms. Methods: Twenty-two eyes of 22 consecutive patients operated by a single surgeon (21 females; mean age, 61 years; age range, 41-75 years) were included. All subjects completed the Ocular Surface Disease Index questionnaire, underwent in vivo confocal microscopy, tear film breakup time measurements, the Schirmer test with anesthesia, and fluorescein and lissamine green staining measurements before, 1 month, and 6 months after upper blepharoplasty alone with preseptal orbicularis excision. Results: A significant increase in Ocular Surface Disease Index, and corneal fluorescein and lissamine green staining and a significant decrease in tear film breakup time were observed after 1 month (p=0.003, p=0.004, p=0.029, and p=0.024 respectively) and 6 months (p=0.001 for all findings). No significant difference in the Schirmer test score was observed during the follow-up. None of the in vivo confocal microscopy parameters showed significant changes during the study. Conclusions: An increase in dry eye symptoms and a decrease in tear film stability along with ocular surface staining were observed in patients undergoing upper eyelid blepharoplasty.

2.
Rev. nav. odontol ; 50(1): 15-20, jun. 2023.
Artigo em Português, Inglês | LILACS-Express | LILACS | ID: biblio-1517924

RESUMO

O tratamento estético de dentes com alteração de cor é um grande desafio na Odontologia Restauradora. Nesse sentido, a utilização de técnicas de estratificação com resina composta associada ao uso de pigmentos opacificadores permite que seja possível restaurar por meio de uma técnica direta, que resulta em um menor desgaste da estrutura dental durante o preparo. Dessa forma, o presente trabalho apresenta um caso clínico de faceta direta de resina composta utilizando associação de três pigmentos opacificadores. Paciente do sexo masculino, 54 anos, procurou atendimento apresentando alteração de cor severa do dente 21, relato de trauma dental, tratamento endodôntico e contraindicação de novo protocolo de clareamento interno, sendo sugerido, como plano de tratamento, a restauração direta com resina composta. Para a confecção da faceta direta de resina, foi utilizada uma mistura de três opacificadores na consistência fluida. Para verificar o valor da camada aplicada da mistura, foram feitas fotografias em preto e branco. A estratificação prosseguiu com camadas de resina translúcida para a base palatina, resina opaca de dentina e resina acromática translúcida para o esmalte. Como resultado, constatou-se a função e eficácia do uso da associação de pigmentos opacificadores na resolução do caso, em seguida, foi realizada uma reavaliação após 30 dias e 7 meses do procedimento restaurador, quando verificou-se a estabilidade de cor da restauração. Concluiu-se, portanto, que a utilização da técnica de estratificação de resinas compostas associada a utilização de pigmentos opacificadores traz resultados estéticos satisfatórios e favoráveis por meio de uma técnica direta, realizada em sessão clínica única e com alta previsibilidade.


The esthetic treatment of teeth with discoloration is a major challenge in restorative dentistry. In this sense, the use of composite resin veneering techniques associated with the use of opacifying stains allows restorations to be made using a direct technique, which results in less wear to the tooth structure during preparation. Thus, the present study presents a clinical case of a direct composite resin veneer using an association of three opacifying pigments. A 54-year-old male patient presented with severe color change on the central upper left incisor, a report of dental trauma, endodontic treatment, and contraindication for a new internal bleaching protocol. In order to make the direct resin veneer, a mixture of three opacifiers in a fluid consistency was used. To check the value of the applied layer of the mixture, black and white photographs were taken. Layering proceeded with translucent resin layers for the palatal base, opaque dentin resin and translucent achromatic resin for the enamel. As a result, the function and efficacy of the use of the association of opacifying pigments was verified in the resolution of the case. A reevaluation was performed 30 days and 7 months after the restorative procedure, when the color stability of the restoration was verified. This case allows to conclude that using composite resin layering technique associated with the use of opacifying pigments brings satisfactory and favorable aesthetic results through a direct technique, performed in a single clinical session and with high predictability.

3.
Indian J Ophthalmol ; 2023 May; 71(5): 2323
Artigo | IMSEAR | ID: sea-225073

RESUMO

Background: Dyes are substances that are an integral part of ocular procedures and surgeries. In Clinical practice, dyes help in better visualization and aid in diagnoses of ocular surface disorders. In Surgical practice, dyes help in better resolution of the structures that are otherwise naked to the surgeon’s eyes. Purpose: To educate ophthalmologists about the importance and uses of dyes. Synopsis: Dyes have become an important part of an ophthalmologists' clinical as well as surgical practice. This video aims at educating the different characteristics, uses, advantages and disadvantages of each dye. Dyes help in identifying the obscure and highlighting the invisible. The indications and contraindications as well as the side effects of each dye are discussed which would help ophthalmologists in the correct usage of these wonder substances. This video will also help the new eye doctors understand and utilize these dyes judiciously which would aid in their learning process and provide better patient care. Highlights: This video highlights the uses, indications, contraindications and side effects of all the dyes used in ophthalmology

4.
Indian J Biochem Biophys ; 2023 Apr; 60(4): 320-330
Artigo | IMSEAR | ID: sea-221642

RESUMO

Dyes are becoming more widely used around the world wide, but there is no effective bioremediation approach for removing them completely from the environment. Several dyes are mentioned to be degraded through bacteria; however, it's still unknown how the particular enzymes act throughout the dye degradation. The behavior and function of these enzymes in the biodegradation of azo dyes (Textile dyes) had been investigated experimentally by the numbers of the researchers, however, the molecular mechanisms remain unclear. Therefore, the interaction mechanisms of textile dye (methyl orange) with laccase from B. subtilis were explored through molecular docking and molecular dynamics simulations, the three selected dyes (methyl orange, malachite green, and acid blue 62) that interact positively with laccase on the basis of their maximum binding energy, molecular docking results indicate that one of the three dyes is more stable as a target for degradation through Bacillus subtilis laccase. Therefore, subsequent research focused solely on one substrate: methyl orange. Molecular Dynamics simulation study was applied after the molecular docking to determine the interaction between laccases and methyl orange dyes. The trajectory was proved with root mean square deviation and root mean square fluctuation analysis. According to the molecular dynamics simulation results, laccase-methyl orange complexes remain stable during the catalytic reaction. So, this study demonstrates how laccase is involved in methyl orange bioremediation.

5.
Braz. j. biol ; 83: 1-5, 2023. ilus, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468990

RESUMO

Behavioral lab bioassays involving termites must be promptly performed to allow intended observations prior to death from dissecation, typical of these soft-bodied insects. To this end, topic markers have been proposed as an alternative to histological stains which, while not always toxic are inevitably lengthy to apply. Among recommended topic markers, gouache is easy to apply, dries out quickly, but it is known affect termites in the long run, being suitable only to short-term bioassays. Its alternative, colored glue, is also easy to apply, but it takes long to dry and it is too dense and heavy, being thus prone to affect termite walking patterns. Here we tested a mix of gouache and colored glue aiming to combine the qualities of both into a suitable topical marker for Cornitermes cumulans termites. Similar patterns of survival presented by marked and unmarked termites ruled out concerns about toxicity of this mixture. Such results were consistent across distinct group densities evidencing that the mixture does not interfere with, nor it is affected by, crowding effects. Because crowding regulates interindividual interactions and these underlie most behaviors, the mixture can be thought to be suitable to behavioral studies. We argue that this 1:2 glue:gouache mixture is an excellent alternative to mark termites for lab bioassays. Being atoxic, cheap, easy to apply, and non-invasive, this mixture may happen to be useful not only for termites but also in bioassaying other similarly soft-bodied insects.


Bioensaios comportamentais em laboratório com cupins devem ser realizados rapidamente a fim de garantir observações antes da morte por dissecação, típico desses insetos de corpo mole. Para este fim, marcadores tópicos têm sido propostos como uma alternativa para marcadores histológicos que, embora nem sempre tóxico, possuem uma aplicação demorada. Entre os marcadores tópicos recomendados, tinta guache é de fácil aplicação, rápida secagem, porém afeta os cupins em bioensaios longos, sendo adequado apenas para bioensaios curtos. Sua alternativa, cola colorida, também é de fácil aplicação mas leva muito tempo para secar e é muito denso e pesado, afetando os padrões de caminhamento dos cupins. No presente estudo, nós testamos uma mistura de tinta guache e cola colorida objetivando combinar as qualidades de ambos os marcadores tópicos em um marcador tópico adequado para Cornitermes cumulans. Padrões similares de sobrevivência entre cupins marcados e controle indicam a ausência de toxicidade na mistura de tinta guache e cola colorida. Tais resultados são consistentes em grupos de densidades distintas, o que comprova que a mistura não interfere, nem sofre efeitos de aglomeração. Uma vez que a aglomeração regula as interações inter-individuais e afetam a maioria dos comportamentos, a mistura pode ser adequada para estudos comportamentais. Nós argumentamos que a mistura de tinta guache e cola (1:2) é uma excelente alternativa como marcador tópico em cupins para bioensaios em laboratório. Sendo atóxico, barato, fácil de aplicar e não invasivo, esta mistura pode ser útil não só para os cupins, mas também em bioensaios com outros insetos de corpo mole.


Assuntos
Animais , Bioensaio/métodos , Bioensaio/veterinária , Isópteros
6.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469208

RESUMO

Abstract Behavioral lab bioassays involving termites must be promptly performed to allow intended observations prior to death from dissecation, typical of these soft-bodied insects. To this end, topic markers have been proposed as an alternative to histological stains which, while not always toxic are inevitably lengthy to apply. Among recommended topic markers, gouache is easy to apply, dries out quickly, but it is known affect termites in the long run, being suitable only to short-term bioassays. Its alternative, colored glue, is also easy to apply, but it takes long to dry and it is too dense and heavy, being thus prone to affect termite walking patterns. Here we tested a mix of gouache and colored glue aiming to combine the qualities of both into a suitable topical marker for Cornitermes cumulans termites. Similar patterns of survival presented by marked and unmarked termites ruled out concerns about toxicity of this mixture. Such results were consistent across distinct group densities evidencing that the mixture does not interfere with, nor it is affected by, crowding effects. Because crowding regulates interindividual interactions and these underlie most behaviors, the mixture can be thought to be suitable to behavioral studies. We argue that this 1:2 glue:gouache mixture is an excellent alternative to mark termites for lab bioassays. Being atoxic, cheap, easy to apply, and non-invasive, this mixture may happen to be useful not only for termites but also in bioassaying other similarly soft-bodied insects.


Resumo Bioensaios comportamentais em laboratório com cupins devem ser realizados rapidamente a fim de garantir observações antes da morte por dissecação, típico desses insetos de corpo mole. Para este fim, marcadores tópicos têm sido propostos como uma alternativa para marcadores histológicos que, embora nem sempre tóxico, possuem uma aplicação demorada. Entre os marcadores tópicos recomendados, tinta guache é de fácil aplicação, rápida secagem, porém afeta os cupins em bioensaios longos, sendo adequado apenas para bioensaios curtos. Sua alternativa, cola colorida, também é de fácil aplicação mas leva muito tempo para secar e é muito denso e pesado, afetando os padrões de caminhamento dos cupins. No presente estudo, nós testamos uma mistura de tinta guache e cola colorida objetivando combinar as qualidades de ambos os marcadores tópicos em um marcador tópico adequado para Cornitermes cumulans. Padrões similares de sobrevivência entre cupins marcados e controle indicam a ausência de toxicidade na mistura de tinta guache e cola colorida. Tais resultados são consistentes em grupos de densidades distintas, o que comprova que a mistura não interfere, nem sofre efeitos de aglomeração. Uma vez que a aglomeração regula as interações inter-individuais e afetam a maioria dos comportamentos, a mistura pode ser adequada para estudos comportamentais. Nós argumentamos que a mistura de tinta guache e cola (1:2) é uma excelente alternativa como marcador tópico em cupins para bioensaios em laboratório. Sendo atóxico, barato, fácil de aplicar e não invasivo, esta mistura pode ser útil não só para os cupins, mas também em bioensaios com outros insetos de corpo mole.

7.
Chinese Journal of Biotechnology ; (12): 472-487, 2023.
Artigo em Chinês | WPRIM | ID: wpr-970386

RESUMO

Flow cytometry is a multi-parameter, rapid and efficient method for qualitative analysis and quantitative determination of various fluorescently labeled particles in liquid flow. Flow cytometry has been applied in multiple disciplines such as immunology, virology, molecular biology, cancer biology and infectious disease monitoring. However, the application of flow cytometry in plant research is hampered due to the special composition and structure of plant tissues and cells, such as cell walls and secondary metabolites. In this paper, the development, composition and classification of flow cytometry were introduced. Subsequently, the application, research progress and application limitations of flow cytometry in plant field were discussed. At last, the development trend of flow cytometry in plant research was prospected, which provides new perspectives for broadening the potential application scope of plant flow cytometry.


Assuntos
Citometria de Fluxo/métodos , Plantas , Corantes Fluorescentes
8.
International Journal of Surgery ; (12): 423-426, 2023.
Artigo em Chinês | WPRIM | ID: wpr-989475

RESUMO

Near-infrared fluorescence imaging (NIRFI) is a new noninvasive detection and diagnosis technology, with the continuous development of NIRFI technology, now widely used in the clinic, characterized by high sensitivity, high penetration, no harmful radiation and simple equipment operation. This article describes the recent applications of NIRFI in the diagnosis and treatment of breast cancer and looks at future developments and perspectives in this field.

9.
Braz. j. biol ; 83: e03316, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345530

RESUMO

Abstract Behavioral lab bioassays involving termites must be promptly performed to allow intended observations prior to death from dissecation, typical of these soft-bodied insects. To this end, topic markers have been proposed as an alternative to histological stains which, while not always toxic are inevitably lengthy to apply. Among recommended topic markers, gouache is easy to apply, dries out quickly, but it is known affect termites in the long run, being suitable only to short-term bioassays. Its alternative, colored glue, is also easy to apply, but it takes long to dry and it is too dense and heavy, being thus prone to affect termite walking patterns. Here we tested a mix of gouache and colored glue aiming to combine the qualities of both into a suitable topical marker for Cornitermes cumulans termites. Similar patterns of survival presented by marked and unmarked termites ruled out concerns about toxicity of this mixture. Such results were consistent across distinct group densities evidencing that the mixture does not interfere with, nor it is affected by, crowding effects. Because crowding regulates interindividual interactions and these underlie most behaviors, the mixture can be thought to be suitable to behavioral studies. We argue that this 1:2 glue:gouache mixture is an excellent alternative to mark termites for lab bioassays. Being atoxic, cheap, easy to apply, and non-invasive, this mixture may happen to be useful not only for termites but also in bioassaying other similarly soft-bodied insects.


Resumo Bioensaios comportamentais em laboratório com cupins devem ser realizados rapidamente a fim de garantir observações antes da morte por dissecação, típico desses insetos de corpo mole. Para este fim, marcadores tópicos têm sido propostos como uma alternativa para marcadores histológicos que, embora nem sempre tóxico, possuem uma aplicação demorada. Entre os marcadores tópicos recomendados, tinta guache é de fácil aplicação, rápida secagem, porém afeta os cupins em bioensaios longos, sendo adequado apenas para bioensaios curtos. Sua alternativa, cola colorida, também é de fácil aplicação mas leva muito tempo para secar e é muito denso e pesado, afetando os padrões de caminhamento dos cupins. No presente estudo, nós testamos uma mistura de tinta guache e cola colorida objetivando combinar as qualidades de ambos os marcadores tópicos em um marcador tópico adequado para Cornitermes cumulans. Padrões similares de sobrevivência entre cupins marcados e controle indicam a ausência de toxicidade na mistura de tinta guache e cola colorida. Tais resultados são consistentes em grupos de densidades distintas, o que comprova que a mistura não interfere, nem sofre efeitos de aglomeração. Uma vez que a aglomeração regula as interações inter-individuais e afetam a maioria dos comportamentos, a mistura pode ser adequada para estudos comportamentais. Nós argumentamos que a mistura de tinta guache e cola (1:2) é uma excelente alternativa como marcador tópico em cupins para bioensaios em laboratório. Sendo atóxico, barato, fácil de aplicar e não invasivo, esta mistura pode ser útil não só para os cupins, mas também em bioensaios com outros insetos de corpo mole.


Assuntos
Animais , Baratas , Isópteros , Bioensaio , Laboratórios
10.
Rev. colomb. ciencias quim. farm ; 51(3)set.-dez. 2022.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1535859

RESUMO

Introdução: perilartina é um adoçante natural potente, considerado 2000 vezes mais doce que o açúcar comum. Ela pode ser alérgica para algumas pessoas. Além disso, ela se usa apenas no Japão, o que pressupõe a possibilidade de adulterar produtos japoneses sem o seu uso. Assim, o desenvolvimento de um método eficiente da sua determinação qualificativa e quantificação é realmente atual. Metodologia: um modelo matemático de um processo anódico foi desenvolvido e analisado mediante a teoria de estabilidade linear e análise de bifurcações. O modelo inclui os cenários mais prováveis do andamento do processo eletroanalítico. Resultados: a perilartina é oxidada no meio básico, formando o poliol e o sal do "pseudoácido" correspondente, o que contribui fortemente para a força iônica da dupla camada elétrica. Isto pode ser responsável pela aparição das instabilidades oscilatória e monotônica no processo eletroanalítico. Conclusão: malgrado o supracitado, o compósito é um modificador eficiente para a determinação eletroquímica da perilartina no meio básico.


Introducción: perilartina es un edulcorante natural potente, considerado 2000 veces más dulce que el azúcar común. Esta puede causar alergia a algunas personas. Además, ella solo se usa en Japón, lo que presupone la posibilidad de falsificar productos japoneses sin su uso. Así, el desarrollo de un método eficiente de su determinación cuantitativa y cualitativa es realmente actual. Metodología: un modelo matemático de un proceso anódico fue desarrollado y analizado mediante la teoría de estabilidad lineal e análisis de bifurcaciones. El modelo incluye los escenarios más probables del curso del proceso electroanalítico. Resultados: la perilartinase oxida en el medio básico, formando el poliol y la sal del "pseudoácido" correspondiente, lo que contribuye fuertemente para la fuerza iónica de la doble capa eléctrica. Esto puede ser responsable por la aparición de las inestabilidades oscilatoria y monotónica en el proceso electroanalítico. Conclusión: a pesar de lo mencionado, el compuesto es un modificador eficaz para la determinación electroquímica de la perilartina en el medio básico.


SUMMARY Introduction: Perillartine is a strong natural sweetener, considered 2000 as sweet as a common sugar. It may be allergic to some people. Also, it is used only in Japan, which may presuppose the possibility of falsify Japanese products without its use. Thus the development of an eficiente method of its quantitative and qualitative determination is really actual. Methodology: A mathematical model of an anodic process has been developed and analyzed by means of linear stability theory and bifurcation analysis. The model includes the most probable scenarios of the course of the electroanalytical process. Results: Perillartine is oxidized in basic media, yielding the polyol and the correspondent pseudoacid salt, which strongly contributes to the double electric layer ionic force. This may be responsible for the oscillatory and monotonic instabilities appearance in the electroanalytical process. Conclusion: Despite of the above mentioned statements, the composite is na efficient modifier for the electrochemical determination of perillartine in basic media.

11.
Int. j. high dilution res ; 21(1): 24-24, May 6, 2022.
Artigo em Inglês | LILACS, HomeoIndex | ID: biblio-1396564

RESUMO

Under LPS-stimulus, platelets can activate macrophagesby a cell-to-cell contact or through cytokine degranulation. Rebound effects of anti-thrombotic agents, such as prostanoids and COX inhibitors can lead to thrombosis, infarct, and stroke. Aspirin has been prescribed for decades due to its powerful antiplatelet action, but it is also related to paradoxical effects such as withdrawal syndrome peaks, resistance, and thrombogenesis. Ultra-diluted aspirin can also produce the same effect in one hour, regardless of Cox-2, by still unknown pathways. Antithrombotic effects of aspirin are also reversed by its high dilutions.Aims: This study aims to characterize the effects of aspirin 15cH on macrophages challenged with LPS, a Cox-2 activator.Methodology: RAW 264.7 macrophages were sown in 24 wells plates using R10medium, boosted with 1µg/ml LPS,and treated with aspirin 15 cH and controls. The activity was evaluated after 24 hours. Supernatants were evaluated for cytokines, nitric oxide, and dielectric oscillations, through solvatochromic dyes (Cartwright's method).Results and discussion: macrophage spreading was increased by aspirin 15 cH, anLPS-like effect. Paradoxically, a significant reduction of this effect was noted when both, LPS and aspirin 15 cH, were added. Succussed water reversed the effect of LPS, leading to TNF (p<0.05) production close to baseline levels. Also, the single treatment with succussed water inhibited IL-10 production (p<0.05), but aspirin 200 µg/mL (positive control) highly increased it (p<0.0001), showing the validity of the model. Nitric oxide production was strengthened by LPS presence (p<0.0001), as expected, but partially downregulated after treatment with aspirin 200 µg/mL, water and succussed water. A pilot study with solvatochromic dyes showed no significant difference among treatments.Conclusion: The main data suggest that aspirin 15 cH increases macrophage activity but presents a paradoxal effect when mixed with LPS. On the other hand, succussed water itself has modulatory effects on macrophages.


Assuntos
Escalas de Preparação , Aspirina/uso terapêutico , Ativação de Macrófagos
12.
Int. j. high dilution res ; 21(1): 4-4, May 6, 2022.
Artigo em Inglês | LILACS, HomeoIndex | ID: biblio-1396607

RESUMO

Solvatochromic dyes are probes to detect variations on the dipole moment of solvents after the insertion of homeopathic potencies. Recent studies have shown they can be useful tools in laboratory and field studies to detect the activity of homeopathic remedies.Objective: Determine whether solvatochromic dyes can be a diagnostic tool for cells infected by different agents and/or markers to identify the activity of homeopathic medicines. Methods: Ethilicum1cH, Siliceaterra6, 30, 200cH; Zincummetallicum6, 30, 200cH and Phosphorus6, 30 and 200cH were analyzed by pouring the samples (in a 1:60 rate) into a series of seven dyes (rhodamine, ET 33, ET 30, coumarin 7, NN DMIA, Nile red, methylene violet) diluted in absolute ethanol using pre-established working concentrations. Oscillations of dye absorbance were observed at visible light spectrophotometry according to the remedy and potency. Water and succussed water were used as controls. In a second moment, the absorbance profile of the remedies will be compared with those of biological samples (supernatants) and checked with the biological effect previously obtained from each treatment.Supernatants of RAW 264.7 macrophages stimulated by Calmette-Guérin bacilli (BCG) or infected with Encephalitozoon cuniculiwill be analyzed. Results: Preliminary results have shown that Siliceaterra6cH, Phosphorus30 and 200cH and Zincummetallicum6, 30 and 200cH reduced the absorbance of methylene violet (p=0.01). Repetitions and analysis of supernatants are expected to be performed in the next steps of the study. Future perspectives: Establish a pattern of reactivity of the studied medicines with different dyes and the putative relation with the corresponding supernatants, as an attempt to obtain a "physicochemical signature" for each kind of infection and/or treatment.


Assuntos
Biomarcadores , Medicamento Homeopático , Corantes
13.
Braz. J. Pharm. Sci. (Online) ; 58: e20884, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1420383

RESUMO

Abstract Sunset yellow (SY), allura red (AR) and fast green (FG) are frequently used in commercial food products, although they are considered to be hazardous to public health due to their toxic efficacy and high exposure risk potency. In this study, a new, rapid, and reliable method based on a magnetic solid-phase extraction (MSPE) was developed for the simultaneous determination of SY, AR, and FG. Fe3O4 modified with Elaeagnus angustifolia was used for the first time as an adsorbent (Fe3O4-EA) in MSPE. It was characterized with scanning electron microscopy, Brunauer Emmet Teller surface area analysis and X-ray diffraction. MSPE parameters were optimized in terms of pH, adsorption, and elution time and elution volume. High-performance liquid chromatography was used for dye quantitation. Analytical separation was performed by applying ammonium acetate buffer, acetonitrile, and methanol as the mobile phase to a C18 reverse-phase analytical column. Intraday and inter-day repeatability of the method performed at the concentration of 0.2, 1.0 and 2.0 µg/mL exhibited <8.1% RSD (n=3). The limit of detection values was between 0.05-0.1 µg/mL. The adsorption data of SY, AR and FG on Fe3O4-EA were fitted with the Langmuir model with qmax values of 45.0, 70.4 and 73.0 mg/g, respectively.

14.
Malaysian Journal of Microbiology ; : 68-78, 2022.
Artigo em Inglês | WPRIM | ID: wpr-977454

RESUMO

Aims@#The present study investigated the biodegradation and removal of dye mixture (Remazol Brilliant Violet 5R and Reactive Red 120) using a new bacterial consortium isolated from dye-contaminated soil.@*Methodology and results@#Among the total 15 isolates screened, the two most efficient bacterial species (SS07 and SS09) were selected and identified as Enterobacter cloacae (MT573884) and Achromobacter pulmonis (MT573885). The removal efficiency of dye mixture by E. cloacae and A. pulmonis at an initial concentration of 100 mg/L was 82.78 and 84.96%, discretely. The bacterial consortium was developed using selected isolates and the optimum conditions for removing dyes were investigated. The maximum decolorization efficiency was achieved at pH 7; 35 °C; dye concentration, 100 mg/L; and initial inoculum concentration, 0.5 mL with mannitol and ammonium sulfate as carbon and nitrogen sources. The maximum removal efficiency of 91.3 ± 3.35% was achieved at the optimal conditions after 72 h of incubation.@*Conclusion, significance and impact of study@#Decolorization of azo dyestuff by the developed microbial consortia conforms to the zero-order reaction kinetics model. Consortia of E. cloacae and A. pulmonis was established as an effective decolorizer for the Remazol Brilliant violet 5R and Reactive Red 120 dye mixture with >90% color removal.


Assuntos
Compostos Azo , Consórcios Microbianos
15.
Rev. colomb. ciencias quim. farm ; 50(3)Sep.-Dec. 2021.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1535804

RESUMO

Introdução: a olanzapina é um dos fármacos antipsicóticos benzodiazepínicos mais usados no mundo. Apesar da sua eficiência, em concentrações excessivas, ela sói ser tóxica, como quaisquer outros fármacos desta classe. Assim, neste trabalho, se avaliou, pela primeira vez, a possibilidade da detecção eletroquímica do fármaco olanzapina, assistida pelo compósito do oxihidróxido de cobalto (III), emparelhado com o dióxido, com um corante esquaraínico. Método: o modelo matemático trivariante correspondente inclui dois cenários de oxidação do fármaco, possíveis para o caso, incluindo a eletropolimerização indireta da molécula da benzodiazepina condensada, bem como a oxidação do fármaco pelo átomo do enxofre. Este modelo tem sido desenvolvido e analisado mediante a teoria de estabilidade linear e análise de bifurcações. Resultados e discussão: a análise do modelo há mostrado que a hibridez do mecanismo do processo eletroanalítico, aliada à composição e descomposição dos compostos iônicos aquando da sua realização, aumenta a probabilidade da ocorrência do comportamento oscilatório, em relação ao caso mais simples e mais comum. No entretanto, a instabilidade oscilatória se realiza nos valores dos parâmetros, que estão além do limite de detecção. Por sua vez, o estado estacionário se obtém e se mantém facilmente, indicando um processo eletroanalítico eficiente, controlado pela difusão do analito. Conclusões: trata-se de um processo eletroanalítico eficiente, em que o composto de cobalto funciona como substância ativa, e o corante desempenha o papel de mediador


SUMMARY Introduction: olanzapine is one of the most used antipsychotic drugs in the world. Although it is efficient, it may be toxic in excess. Therefore, in this work the possibility of olanzapine electrochemical determination over an electrode, modified by the cobalt (III) oxyhydroxide in pair with its dioxide in a composite with squaraine dye. Methods: the trivariant correspondent mathematical model includes two scenarios of the drug oxidation, possible for the case, including the indirect electropolymerization of the condensed benzodiazepine molecule, like also its oxidation by sulfur atom. This model has been developed and analyzed by means of stability theory and bifurcation analysis. Results and discussion: the analysis of the model has shown that the mechanism hybridity of the electroanalytical process, alongside with the formation and decomposition of ionic compounds during its realization, augments the possibility for the oscillatory behavior realization, relatively to the simplest and commonest case. Nevertheless, the oscillatory instability is realized in parameter values far beyond the detection limit. On the other hand, the stable steady-state is easy to obtain and maintain, indicating an efficient electroanalytical process, controlled by the analyte diffusion. Conclusions: the electroanalytical process is efficient. The cobalt compound is acting as an active substance, and the dye is the mediator.


Introducción: la olanzapina es uno de los fármacos antipsicóticos más utilizados en el mundo. Aunque es eficaz, puede resultar tóxico en exceso. Por tanto, en este trabajo se plantea la posibilidad de la determinación electroquímica de olanzapina sobre un electrodo, modificado por el oxihidróxido de cobalto (III) en pareja con su dióxido en un composito con colorante de escuaraína. Métodos: el modelo matemático correspondiente incluye dos escenarios de oxidación del fármaco, posibles para el caso, que incluyen la electropolimerización indirecta de la molécula de benzodiazepina condensada, así como su oxidación por átomo de azufre. Este modelo ha sido desarrollado y analizado mediante teoría de estabilidad y análisis de bifurcación. Resultados y discusión: el análisis del modelo ha demostrado que el mecanismo de hibridación del proceso electroanalítico, junto con la formación y descomposición de compuestos iónicos durante su realización, aumenta la posibilidad de realización del comportamiento oscilatorio, relativamente al caso más simple y común. Sin embargo, la inestabilidad oscilatoria se realiza en valores de parámetros mucho más allá del límite de detección. Por otro lado, el estado estacionario estable es fácil de obtener y mantener, lo que indica un proceso electroanalítico eficiente, controlado por la difusión del analito. Conclusiones: el proceso electroanalítico es eficiente. El compuesto de cobalto actúa como sustancia activa y el colorante es el mediador.

16.
Eng. sanit. ambient ; 26(3): 485-494, maio-jun. 2021. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1286329

RESUMO

RESUMO O objetivo deste estudo foi caracterizar a produção de um carvão de caroço de pêssego e também avaliar a adsorção de corantes têxteis pelo carvão ativado de caroço de pêssego. A ativação do carvão foi realizada utilizando cloreto de zinco como agente oxidante. O carvão ativado foi então utilizado na adsorção de corantes, para posterior aplicação no tratamento de um efluente têxtil. Primeiramente, realizou-se a produção de carvão ativado com as temperaturas de 500, 700 e 900°C e tempo de carbonização de 10 15 e 20 minutos e verificou-se a remoção dos corantes preto reativo 5 e azul de metileno. De acordo com a metodologia de superfície de resposta, a melhor temperatura de produção apresentou-se acima de 700°C com tempo de exposição de 10 minutos para os dois corantes. Desse carvão ativado, avaliaram-se os dados de densidade, teor de umidade e cinzas, pH e rendimento. Também foram realizados ensaios cinéticos e de equilíbrio. Os dados foram ajustados a três modelos cinéticos. As medidas para determinação da eficiência na remoção de cor do efluente têxtil foram realizadas pelo método espectrofotométrico e demonstraram média de remoção superior a 62% da cor presente no efluente bruto. Desse modo, o caroço de pêssego demonstrou elevado potencial para a produção de carvão ativado visando o tratamento de efluentes contendo corantes, podendo servir como alternativa de baixo custo.


ABSTRACT The aim of this study was to characterize the production of activated charcoal from the peach kernel and assess the adsorption of textile dyes by this activated charcoal. The activation of the charcoal was performed using zinc chloride as the oxidizing agent. The activated charcoal was then used in the adsorption of dyes for later application in the treatment of a textile effluent. Firstly, the production of activated carbon was carried out at temperatures of 500, 700, and 900°C and carbonization time of 10, 15, and 20 minutes and the removal of the Reactive Black 5 and Methylene Blue dyes was verified. According to the methodology of response surface, the best production temperature was above 700°C with 10 min exposure for both dyes. From this activated carbon, data on density, moisture and ash content, pH, and yield were evaluated. Kinetic and equilibrium tests were also performed. The data were fitted to three kinetic models. The measures to determine the efficiency in the color removal of the textile effluent were carried out by the spectrophotometric method and demonstrated an average removal greater than 62% of the color present in the raw effluent. In this way, the peach kernel demonstrated a high potential for the production of activated carbon aiming at the treatment of effluents containing dyes and can serve as a low cost alternative.

17.
Rev. colomb. ciencias quim. farm ; 49(3): 699-709, Sep.-Dec. 2020. graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1156311

RESUMO

RESUMO O desempenho dos polímeros condutores dos corantes azoicos durante a detecção eletroquímica de indigo-carmim foi investigado do ponto de vista teórico, sendo o modelo, correspondente ao caso, descrito e analisado mediante a teoria de estabilidade lineal e da análise de bifiircações. Foi mostrado que o sistema eletroanalítico depende fortemente do pH, pois as concentrações excessivas dos prótons levam à ineficiência eletroanalítica, haja vista o bloqueio dos centros ativos da reação. No entretanto, malgrado o supracitado, os polímeros dos corantes azoicos são modificadores eficientes para determinação do indigo-carmim. A possibilidade das instabilidades oscilatória e monotônica também foi verificada.


SUMMARY The function of the conducting polymers of azo-dyes during the indigo-carmine electrochemical detection has been investigated from the theoretical point of view. The correspondent model has been described and analyzed by means of linear stability theory and bifurcation analysis. It has been shown that the electroanalytical system depends strongly on pH, as the excessive protons concentrations drive the system to the electroanalytical inefficiency, as they block the reaction active sites. Nevertheless, despite of the mentioned, the azo-dyes conducting polymers are efficient modifiers for indigo-carmine electrochemical determination. The possibility of oscillatory and monotonic instabilities has also been verified.

18.
Electron. j. biotechnol ; 46: 22-29, jul. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1223226

RESUMO

BACKGROUND: Removal of dyes from wastewater by microorganisms through adsorption, degradation, or accumulation has been investigated. Biological methods used for dye treatment are generally always effective and environmentally friendly. In this study, biosorption of the Fast Black K salt azo dye by the bacterium Rhodopseudomonas palustris 51ATA was studied spectrophotometrically, at various pH (2­10), temperatures (25°C, 35°C, and 45°C) and dye concentrations (25­400 mg L-1). RESULTS: The bacterial strain showed extremely good dye-removing potential at various dye concentrations. IR studies at different temperatures showed that the dye was adsorbed on the bacterial surface at lower temperatures. Characteristics of the adsorption process were investigated by Scatchard analysis at 25°C and 35°C. Scatchard analysis of the equilibrium binding data for the dye on this bacterium gave rise to linear plots, indicating that the Langmuir model could be applied. The regression coefficients obtained for the dye from the Freundlich and Langmuir models were significant and divergence from the Scatchard plot was observed. CONCLUSION: The adsorption behavior of the dye on this bacterium was expressed by the Langmuir, Freundlich, and Temkin isotherms. The adsorption data with respect to various temperatures provided an excellent fit to the Freundlich isotherm. However, when the Langmuir and Temkin isotherm models were applied to these data, a good fit was only obtained for the dye at lower temperatures, thus indicating that the biosorption ability of R. palustris 51ATA is dependent on temperature, pH, and dye concentration.


Assuntos
Rodopseudomonas/metabolismo , Compostos de Diazônio/metabolismo , Corantes/metabolismo , Temperatura , Compostos Azo/análise , Compostos Azo/metabolismo , Remoção de Contaminantes , Adsorção , Corantes/análise , Águas Residuárias , Concentração de Íons de Hidrogênio
19.
An. bras. dermatol ; 95(3): 332-335, May-June 2020. graf
Artigo em Inglês | LILACS, ColecionaSUS | ID: biblio-1130874

RESUMO

Abstract Tinea capitis comprising of tinea favosa and kerion is mostly seen in school-aged children. Some tinea capitis often presented with insignificant findings under the naked eyes are easily overlooked. The authors describe an unusual case of tinea capitis caused by Trichophyton violaceum. The patient was an 8-year-old girl, with a history of pruritus on the scalp for more than one year. A diagnosis of tinea capitis was confirmed by clinical examination aided by dermoscopy, calcium fluorescent microscopy and culture. Comma and corkscrew hairs are two specific dermoscopic patterns of tinea capitis. The patient was treated with systemic itraconazole, topical application with 1% naftifine 0.25% ketoconazole cream followed after daily hair wash with 2% ketoconazole shampoo for 8 weeks.


Assuntos
Humanos , Feminino , Criança , Tinha do Couro Cabeludo/diagnóstico por imagem , Cálcio , Microscopia de Fluorescência/métodos , Tinha do Couro Cabeludo/patologia , Trichophyton/isolamento & purificação , Reprodutibilidade dos Testes , Dermoscopia/métodos
20.
Eng. sanit. ambient ; 25(2): 361-369, mar.-abr. 2020. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1098206

RESUMO

RESUMO As leveduras vêm apresentando bons resultados na biodegradação de corantes, tornando-se uma alternativa ambientalmente segura e de custo mais baixo para o tratamento de efluentes contendo corantes industriais. Assim, o objetivo deste trabalho foi estudar a descoloração do azo corante Preto Reativo 5 (PR5) pela levedura Pichia kudriavzevii SD5. Para otimização dos parâmetros de descoloração do Preto Reativo 5 foram realizados dois planejamentos experimentais do tipo Delineamento Composto Central Rotacional (DCCR) 23, sendo cada planejamento composto por 17 ensaios, a 150 rpm durante 24 h. As variáveis estudadas foram pH, temperatura e concentração do corante e tiveram como resposta a porcentagem de descoloração. Também foram realizados testes de toxicidade do sobrenadante após 16 h e 24 h de cultivo, utilizando-se sementes de alface (Lactuca sativa) e o microcrustáceo Artemia salina. Os resultados mostraram que a P. kudriavzevii SD5 é uma levedura tolerante a vários tipos de estresse, uma vez que apresentou capacidade de degradar elevadas concentrações do corante PR5 a 45° C. Entretanto, apenas a temperatura apresentou influência estatisticamente significativa (p < 0,05) na descoloração do PR5. Os bioensaios de toxicidade demonstraram que ocorreu diminuição da toxicidade após 24 h de cultivo, e o perfil de absorbância do sobrenadante apontou para um mecanismo degradativo de descoloração.


ABSTRACT Yeasts have been showing good results in the biodegradation of industrial dyes, becoming an environmentally safe and cost-effective alternative for the treatment of effluents containing industrial dyes. Thus, the objective of this work was to study the discoloration of the Reactive Black 5 (RB5) azo dye by the yeast Pichia kudriavzevii SD5. Two experimental designs were employed to optimize the discoloration parameters by means of Central Composite Design (CCD) 23, totalizing 17 trials each, at 150 rpm for 24 h. The studied independent variables were pH, temperature, and concentration of the dye and the outcome parameter was the rate of decolorization (%). Furthermore, the toxicity bioassays of the supernatant after 16 and 24 h of the culture were carried out using lettuce seeds (Lactuca sativa) and the microcrustacean Artemia salina. Results showed that P. kudriavzevii SD5 is a multi-stress tolerant yeast, being capable to degrade high concentrations of RB5 at 45° C. However, only the temperature showed statistical significance (p < 0.05) for dye discoloration. Toxicity bioassays demonstrated that toxicity decreased after 24 h of culture and the absorbance profile of the supernatant pointed to a degradative mechanism of discoloration.

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