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1.
Braz. j. biol ; 84: e252364, 2024. graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1355885

ABSTRACT

Abstract Understanding morphological and physiological changes under different light conditions in native fruit species in juveniles' stage is important, as it indicate the appropriate environment to achieve vigorous saplings. We aimed to verify growth and morphophysiological changes under shade gradient in feijoa (Acca sellowiana (O. Berg) Burret) to achieve good quality saplings adequate to improve cultivation in orchards. The saplings were grown for twenty-one-month under four shading treatments (0%, 30%, 50%, and 80%). Growth, photosynthetic pigments, gas exchanges, chlorophyll fluorescence, and leaf anatomy parameters were evaluated. Saplings under full sun and 30% shade had higher height and diameter growth and dry mass accumulation due to higher photosynthesis rate. As main acclimatization mechanisms in feijoa saplings under 80% shade were developed larger leaf area, reduced leaf blade thickness, and enhanced quantum yield of photosystem II. Even so, the net CO2 assimilation and the electron transport rate was lower and, consequently, there was a restriction on the growth and dry mass in saplings under deep shade. Therefore, to obtain higher quality feijoa saplings, we recommend that it be carried out in full sun or up to 30% shade, to maximize the sapling vigor in nurseries and, later, this light environment can also be used in orchards for favor growth and fruit production.


Resumo A verificação de mudanças morfológicas e fisiológicas sob diferentes condições luminosas em espécies frutíferas nativas em estágio juvenil é importante, uma vez que indicam o ambiente adequado para a formação de mudas com alto vigor. Objetivou-se verificar o crescimento e as alterações morfofisiológicas sob gradiente de sombreamento em mudas de feijoa (Acca sellowiana (O. Berg) Burret) para obter mudas de boa qualidade, adequadas para fomentar os plantios da espécie em pomares. As mudas foram cultivadas por vinte e um meses sob quatro tratamentos de sombreamento (0%, 30%, 50% e 80%). Foram avaliados parâmetros de crescimento, pigmentos fotossintéticos, trocas gasosas, fluorescência da clorofila e anatomia foliar. Mudas a pleno sol e 30% de sombra apresentaram maior crescimento em altura, diâmetro e acúmulo de massa seca, devido à maior taxa de fotossíntese. Como principais mecanismos de aclimatação sob 80% de sombra, as mudas desenvolveram maior área foliar, redução da espessura do limbo foliar e aumento do rendimento quântico do fotossistema II. Mesmo assim, a assimilação líquida de CO2 e a taxa de transporte de elétrons foram menores e, consequentemente, houve restrição ao crescimento e acúmulo de massa seca das mudas no maior nível de sombreamento. Portanto, para a obtenção de mudas de feijoa de maior qualidade, recomendamos que seja realizada a pleno sol ou até 30% de sombra, para maximizar o vigor das mudas em viveiros e, posteriormente, este ambiente de luz também pode ser utilizado em pomares para favorecer o crescimento e a produção de frutos.


Subject(s)
Myrtaceae , Feijoa , Photosynthesis , Plant Leaves , Acclimatization , Light
2.
Braz. j. biol ; 82: e231742, 2022. graf
Article in English | LILACS | ID: biblio-1153476

ABSTRACT

Abstract The ability of pathogenic bacteria acquire resistance to the existing antibiotics has long been considered a dangerous health risk threat. Currently, the use of visible light has been considered a new approach to treat bacterial infections as an alternative to antibiotics. Herein, we investigated the antimicrobial effect of two range of visible light, blue and red, on Staphylococcus aureus and Pseudomonas aeruginosa, two pathogenic bacterial commonly found in healthcare settings-acquired infections and responsible for high rate of morbidity and mortality. Bacterial cultures were exposed to blue or red light (470 nm and 660 nm) provided by light-emitting diodes - LED. The fluencies and irradiance used for blue and red light were 284.90 J/cm2, 13.19 mW/cm2 and 603.44 J/cm2, 27.93 mW/cm2 respectively. Different experimental approaches were used to determine the optimal conditions of light application. Only exposure to blue light for 6 hours was able to inhibit about 75% in vitro growth of both bacterial species after 24 hours. The surviving exposed bacteria formed colonies significantly smaller than controls, however, these bacteria were able to resume growth after 48 hours. Blue light was able to inhibit bacterial growth upon inoculation in both saline solution and BHI culture medium. We can conclude that blue light, but not red light, is capable of temporarily retarding the growth of gram negative and gram positive bacteria.


Resumo A capacidade das bactérias patogênicas adquirirem resistência aos antibióticos existentes há muito tempo é considerada uma ameaça perigosa à saúde. Atualmente, o uso da luz visível tem sido considerado uma nova abordagem no tratamento de infecções bacterianas como alternativa aos antibióticos. Neste trabalho, investigamos o efeito antimicrobiano de duas faixas de luz visível, azul e vermelha, em Staphylococcus aureus e Pseudomonas aeruginosa, duas bactérias patogênicas comumente encontradas em infecções adquiridas em instituições de saúde e responsáveis por alta taxa de morbimortalidade. As culturas bacterianas foram expostas à luz azul ou vermelha (470 nm e 660 nm) fornecida por diodos emissores de luz - LED. As fluências e irradiâncias utilizadas para luz azul e vermelha foram 284,90 J/cm2, 13,19 mW/cm2 e 603,44 J/cm2, 27,93 mW/cm2, respectivamente. Várias abordagens experimentais foram utilizadas para determinar as condições ótimas de aplicação da luz. Apenas a exposição à luz azul por 6 horas foi capaz de inibir cerca de 75% o crescimento in vitro de ambas as espécies bacterianas após 24 horas. As bactérias expostas sobreviventes formaram colônias com um tamanho significativamente menor do que os controles, contudo, essas bactérias conseguiram retomar o crescimento normal após 48 horas. A luz azul foi capaz de inibir o crescimento das bactérias após sua inoculação em solução salina ou no meio de cultura rico em nutrientes BHI. Podemos concluir que a luz azul mas não a luz vermelha é capaz de retardar temporariamente o crescimento de bactérias Gram-negativas e Gram-positivas.


Subject(s)
Humans , Staphylococcal Infections , Staphylococcus aureus , Pseudomonas aeruginosa , Light , Anti-Bacterial Agents
3.
Electron. j. biotechnol ; 51: 50-57, May. 2021. ilus, graf
Article in English | LILACS | ID: biblio-1343384

ABSTRACT

BACKGROUND: Molecular brain therapies require the development of molecular switches to control gene expression in a limited and regulated manner in time and space. Light-switchable gene systems allow precise control of gene expression with an enhanced spatio-temporal resolution compared to chemical inducers. In this work, we adapted the existing light-switchable Light-On system into a lentiviral platform, which consists of two modules: (i) one for the expression of the blue light-switchable transactivator GAVPO and (ii) a second module containing an inducible-UAS promoter (UAS) modulated by a light-activated GAVPO. RESULTS: In the HEK293-T cell line transfected with this lentiviral plasmids system, the expression of the reporter mCherry increased between 4 to 5 fold after light induction. A time expression analysis after light induction during 24 h revealed that mRNA levels continuously increased up to 9 h, while protein levels increased throughout the experiment. Finally, transduction of cultured rat hippocampal neurons with this dual Light-On lentiviral system showed that CDNF, a potential therapeutic trophic factor, was induced only in cells exposed to blue light. CONCLUSIONS: In conclusion, the optimized lentiviral platform of the Light-On system provides an efficient way to control gene expression in neurons, suggesting that this platform could potentially be used in biomedical and neuroscience research, and eventually in brain therapies for neurodegenerative diseases.


Subject(s)
Gene Expression Regulation , Optogenetics/methods , Light , Neurons/metabolism , Immunoblotting , Gene Expression , Fluorescent Antibody Technique , Lentivirus
4.
Rev. ADM ; 78(2): 73-79, mar.-abr. 2021. ilus, tab
Article in Spanish | LILACS | ID: biblio-1247336

ABSTRACT

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)


Subject(s)
Humans , Tooth Discoloration , Beverages , Color , Colorimetry , Esthetics, Dental , Spectrophotometry/methods , Wine , In Vitro Techniques , Epidemiology, Descriptive , Statistical Analysis , Coffee , Juices , Light
5.
Article in Chinese | WPRIM | ID: wpr-888627

ABSTRACT

The uniformity of blue LED array in jaundice treatment box is improved. The mathematical model of illumination uniformity algorithm for inner and outer LED arrays layout is established. Taking the actual size of blue light board in jaundice treatment box as an example, the optimal illumination uniformity with best LED arrays layout are obtained through programming iteration and simulation verification. The uniformity of blue light LED improved 42.9 % comparing with tradition LED arrays.


Subject(s)
Computer Simulation , Humans , Jaundice , Light , Lighting
7.
Psicol. ciênc. prof ; 40: e189510, jan.-maio 2020.
Article in Portuguese | LILACS, INDEXPSI | ID: biblio-1140926

ABSTRACT

O romance Mrs. Dalloway, escrito pela inglesa Virginia Woolf (1882-1941), é um marco na literatura universal por apresentar um novo formato na arte da escrita intitulado fluxo de consciência. Esta forma estilística visa descrever as falas e os pensamentos dos personagens por meio do discurso indireto livre, integrado à preleção do narrador. O enredo se passa em um único dia da vida da protagonista Clarissa Dalloway, no qual são captados os ínfimos detalhes do que ela experiencia. Dentre os fenômenos vivenciados encontramos a noção de tempo, por meio da qual o narrador mistura homogeneamente o fluxo passado, presente e futuro. O objetivo deste artigo é discutir a vivência do tempo na referida obra literária pautada numa discussão fenomenológica. Para isto, utilizamos como método a revisão narrativa da literatura de autores que contribuíram para o desenvolvimento da noção de tempo vivido na fenomenologia. É no fluxo do tempo que se dão os significados das experiências na história dos personagens no seu contato ambíguo com o mundo. Concluímos que as descrições elaboradas por Virginia Woolf possibilitam uma aproximação à vivência do tempo, que atravessa a totalidade da dimensão do ser...(AU)


The novel Mrs. Dalloway, written by English writer Virginia Woolf (1882-1941), is a landmark in universal literature for presenting a new format in the art of writing named Stream of Consciousness. This stylistic form aims to describe the speeches and thoughts of the characters through free indirect speech, integrated to the narrator's lecture. The novel takes place in a single day of the life of the protagonist Clarissa Dalloway, capturing the minute details of what she experiences. Among the phenomena experienced we find the notion of time, whereby the narrator mixes the past, present, and future flux into one envelope. This article thus discusses the experience of time in this literary work based on a phenomenological discussion. We conducted a review of the literature including authors that contributed to the development of the notion of experienced time in phenomenology. In the flow of time lie meanings of the experiences of characters in their ambiguous contact with the world. We conclude that the descriptions elaborated by Virginia Woolf allow for an approximation to the experience of time that crosses the totality of the dimension of being...(AU)


La novela La Señora Dalloway, de la escritora inglesa Virginia Woolf (1882-1941), es un hito en la literatura universal por presentar un nuevo formato en el arte de la escritura titulado "flujo de conciencia". Esta forma estilística pretende describir las palabras y los pensamientos de los personajes por medio del discurso indirecto libre, integrado a la prelección del narrador. La historia de la novela se pasa en un único día de la vida de la protagonista Clarissa Dalloway, en el que se captan los ínfimos detalles de lo que ella experimenta. Entre los fenómenos vivenciados encontramos la noción de tiempo, por medio de la cual el narrador mezcla el flujo pasado, presente y futuro en un envoltorio único. El objetivo de este artículo es discutir la vivencia del tiempo en la referida obra literaria pautada en una discusión fenomenológica. Para ello, utilizamos como método la revisión de la literatura de autores que contribuyeron al desarrollo de la noción de tiempo vivido en la fenomenología. Es en el flujo del tiempo que se dan los significados de las experiencias en la historia de los personajes en su contacto ambiguo con el mundo. Concluimos que las descripciones elaboradas por Virginia Woolf posibilitan una aproximación a la vivencia del tiempo, que atraviesa la totalidad de la dimensión del ser...(AU)


Subject(s)
Humans , Female , Adult , Thinking , Time , Life , Narration , Famous Persons , History , Literature , Speech , Work , Writing , Consciousness , Growth and Development , Forecasting , Light
8.
Biosci. j. (Online) ; 36(3): 924-931, 01-05-2020. tab
Article in English | LILACS | ID: biblio-1146988

ABSTRACT

Fungi are capable of sensing light from ultraviolet to far-red and they use light as a source of information about the environment anticipating stress and adverse conditions. Lentinus crinitus is a lignin-degrading fungus which produces laccase and other enzymes of biotechnological interest. The effect of blue light on fungal enzymatic activity has been studied; however, it has not been found studies on the effect of the blue light on carbohydrate-active enzymes and on mycelial biomass production of L. crinitus. We aimed to investigate carbohydrate-active enzymes activity and mycelial biomass production of L. crinitus cultivated under continuous illumination with blue light. L. crinitus was cultivated in malt extract medium in the dark, without agitation, and under continuous illumination with blue light-emitting diodes. The blue light reduced the total cellulase, pectinase and xylanase activities but increased the endoglucanase activity. Blue light reduced the mycelial growth of L. crinitus in 26% and the enzymatic activity-to-mycelial biomass ratio (U mg-1 dry basis) increased in 10% total cellulase, 33% endoglucanase, and 16% pectinase activities. Also, it is suggested that L. crinitus has a photosensory system and it could lead to new process of obtaining enzymes of biotechnological interest.


Fungos são capazes de sentir a luz com comprimentos de onda que variam do ultravioleta ao infravermelho e usam a luz como fonte de informação sobre o ambiente, antecipando condições adversas e de estresse. Lentinus crinitus é um fungo ligninolítico que produz lacase e outras enzimas de interesse biotecnológico. O efeito da luz azul na atividade enzimática de fungos já foi estudado, contudo, ainda não há estudos sobre o efeito da luz azul na produção de enzimas ativas sobre carboidratos (CAZymes, carbohydrate-active enzymes) e de biomassa micelial de L. crinitus. O objetivo deste estudo foi investigar a avitivade de CAZymes e a produção de biomassa micelial de L. crinitus cultivado sob iluminação continua com luz azul. L. crinitus foi cultivado em meio extrato de malte, sem agitação, na ausência de luz e sob luz continua fornecida por diodos emissores de luz azul. A luz azul reduziu a atividade de cellulase total, pectinase e xilanase, mas aumentou a atividade de endoglucanase. A luz azul reduziu o crescimento micelial de L. crinitus em 26% e aumentou a razão atividade enzimática/biomassa micelial (U mg-1 em base seca) de cellulase total em 10%, endoglucanase em 33% e pectinase em 16%. Além disso, sugere-se que L. crinitus possua um sistema fotossensorial que poderia ser explorado para a otimização de bioprocessos que visam a obtenção de enzimas de interesse biotecnológico.


Subject(s)
Polygalacturonase , Lentinula , Cellulases , Light
9.
Electron. j. biotechnol ; 44: 14-18, Mar. 2020. ilus, graf
Article in English | LILACS | ID: biblio-1087629

ABSTRACT

BACKGROUND: Although bioactive metabolites capable of causing oxidative photo-necrosis in plant tissues have been identified in fungi, little is known about this type of mechanism in bacteria. These metabolites act as photosensitizers that generate reactive oxygen species (ROS) capable of causing damage to cells. In addition, these metabolites can pass into an energetically excited state when they receive some luminous stimulus, a condition in which they interact with other molecules present in the environment, such as molecular oxygen (O2), also known as triplet oxygen (3 O2), generating ROS. RESULTS: The suspension of the bacterial culture of Pseudomonas cedrina was shown to produce foliar necrosis in papaya leaves (Carica papaya L.) only in the presence of sunlight, which is evidence of photosensitizing mechanisms that generate singlet oxygen (1 O2). From the chemical study of extracts obtained from this bacteria, 3-(4-(2-carboxipropyl) phenyl) but-2-enoic acid (1) was isolated. This compound, in the presence of light and triplet oxygen (3 O2), was able to oxidize ergosterol to its peroxide, since it acted as a photosensitizer producing 1 O2, with which it was corroborated that a photosensitization reaction occurs, mechanism by which this bacterium could prove to cause oxidative foliar photo-necrosis. CONCLUSIONS: P. cedrina was able to induce oxidative foliar photo-necrosis because of its potential ability to produce photosensitizing metabolites that generate singlet oxygen in the plants it colonizes. Based on the above, it can be proposed that some bacteria can cause oxidative foliar photo-necrosis as an important mechanism in the pathogenesis of host species.


Subject(s)
Plant Diseases/microbiology , Pseudomonas/physiology , Carica/microbiology , Singlet Oxygen/metabolism , Pseudomonas/metabolism , Acids , Reactive Oxygen Species , Plant Leaves/microbiology , Photooxidation , Light , Necrosis
10.
An. bras. dermatol ; 95(1): 46-51, Jan.-Feb. 2020. graf
Article in English | LILACS | ID: biblio-1088734

ABSTRACT

Abstract Background: Organoid cultures are primary cultures that maintain architectural characteristics and the relationships between cells, as well as the extracellular matrix. They are alternatives for pathophysiological or therapeutic investigation rather than animal and in vitro tests. Objective: Development of a cutaneous organoid culture model, aiming at the study of radiation-induced melanogenesis. Method: A validation study, which involved biopsies of the skin of the back of the adult ear. One sample was irradiated with different doses of UVB, UVA, or visible light (VL); the other was maintained in the dark for 72 h. The viability of the tissues was evaluated from the morphological and architectural parameters of the histology, and the expression of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene, by real-time polymerase chain reaction (PCR). The radiation-induced melanin pigmentation was standardized according to the doses of each radiation and evaluated by digital image analysis (Fontana-Masson). Results: The primary skin culture was standardized at room temperature using DMEM medium. The doses of UVB, UVA, and VL (blue light) that induced differential melanogenesis were: 166 mJ/cm2, 1.524 J/cm2, and 40 J/cm2. The expression of the GAPHD constitutional gene did not differ between the sample of skin processed immediately after tissue collection and the sample cultured for 72 h in the standardized protocol. Study limitations: This was a preliminary study that evaluated only the viability and integrity of the melanogenic system, and the effect of the radiation alone. Conclusions: The standardized model maintained viable melanocytic function for 72 h at room temperature, allowing the investigation of melanogenesis induced by different forms of radiation.


Subject(s)
Humans , Adult , Ultraviolet Rays , Organoids/radiation effects , Cell Culture Techniques/standards , Light , Melanins/biosynthesis , Melanins/radiation effects , Radiation Dosage , Silver Nitrate , Time Factors , Biopsy , Skin Pigmentation/radiation effects , Gene Expression , Cells, Cultured , Reproducibility of Results , Real-Time Polymerase Chain Reaction
12.
Biosci. j. (Online) ; 36(1): 68-77, jan./feb. 2020. graf
Article in English | LILACS | ID: biblio-1049197

ABSTRACT

H. impetiginosus belongs to the Bignoniaceae family; it has a great potential for economic exploitation and can be used in landscaping of urban areas, reforestation, recovery of degraded areas, and folk medicine. The experiment was carried out to evaluate the effect of light and temperature regimes on the germination and vigor of Handroanthus impetiginosus seeds at the Seed Analysis Laboratory of UFRPE/UAG. The seeds were subjected to light regimes: white, far red, red, and no light at 15°C, 20°C, 25°C, 30°C, 35°C, and 40°C, using a completely randomized experimental design in a factorial scheme (4 × 6), with four repetitions of 25 seeds. The different light regimes did not influence the seed germination of H. impetiginosus. The highest germination percentage (92%) and germination speed index (7.94) were obtained at temperatures 28.2°C and 29.2°C, respectively, both under red light. The longest seedling length was also obtained from the seeds subjected to red light regime at 25°C. The temperatures of 15°C and 40°C inhibited the germination of H. impetiginosus seeds. H. impetiginosus seeds are classified as neutral photoblastics, and constant temperatures of 28.2°C and 29.2°C provided maximum germination.


H. impetiginosus, pertencente à família Bignoniaceae, apresenta grande potencial para exploração econômica, podendo ser utilizado no paisagismo de áreas urbanas, reflorestamentos, recuperação de áreas degradadas e na medicina popular. O experimento foi conduzido no Laboratório de Análise de Sementes da UFRPE/UAG com o objetivo de avaliar o efeito dos regimes de luz e temperatura na germinação e vigor de sementes de Handroanthus impetiginosus. As sementes foram submetidas aos regimes de luz: branca, vermelho distante, vermelho e ausência de luz sob as temperaturas de 15, 20, 25, 30, 35 e 40°C, sendo utilizado o delineamento experimental inteiramente ao acaso, em esquema fatorial (4x6), com quatro repetições de 25 sementes. Os diferentes regimes de luz não influenciaram na germinação de sementes de H.impetiginosus. A maior porcentagem de germinação (92%) e índice de velocidade de germinação (7,94) foram obtidos nas temperaturas 28,2 e 29,2°C, respectivamente, ambos no regime de luz vermelha. O maior comprimento de plântula também foi obtido de sementes submetidas ao regime de luz vermelha na temperatura de 25ºC. As temperaturas de 15ºC e 40ºC inibiram a germinação das sementes de H. impetiginosus. As sementes de H. impetiginosus são classificadas como fotoblásticas neutras e as temperaturas constantes de 28,2 e 29,2°C proporcionaram máxima germinação.


Subject(s)
Seeds , Temperature , Germination , Tabebuia , Light
13.
J. appl. oral sci ; 28: e20190720, 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1134776

ABSTRACT

Abstract Objective This study evaluated the clinical effect of violet LED light on in-office bleaching used alone or combined with 37% carbamide peroxide (CP) or 35% hydrogen peroxide (HP). Methodology A total of 100 patients were divided into five groups (n=20): LED, LED/CP, CP, LED/HP and HP. Colorimetric evaluation was performed using a spectrophotometer (ΔE, ΔL, Δa, Δb) and a visual shade guide (ΔSGU). Calcium (Ca)/phosphorous (P) ratio was quantified in the enamel microbiopsies. Measurements were performed at baseline (T 0 ), after bleaching (T B ) and in the 14-day follow-up (T 14 ). At each bleaching session, a visual scale determined the absolute risk (AR) and intensity of tooth sensitivity (TS). Data were evaluated by one-way (ΔE, Δa, ΔL, Δb), two-way repeated measures ANOVA (Ca/P ratio), and Tukey post-hoc tests. ΔSGU and TS were evaluated by Kruskal-Wallis and Mann-Whitney, and AR by Chi-Squared tests (a=5%). Results LED produced the lowest ΔE (p<0.05), but LED/HP promoted greater ΔE, ΔSGU and Δb (T 14 ) than HP (p<0.05). No differences were observed in ΔE and ΔSGU for LED/CP and HP groups (p>0.05). ΔL and Δa were not influenced by LED activation. After bleaching, LED/CP exhibited greater Δb than CP (p>0.05), but no differences were found between these groups at T 14 (p>0.05). LED treatment promoted the lowest risk of TS (16%), while HP promoted the highest (94.4%) (p<0.05). No statistical differences of risk of TS were found for CP (44%), LED/CP (61%) and LED/HP (88%) groups (p>0.05). No differences were found in enamel Ca/P ratio among treatments, regardless of evaluation times. Conclusions Violet LED alone produced the lowest bleaching effect, but enhanced HP bleaching results. Patients treated with LED/CP reached the same efficacy of HP, with reduced risk and intensity of tooth sensitivity and none of the bleaching protocols adversely affected enamel mineral content.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Phototherapy/methods , Tooth Bleaching/methods , Tooth Bleaching Agents/administration & dosage , Carbamide Peroxide/administration & dosage , Hydrogen Peroxide/administration & dosage , Light , Reference Values , Spectrophotometry , Surface Properties/drug effects , Surface Properties/radiation effects , Risk Factors , Analysis of Variance , Treatment Outcome , Colorimetry , Combined Modality Therapy , Statistics, Nonparametric , Dental Enamel/drug effects , Dental Enamel/radiation effects , Dentin Sensitivity/chemically induced
14.
Rev. Ciênc. Plur ; 6(2): 101-112, 2020. tab
Article in Portuguese | LILACS, BBO | ID: biblio-1100314

ABSTRACT

Introdução:Oclareamento dental é o procedimento estético mais realizado nos consultórios odontológicos. O uso de fontes luminosas tem sido recomendado para acelerar a ação do gel clareador, entretanto evidências científicas são controversas no que se diz respeito a essas fontes.Objetivo:Avaliar protocolos de clareamento dentário modificados por fontes luminosas, objetivando verificar, qual a influência dessas fontes no procedimento de clareamento dentário.Metodologia:Sendo essa, uma pesquisa que utilizou material biológico, a mesma foi submetida e aprovada pelo Comitê de Ética em Pesquisa da UEPB. Realizou-se a obtenção de dentes(n = 20)por meio de parceria com o Banco de Dentes Humanos do curso de Odontologia da UEPB Campus VIII. Posteriormente realizou-se identificação dos dentes, em seguida registro inicial da cor do dente(escala VITA), o preparo dos blocos dentários e seleção dos grupos. Os dentes foram submetidos a dois protocolos de clareamentos distintos, com luz halógena e com LED, com ou sem troca do gel. Por fim, realizada a análise estatística. Resultados:A modificação do protocolo, seja quanto o tempo de aplicação do agente clareador, seja quanto à fonte de luz utilizada, alcança resultados satisfatórios. Houve diferença estatisticamente significativa entre os gruposda luz halógena (p = 0.041)Conclusões:Tendo em vista os resultados e a discussão encontrados na pesquisa, podemos verificar que as evidências científicas nos levam a observar que não há bases suficientes que comprovem a eficácia e benefícios a curto prazo da modificação dos protocolos de clareamento dental pelas fontes luminosas (AU).


Introduction:Tooth whitening is the most common cosmetic procedure performed in dental offices. The use of light sources has been recommended to accelerate the action of the whitening gel;however scientific evidence is controversial regardingthese sources.Objective:Evaluate tooth whitening protocols modified by light sources, aiming to verify, what is the influence of these sources in the tooth whitening procedure. Methodology:This being a research that used biological material, it was submitted and approved by theResearch Ethics Committee of UEPB. Teeth (n = 20) were obtained through a partnership with the Human Teeth Bank of the Dentistry course at UEPB Campus VIII. Subsequently, teeth identification was performed, followed by initial registration of tooth color(VITA scale), preparation of dental blocks and selection of groups. The teeth were submitted to two different whitening protocols, with halogen light and with LED, with or without changing the gel. Finally, statistical analysis was performed. Results:Themodification of the protocol, both in terms of the application time of the bleaching agent and in terms of the light source used, achieves satisfactory results. There was statistically significant difference between groupswith halogen light (p = 0.041). Conclusions:In view of the results and the discussion found in the research, we can see that the scientific evidence leads us to observe that there are not enough bases to prove the effectiveness and short-term benefits of modifying the teeth whitening protocols by light sources (AU).


Introducción: El blanqueamiento dental es el procedimiento cosmético más común que se realiza en consultorios dentales. Se ha recomendado el uso de fuentesde luz para acelerar la acción del gel blanqueador, sin embargo, la evidencia científica es controvertida con respecto a estas fuentes.Objetivo: Evaluar los protocolos de blanqueamiento dental modificados por fuentes de luz, con el objetivo de verificar cuál es la influencia de estas fuentes en el procedimiento de blanqueamiento dental. Metodología: Al tratarse de una investigación que utilizó material biológico, fue presentada y aprobada por el Comité de Ética en Investigación de la UEPB. Los dientes (n = 20) se obtuvieron a través de una asociación con el Banco de Dientes Humanos del curso de Odontología en el Campus VIII de la UEPB. Posteriormente, se realizó la identificación de los dientes, seguida del registro inicial del color del diente(escala VITA), la preparación de los bloques dentales y la selección de grupos. Los dientes fueron sometidos a dos protocolos diferentes de blanqueamiento, con luz halógena y con LED, con o sin cambiar el gel. Finalmente, se realizó un análisis estadístico. Resultados: La modificación del protocolo, tanto en términos del tiempo de aplicación del agente blanqueador como en términos de la fuente de luz utilizada, logra resultados satisfactorios. Hubo diferencias estadísticamente significativas entre los gruposcom luz halógena (p =0.041).Conclusiones: En vista de los resultados y la discusión encontrada en la investigación, podemos ver que la evidencia científica nos lleva a observar que no hay suficientes bases para probar la efectividad y los beneficios a corto plazo de modificar los protocolos de blanqueamiento dental por fuentes de luz (AU).


Subject(s)
Humans , Tooth Bleaching/methods , Clinical Protocols , Hydrogen Peroxide , Lasers , Light , Brazil , Statistics, Nonparametric , Molar
15.
Chinese Journal of Biotechnology ; (12): 2126-2138, 2020.
Article in Chinese | WPRIM | ID: wpr-878472

ABSTRACT

Development of "liquid sunshine" could be a key technology to deal with the issue of fossil fuel depletion. β-caryophyllene is a terpene compound with high energy density and has attracted attention for its potential application as a jet fuel. The high temperature and high light-tolerant photosynthetic cyanobacterium Synechococcus elongatus UTEX 2973 (hereafter Synechococcus 2973), whose doubling time is as short as 1.5 h, has great potential for synthesizing β-caryophyllene using sunlight and CO₂. In this study, a production of ~121.22 μg/L β-caryophyllene was achieved at 96 h via a combined strategy of pathway construction, key enzyme optimization and precursor supply enhancement. In addition, a final production of ~212.37 μg/L at 96 h was realized in a high-density cultivation. To our knowledge, this is the highest production reported for β-caryophyllene using cyanobacterial chassis and our study provide important basis for high-density fuel synthesis in cyanobacteria.


Subject(s)
Biofuels/microbiology , Carbon Dioxide/metabolism , Light , Photosynthesis , Synechococcus/radiation effects
16.
Article in Chinese | WPRIM | ID: wpr-878788

ABSTRACT

Evaporative light scattering detector(ELSD) and charged aerosol detector(CAD) methods were established in this study for the content determination of four kinds of sugars in Zhusheyong Yiqi Fumai(YQFM), and the factors affecting the accuracy of CAD methods were discussed. HPLC-ELSD chromatographic separation was performed on a Shodex Asahipak NH2 P-50 column with acetonitrile-water(75∶25)as the mobile phase, with a flow rate of 0.8 mL·min~(-1), drift tube temperature of 80 ℃. The analysis by HPLC-CAD was performed on the same column with acetonitrile-water as mobile phase for gradient elution, with a flow rate of 0.8 mL·min~(-1), a neb temperature of 45 ℃, and power function(PF) of 1.3. The samples of YQFM were detected by ELSD and CAD respectively. It was found that YQFM was composed of fructose, glucose, sucrose and maltose. The linear relationship of the two methods was good, and the recoveries, reproducibility and stability of these four kinds of sugars measured by the two methods satisfied the requirements of methodology. Both CAD and ELSD detectors were accurate and reliable in detecting saccharides components in YQFM. In addition, it was revealed in this study for the first time that the PF parameter of CAD had an important influence on the accuracy of sugar determination and acted as the key parameter of CAD method. It was also found that for CAD, a non-linear detector, there was no significant difference between the results of linear regression and logarithmic regression.


Subject(s)
Aerosols , Carbohydrates , Chromatography, High Pressure Liquid , Light , Reproducibility of Results , Scattering, Radiation , Sugars
17.
Article in Chinese | WPRIM | ID: wpr-826682

ABSTRACT

OBJECTIVE@#To explore the clinical therapeutic effect of light and heat of moxibustion for knee osteoarthritis (KOA).@*METHODS@#A total of 216 patients with KOA were randomized into a traditional moxibustion group (72 cases, 8 cases dropped off), a moxibustion light group (72 cases, 9 cases dropped off) and a moxibustion heat group (72 cases, 10 cases dropped off).The special light-heat separation moxibustion cup was applied, the patients in the traditional moxibustion group received the treatment of moxibustion, the patients in the moxibustion light group received the treatment of moxibustion light and the patients in the moxibustion heat group received the treatment of moxibustion heat. The acupoint selection of the three groups was Neixiyan (EX-LE 4), Dubi (ST 35) and Zusanli (ST 36), the treatment was given 20 min each time, 3 times a week, 4 weeks were required totally, and the follow-up surveys were made 4 and 8 weeks after treatment. The scores of Western Ontario and McMaster University osteoarthritis index (WOMAC) and visual analogue scale (VAS) were observed before treatment, after 2 and 4 weeks of treatment, 4 and 8 weeks after treatment. The therapeutic effects were evaluated according to the criterion of patient global assessment (PGA) after 4 weeks of treatment and 8 weeks after treatment.@*RESULTS@#Compared with before treatment, the pain scores, stiffness scores, physical function scores and total scores of WOMAC were reduced after 2, 4 weeks of treatment and 4 weeks after treatment in the three groups (<0.05). The pain scores, stiffness scores, physical function scores and total scores of WOMAC were reduced 8 weeks after treatment in the traditional moxibustion group and the moxibustion heat group (<0.05). The stiffness score, physical function score and total score of WOMAC were reduced 8 weeks after treatment in the moxibustion light group (<0.05). The pain score, physical function score and total score of WOMAC in the traditional moxibustion group after 4 weeks of treatment were lower than the moxibustion light group (<0.05). Compared with before treatment, the VAS scores were reduced after 2, 4 weeks of treatment and 4 , 8 weeks after treatment in the three groups (<0.05). The improvement rates in the traditional moxibustion group and the moxibustion heat group after 4 weeks of treatment and 8 weeks after treatment were superior to the moxibustion light group (<0.05).@*CONCLUSION@#The light and heat of moxibustion have therapeutic effect for KOA, and the therapeutic effect of moxibustion heat is superior to moxibustion light.


Subject(s)
Acupuncture Points , Hot Temperature , Humans , Light , Moxibustion , Osteoarthritis, Knee , Therapeutics , Treatment Outcome
18.
Article in Chinese | WPRIM | ID: wpr-828889

ABSTRACT

OBJECTIVE@#To develop a fast, sensitive and cost-effective method based on resonance light scattering (RLS) for characterization of protein solubility to facilitate detection of changes in solubility of mutant proteins.@*METHODS@#We examined the response curve of RLS intensities to the protein concentrations in synchronous scanning mode. The curve intersection points were searched to predict the maximal concentrations of the protein in dispersion state, which defined the solubility of the protein in this given state. Bovine serum albumin (BSA, 0-50 g/L) was used as the model to investigate the influences of pH values (6.5, 7.0, and 7.4) and salt concentrations (0.05, 0.10, 0.15, and 0.20 mol/L) on the determined solubility. The solubility of glutathione S-transferase isoenzymes alpha (GSTA, 0-27.0 g/L) and Mμ (GSTM, 0-20.0 g/L) were estimated for comparison. The RLS-based method was used to determine the solubility of uricase (MGU, 0-0.4 g/L) to provide assistance in improving the solubility of its mutants.@*RESULTS@#We identified two intersection points in the RLS response curves of the tested proteins, among which the lower one represented an approximation of the maximal concentration (or the solubility of the protein) in single molecular dispersion, and the higher one the saturated concentration of the protein in multiple molecular aggregation. In HEPES buffer, the two intersection points of BSA (isoelectric point 4.6) both increased with the increase of pH (6.5-7.4), and their values were ~1.2 g/L and ~33 g/L at pH 7.4, respectively; the latter concentration approached the solubility of commercial BSA in the same buffer at the same pH. The addition of NaCl reduced the values of the two intersection points, and increasing salt ion concentration decreased the values of the lower intersection points. Further characterizations of GSTA and GSTM showed that the low concentration intersection points of the two proteins were ~0.7 g/L and ~0.8 g/L, and their high concentration intersection points were ~10 g/L and ~11 g/L, respectively, both lower than those of BSA, indicating the feasibility of the direct characterization of protein solubility by RLS. The two concentration intersection points of MGU were 0.24 g/L and 0.30 g/L, respectively, and the low concentration intersection point of its selected mutant was increased by 2 times.@*CONCLUSIONS@#RLS allows direct characterization of the solubility of macromolecular proteins. This method, which is simple and sensitive and needs only a small amount of proteins, has a unique advantage for rapid comparison of solubility of low-abundance protein mutants.


Subject(s)
Hydrogen-Ion Concentration , Light , Scattering, Radiation , Solubility , Spectrum Analysis
19.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1703-1711, set.-out. 2019. tab, graf
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1038652

ABSTRACT

Este trabalho teve como objetivo avaliar o valor nutritivo e a força de cisalhamento da cultivar de Urochloa brizantha (syn Brachiaria brizantha) cv Xaraés submetida a três intensidades luminosas e quatro cortes. O experimento foi conduzido na FMVZ - Unesp de Botucatu, com delineamento experimental em blocos ao acaso, sendo os tratamentos: luminosidade natural, redução de 30% e 60% de luz, com quatro cortes e três repetições. As análises realizadas foram: composição bromatológica, digestibilidade e a força de cisalhamento. Não houve diferença na digestibilidade entre os tratamentos em nenhum dos cortes, mas a qualidade forrageira foi influenciada pelos níveis de intensidade de luz, tendo o tratamento com 60% de redução de luminosidade apresentado maiores concentrações de proteína bruta e cinzas, menores teores de fibra em detergente neutro, hemicelulose, celulose e força de cisalhamento. Em relação aos cortes estudados, o primeiro teve o menor intervalo de corte e produziu forragem com qualidade superior em comparação ao último, pois obteve menor teor de fibra em detergente ácido, lignina, hemicelulose, celulose e consequente menor força de cisalhamento. Portanto, a redução de 60% de luminosidade é benéfica à qualidade e à força de cisalhamento da cultivar Xaraés.(AU)


This study aimed to evaluate the nutritive value and shear strength of the Xaraés grass (Urochloa brizantha) under the three intensities of light and four cuts. The experiment was conducted at FMVZ - UNESP, Botucatu, with a randomized block design, with the following treatments: natural luminosity, 30% and 60% light reduction, with four cuts and three replications. The analyzes were bromatological composition, digestibility, and shearing strength. There was no difference in digestibility between the treatments in any of the cuts, forage quality was influenced by the light intensity levels, and the treatment with 60% of light reduction produced higher concentrations of crude protein and ash, lower levels of neutral detergent fiber, hemicellulose, cellulose and shear strength. According to the studied cuts, the first one had the lowest cut interval and produced superior forage compared with the last one, as it obtained lower fiber content in acid detergent, lignin, hemicellulose, cellulose and consequent lower shear force. Therefore, the reduction of 60% of luminosity is beneficial to the quality and shear force of the Xaraés palisade grass.(AU)


Subject(s)
Pasture/analysis , Pasture/methods , Food Analysis/methods , Poaceae/growth & development , Poaceae/physiology , Light
20.
Braz. j. biol ; 79(3): 404-409, July-Sept. 2019. tab
Article in English | LILACS | ID: biblio-1001466

ABSTRACT

Abstract Passion fruits species presents a larger economic importance for in natura consumption and industry. The main way to propagate these species is by seeds; however, the aril presence and environmental conditions may inhibit the seeds germination. In this sense, the objective of this study was to evaluate the effect of aril removal methods and light conditions on P. edulis var. flavicarpa seeds quality and germination. There were used five methods to remove the seeds aril: (1) friction on steel mesh sieve for 5 minutes; (2) friction with coarse sand on steel mesh sieve for 5 minutes; (3) immersion in lime solution at 10% (w/v), for 30 minutes; (4) fermentation in sugar solution at 10% (w/v), during 48 hours; and (5) natural pulp fermentation, during five days. The seeds were submitted to germination test at darkness and lightness, as well as, to length seedlings and emergence test. Regardless the aril removal method, the germination percentage was lower at lightness than darkness highlighting the natural pulp fermentation treatment, which presented 86% of seeds germinated. On the other hand, the aril removal methods did not affect the seedlings emergence, with emergence percentages ranged from 88 to 94%.


Resumo As espécies de maracujá apresentam grande importância econômica, tanto para o consumo in natura, quanto para a indústria. A principal maneira de propagar essas espécies é por sementes; contudo, a presença de arilo e condições ambientais pode inibir a germinação. Nesse sentido, objetivou-se estudar o efeito de métodos de remoção do arilo e luminosidade na qualidade e germinação das sementes de Passiflora edulis var. flavicarpa. Cinco métodos foram empregados para a remoção do arilo: (1) fricção em peneira de malha de aço por cinco minutos; (2) fricção com areia grossa em peneira de malha de aço por cinco minutos; (3) imersão em solução de cal a 10% (m/v), por 30 minutos; (4) fermentação da polpa em solução de açúcar a 10% (m/v), por 48 horas; e (5) fermentação natural da polpa, por cinco dias. As sementes foram submetidas ao teste de germinação no escuro e no claro, teste de comprimento de plântulas e teste de emergência. Independente do método de remoção do arilo, a porcentagem de germinação no claro apresentou-se menor em comparação ao escuro, com destaque para o tratamento de fermentação natural da polpa, o qual apresentou 86% de sementes germinadas. Por outro lado, os métodos de remoção do arilo não afetaram a emergência das plântulas, com porcentagem de emergência variando entre 88 a 94%.


Subject(s)
Seeds/physiology , Germination/physiology , Passiflora/physiology , Flowers/physiology , Seeds/growth & development , Seeds/radiation effects , Passiflora/growth & development , Passiflora/radiation effects , Seedlings/physiology , Light
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