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1.
Acta cir. bras ; 38: e386023, 2023. graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1527584

ABSTRACT

Purpose: After partial hepatectomy (PH), the remaining liver (RL) undergoes regenerative response proportional to the host. Limited literature exists on hepatic viability after tissue injury during hypothermic preservation. Spectroscopy measures cellular fluorescence and is explored for tissue characterization and parameter investigation. This study aimed to assess fluorescence analysis (spectroscopy) in evaluating liver viability and its relationship with hepatic tissue regeneration 24 hours after PH. Additionally, we analyzed liver regeneration in RL after 70% partial hepatectomy under hypothermic conditions with laser irradiation. Methods: Fifty-six Wistar rats were divided into four groups: total non-perfused liver (control), total perfused liver, partial hepatectomy "in situ", and partial hepatectomy "ex situ". Tissue analysis was performed at 0 and 24 hours using spectroscopy with laser devices emitting at 532 (green) and 405 nm (violet). Results: Spectroscopy identified tissue viability based on consistent results with Ki67 staining. The fluorescence spectra and Ki67 analysis displayed similar patterns, linking proliferative activity and absorption intensity. Conclusions: Fluorescence spectroscopy proves to be promising for real-time analysis of cellular activity and viability. Metabolic activity was observed in groups of live animals and hypothermically preserved samples, indicating cellular function even under blood deprivation and hypothermic conditions.


Subject(s)
Animals , Rats , Spectrometry, Fluorescence , Ischemia , Lasers , Liver/injuries
2.
Journal of Forensic Medicine ; (6): 40-44, 2023.
Article in English | WPRIM | ID: wpr-984178

ABSTRACT

OBJECTIVES@#To establish a rapid and nondestructive identification method for human body fluid stains and non-biological stains using three-dimensional fluorescence spectroscopy.@*METHODS@#The collected three-dimensional fluorescence spectrum data of human saliva, 3% blood, coffee and Fanta® stains were processed with dimensionality reduction. After wavelet transform, spectral denoising and feature extraction, the classification formula was established. The Fisher discriminant was used for spectrum matching and recognition to establish the analysis method to distinguish stain types.@*RESULTS@#According to the results of data training and comparison, all the recognition accuracies of Fanta®, coffee, saliva and blood were more than 91.39%. Among them, saliva reached 100% recognition accuracy.@*CONCLUSIONS@#Three-dimensional fluorescence spectroscopy is a potential method for rapid and nondestructive identification of biological and non-biological stains.


Subject(s)
Humans , Forensic Medicine/methods , Coloring Agents/analysis , Coffee , Spectrometry, Fluorescence , Body Fluids/chemistry
3.
Biol. Res ; 55: 34-34, 2022. ilus, tab, graf
Article in English | LILACS | ID: biblio-1403572

ABSTRACT

BACKGROUND: The assessment of oocyte quality is, nowadays, a major challenge in aquaculture, oocyte cryopreservation, and environmental science. Oocyte quality is a determining factor in fertilization and embryo development; however, there is still a lack of rapid and sensitive cellular markers for its assessment. Currently, its estimation is pre-dominantly based on morphological analysis, which is subjective and does not consistently reflect the developmental competence of the oocytes. Despite several recent studies investigating molecular markers related to oocyte quality, methods currently available for their determination pose various technical challenges and limitations. In this study, we developed a novel approach based on fluorescence spectroscopy to assess different intrinsic physiological parameters that can be employed to evaluate egg quality in marine invertebrates that are widely used as animal models such as sea urchins and mussels. RESULTS: Different physiological parameters, such as viability, mitochondrial activity, intracellular ROS levels, plasma membrane lipid peroxidation, and intracellular pH, for egg quality evaluation have been successfully assessed in sea urchins and mussels by using specific fluorescent dyes and detecting the fluorescent signals in eggs through fluorescence spectroscopy. CONCLUSIONS: Based on our findings, we propose these physiological markers as useful predictors of egg quality in marine invertebrates; they can be estimated rapidly, selectively, and sensitively by employing this novel approach, which, due to the speed of analysis, the low cost, and easy use can be considered a powerful analytical tool for the egg quality assessment.


Subject(s)
Animals , Oocytes/metabolism , Embryonic Development , Sea Urchins , Spectrometry, Fluorescence , Cryopreservation/methods
4.
Acta cir. bras ; 37(9): e370905, 2022. graf
Article in English | LILACS, VETINDEX | ID: biblio-1413625

ABSTRACT

Purpose: Fluorescence spectroscopy techniques have been investigated aiming to reduce the invasiveness of methods for investigation of tissue. In transplantation procedures, it may offer the possibility of a complementary technique for the monitoring of liver grafts' conditions prior to and during the transplantation procedure stages involving cold perfusion. The objective of this study was to evaluate fluorescence spectroscopy under violet light excitation (408 nm) for the monitoring of clinical hypothermic liver transplantation procedures. Methods: Organ grafts were monitored from before the removal of the donor's body to 1 h after the implant into the receptor's body. Fluorescence spectroscopy was assessed over five stages within these transplant stages. Results: The study provided evidence of a correlation between fluorescence information collected during liver grafts transplantation and the survival of patients. Conclusions: Fluorescence spectroscopy can become a tool to monitor transplantation grafts, providing objective information for the final decision of surgeons to use organs.


Subject(s)
Humans , Spectrometry, Fluorescence/methods , Ultraviolet Rays , Liver Transplantation/rehabilitation
5.
Braz. dent. sci ; 23(2): 1-8, 2020. ilus
Article in English | LILACS, BBO | ID: biblio-1095886

ABSTRACT

Objective: This work aims to use new spectroscopic and radiographic methods to study the dental hard tissue erosion and abfraction, as these lesions are actually quite difficult to be diagnosed in clinical practice. Material and Methods: This in vivo study was conducted on 60 patients with early erosion and 60 patients with abfraction at the cervical area by means of laser-induced fluorescence (LIF) and multilayer spiral computed tomography (MSCT). Results: In comparative dental hard tissues studies LIF spectra from intact and affected areas, it was noted multidirectional fluorescence intensity dependence between areas affected by abfraction and intact areas. MSCT technique allowed assessing the degree of damaged areas, especially at deeper stages. Conclusion: Although LIF and MSCT methods presented limitations, it was shown their effectiveness in the diagnosis of abfraction and erosion by detecting changes in the morphological structure as well as in the chemical and mineral composition of affected dental hard tissues. So LIF and MSCT methods can be successfully used in order to develop new medical devices which will provide most accurate clinical diagnose of different stages of dental erosion and abfraction.(AU)


Objetivo: Este trabalho tem como objetivo utilizar novos métodos espectroscópicos e radiográficos para estudar a erosão e a abração do tecido duro dentário, pois essas lesões são realmente bastante difíceis de serem diagnosticadas na prática clínica. Material e Métodos: Este estudo in vivo foi realizado em 120 pacientes com erosão e abração precoces na área cervical por meio de fluorescência induzida por laser (LIF) e tomografia computadorizada em espiral multicamada (MSCT). Resultados: Em estudos comparativos espectros de LIF, de tecidos duros dentais intactos e afetados, observouse dependência da intensidade da fluorescência multidirecional entre as áreas afetadas pela abração e as áreas intactas. A técnica MSCT permitiu avaliar o grau de áreas danificadas, principalmente em estágios mais profundos. Conclusão: Embora os métodos LIF e MSCT tenham apresentado limitações, foi demonstrada sua eficácia no diagnóstico de abração e erosão, detectando alterações na estrutura morfológica e na composição química e mineral dos tecidos duros afetados. Portanto, os métodos LIF e MSCT podem ser utilizados com sucesso, a fim de desenvolver novos dispositivos médicos que fornecerão um diagnóstico clínico mais preciso de diferentes estágios de erosão e abração dentária.(AU)


Subject(s)
Humans , Spectrometry, Fluorescence , Tooth Erosion , Tooth Demineralization , Tomography, Spiral Computed
6.
Braz. J. Pharm. Sci. (Online) ; 56: e18544, 2020. graf
Article in English | LILACS | ID: biblio-1132048

ABSTRACT

The purpose of the study was to evaluate the antibacterial effect of protoporphyrin IX (PpIX) generated by the exogenous administration of 5-aminolevulinic acid or δ-ALA and activated with an argon laser over a planktonic and biofilm of Enterococcus faecalis (E. faecalis) as a pharmacological therapy alternative. A planktonic strain of E. faecalis was cultured with a solution of ∂-ALA (40 µg/mL)-thioglycolate solution for 13 min, and a biofilm of E. faecalis was cultured in a δ-ALA (80 µg/mL)-thioglycolate solution for 13 min. Then, both were irradiated with an argon laser. Finally, the antibacterial effect was evaluated by counting the CFU in planktonic form, and a LIVE/DEAD viability cell test. The production and accumulation of PpIX from exogenously administered δ-ALA on E. faecalis in planktonic and biofilm forms was confirmed by spectrofluorometry. The irradiation of PpIX with an argon laser produced an antibacterial effect on E. faecalis in planktonic and biofilm form, even without biofilm disruption, at a concentration of 40 µg/mL and 80 µg/mL of δ-ALA, respectively. The exogenous administration of δ-ALA in combination with laser irradiation on planktonic and biofilm forms of E. faecalis produces an effective antibacterial effect as complement or alternative to pharmacological therapies


Subject(s)
Protoporphyrins/adverse effects , Enterococcus faecalis/classification , Photochemotherapy/methods , Spectrometry, Fluorescence/methods , Cells , Biofilms , Drug Therapy , Aminolevulinic Acid/administration & dosage
7.
Chinese Journal of Biotechnology ; (12): 2877-2891, 2020.
Article in Chinese | WPRIM | ID: wpr-878537

ABSTRACT

Studies on the interaction between small organic molecules and DNA are important means to explore drug mechanism and new drugs. Quercetin is a polyhydroxy flavone compound with activities such as anti-cancer, anti-inflammatory, antibacterial, antiviral, hypoglycemic and anti-hypertensive, immunomodulation and cardiovascular protection. Experimental studies aim at confirming if an interaction exists between quercetin and DNA, and determining the type of interaction. The interaction between quercetin and herring DNA can be detected by fluorescence spectrometry and resonance scattering fluorescence spectrometry analysis. The mode of the interaction between quercetin and herring DNA can be detected by UV-Vis spectrophotometry and fluorescence polarization analysis. This review helps understand the in vitro interaction between quercetin and DNA, and assist the development of drugs for corresponding diseases.


Subject(s)
DNA/genetics , Quercetin , Spectrometry, Fluorescence
8.
China Journal of Chinese Materia Medica ; (24): 2559-2565, 2019.
Article in Chinese | WPRIM | ID: wpr-773226

ABSTRACT

Small molecules with physiological or pharmacological activities need to interact with biological macromolecules in order to function in the body. As the protein with the highest proportion of plasma protein,serum albumin is the main protein binding to various endogenous or exogenous small molecules. Serum albumin interacts with small molecules in a reversible non-covalent manner and transports small molecules to target sites. Bovine serum albumin( BSA) is an ideal target protein for drug research because of its low cost and high homology with human serum albumin. The research on the interaction between drugs and BSA has become a hotspot in the fields of pharmacy,medicine,biology and chemistry. In this research,molecular docking method was used to study the interaction between three small ginsenosides with high pharmacological value( Rg_1,Rb_1,Ro) and bovine serum albumin( BSA),and the binding mode information of three ginsenosides interacting with BSA was obtained. The results of molecular docking showed that ginsenosides and amino acid residues in the active pocket of proteins could be combined by hydrophobic action,hydrogen bonding and electrostatic action. The interaction between small ginsenosides and bovine serum albumin is not the only form,and their interaction has many forms of force. The interaction between these molecules and various weak forces is the key factor for the stability of the complex. The results of this study can provide the structural information of computer simulation for the determination of the interaction patterns between active components and proteins of ginseng.


Subject(s)
Animals , Cattle , Binding Sites , Computer Simulation , Ginsenosides , Chemistry , Molecular Docking Simulation , Protein Binding , Serum Albumin, Bovine , Chemistry , Spectrometry, Fluorescence , Thermodynamics
9.
Int. j. morphol ; 36(2): 435-440, jun. 2018. graf
Article in English | LILACS | ID: biblio-954133

ABSTRACT

Parkinson's disease (PD) is described as a neurological condition, resulting from continuous degeneration of dopaminergic neurons. Currently, most treatments for neurodegenerative diseases are palliative. In traditional Iranian medicine, Citrus aurantium flower extract is used to treat some neural diseases, such as sleep disorders and anxiety. The tendency towards the use of medicinal herbs for the treatment of diseases (eg, seizure) is growing. Accordingly, we evaluated the antioxidant effects of C. aurantium flowers and analyzed their protective effects against 6-hydroxydopamine (6-OHDA)-mediated oxidative stress. In this study, 150 mM of 6-OHDA was used to induce cellular damage. Also, MTT assay was performed to analyze cellular viability. Fluorescence spectrophotometry was performed to measure the intracellular reactive oxygen species (ROS) and calcium levels. Based on the findings, 6-OHDA could reduce cell viability. We also analyzed the effects of C. aurantium against neurotoxicity. The intracellular levels of ROS and calcium greatly improved in cells exposed to 6-OHDA. SH-SY5Y cell incubation with C. aurantium (400 and 600 mg/mL) induced protective effects and decreased the biochemical markers of cell apoptosis. According to the findings, C. aurantium showed protective effects against neurotoxicity, caused by 6-OHDA; these protective properties were accompanied by antiapoptotic features. According to the findings, it seems that hydromethanolic C. aurantium extract can be used to prevent seizures.


La enfermedad de Parkinson (EP) se describe como una afección neurológica que resulta de la degeneración continua de las neuronas dopaminérgicas. Actualmente, la mayoría de los tratamientos para las enfermedades neurodegenerativas son paliativos. En la medicina tradicional iraní, el extracto de flor de Citrus aurantium se usa para tratar algunas enfermedades neurológicas, como los trastornos del sueño y la ansiedad. La tendencia hacia el uso de las medicinas para el tratamiento de enfermedades (por ejemplo, convulsiones) está creciendo. Por consiguiente, el objetivo de este trabajo consistió en evaluar los efectos antioxidantes de las flores de C. aurantium y analizar sus efectos protectores contra el estrés oxidativo mediado por la 6- hidroxidopamina (6-OHDA). En este estudio, se usó 150 mM de 6-OHDA para inducir daño celular. Además, se realizó un ensayo de MTT para analizar la viabilidad celular. La espectrofotometría de fluorescencia se realizó para medir las especies reactivas de oxígeno (ROS) intracelulares y los niveles de calcio. En base a los hallazgos, 6-OHDA podría reducir la viabilidad celular. También analizamos los efectos de C. aurantium contra la neurotoxicidad. Los niveles intracelulares de ROS y calcio se expandieron a las células expuestas a 6-OHDA. La incubación de células SH-SY5Y con C. aurantium (400 y 600 mg / ml) indujo efectos protectores y disminuyó los marcadores bioquímicos de la apoptosis celular. De acuerdo con los hallazgos, C. aurantium mostró efectos protectores contra la neurotoxicidad, causada por 6-OHDA; estas propiedades protectoras fueron acompañadas por características antiapoptóticas. Según los hallazgos, parece que el extracto hidrometanólico de C. aurantium se puede usar para prevenir las convulsiones.


Subject(s)
Humans , Parkinson Disease , Plant Extracts/pharmacology , Citrus/chemistry , Antioxidants/pharmacology , Spectrometry, Fluorescence , Cell Survival/drug effects , Blotting, Western , Reactive Oxygen Species , Apoptosis/drug effects , Oxidative Stress/drug effects , Neuroprotective Agents , Cell Culture Techniques , Cell Line, Tumor , Hydroxydopamines/toxicity , Neuroblastoma
10.
Pesqui. bras. odontopediatria clín. integr ; 17(1): e3389, 13/01/2017. tab, ilus, graf
Article in English | LILACS, BBO | ID: biblio-914260

ABSTRACT

Objective: To investigate the antifungal potential of A. colubrina, and its phytochemical characteristics, thermal profile and toxicity. Material and Methods: To assess potential antifungal activity, the technique of microdilution was used with the determination of the Minimum Inhibitory Concentration and Minimum Fungicidal Concentration, using standard species of Candida and recent clinical isolates of Candida albicans. Analyses of action of the extract were performed on the wall and cell morphology of C. albicans, of the interactive effect between the plant extract and nystatin on C. albicans through the checkerboard method, and of growth kinetics. The phytochemical screening was determined by spectrophotometry. The thermal profile was traced with the determination of thermogravimetric curves (TG) and differential scanning calorimetry (DSC). The toxicity was evaluated by the method of hemolysis. Results: The extract of A. colubrina showed a fungistatic potential against all bacteria tested and it acted by modifying the cellular morphology of C. albicans. There was a synergism between nystatin and the plant extract (FIC=0.375), and 53.18% of total polyphenols were determined. The TG curve showed the occurrence of three steps of thermal decomposition. None of the tested concentrations became the effective cytotoxic concentration. Conclusion: Further studies should be conducted to understand the efficacy and the mechanisms of action involved in the antifungal activity of the plant extract of A. colubrina in order to produce a new drug for the treatment of oral candidiasis.


Subject(s)
Antifungal Agents , Candida albicans/immunology , Plant Extracts , Plants, Medicinal , Anti-Infective Agents , Brazil , Spectrometry, Fluorescence/methods
11.
Vitae (Medellín) ; 24(2): 113-123, 2017. Ilustraciones
Article in English | LILACS, COLNAL | ID: biblio-994663

ABSTRACT

Background: Several investigations report to rosemary as a plant rich in bioactive components with antioxidant potential, in this work, a rosemary extract was obtained that combined with ascorbyl palmitate provides a synergistic protection to a high fat diet (palm olein). Objectives: The objective of this study was to evaluate the effect of the addition of two extracts of rosemary (Rosmarinus officinalis): AP10R and AP30R at three concentrations of 1000, 1500 and 2000 ppm, on the oxidative stability of palm oil subjected to accelerated oxidation conditions and in a frying process. Methods: Lipid peroxidation of palm olein with and without antioxidants was monitored by measuring the concentration of hydroperoxides and total polar compounds; the thermal stability of the phenolic compounds in the oil was evaluated by fluorescence spectroscopy. Results: The AP10R extract at 2000 ppm inhibited olein oxidation by 30% and 60% in terms of total hydroperoxide and polar concentrations, respectively. The AP30 extract at 2000 ppm had similar inhibition behaviors with values of 27% of total hydroperoxides and 54% by total polar compounds in a time from 20 to 25 h. Conclusions: The results indicated that heating reduces the concentration of polyphenols; this decrease was more evident in olein without antioxidants, reflecting the effect of the polyphenols of rosemary extract on the thermal stability of palm olein.


Antecedentes: Diversas investigaciones reportan al romero como una planta rica en componentes bioactivos con potencial antioxidante, en este trabajo, se obtuvo un extracto de romero que combinado con ascorbil palmitato brinda una protección sinérgica a un sistema alimenticio con alto contenido graso (oleína de palma). Objetivos: El objetivo de este estudio fue evaluar el efecto de la adición de dos extractos de romero (Rosmarinus officinalis): AP10R y AP30R a tres concentraciones de 1000, 1500 y 2000 ppm, sobre la estabilidad oxidativa del aceite de palma sometido a condiciones de oxidación acelerada y en un proceso de fritura. Métodos: La peroxidación lipídica de la oleína de palma con y sin antioxidantes fue monitoreada midiendo la concentración de hidroperóxidos y los compuestos polares totales; la estabilidad térmica de los compuestos fenólicos en el aceite se evaluó por espectroscopia de fluorescencia. Resultados: El extracto AP10R a 2000 ppm inhibió la oxidación de oleína en 30% y 60% en términos de la concentración de hidroperóxidos y polares totales, respectivamente. El extracto AP30 a 2000 ppm tuvo comportamientos similares de inhibición con valores de 27% para hidroperóxidos y 54% para el contenido de fenoles totales en un tiempo de 20 a 25 h. Conclusiones: Los resultados indicaron que el calentamiento disminuye la concentración de polifenoles; esta disminución fue más evidente en la oleína sin antioxidantes, reflejando el efecto de los polifenoles del extracto de romero sobre la estabilidad térmica de la oleína de palma.


Subject(s)
Humans , Palmitates , Spectrometry, Fluorescence , Palm Oil , Antioxidants
12.
Journal of Zhejiang University. Medical sciences ; (6): 1-6, 2017.
Article in Chinese | WPRIM | ID: wpr-300831

ABSTRACT

To investigate the effects of neuronal histamine on spatial memory acquisition impairment in rats with pentylenetetrazole-kindling epilepsy, and to explore its mechanisms.A subconvulsive dose of pentylenetetrazole (35 mg/kg) was intraperitoneally injected in rats every 48 h to induce chemical kindling until fully kindled. Morris water maze was used to measure the spatial memory acquisition of the rats one week after fully pentylenetetrazole-kindled, and the histamine contents in different brain areas were measured spectrofluorometrically. Different dosages of hitidine (the precursor of histamine), pyrilamine (H1 receptor antagonist), and zolantidine (H2 receptor antagonist) were intraperitoneally injected, and their effects on spatial memory acquisition of the rats were observed.Compared with control group, escape latencies were significantly prolonged on Morris water maze training day 2 and day 3 in pentylenetetrazole-kindling epilepsy rats (all<0.05); and the histamine contents in hippocampus, thalamus and hypothalamus were decreased significantly (all<0.05). Escape latencies were markedly shortened on day 3 by intraperitoneally injected with histidine 500 mg/kg, and on day 2 and day 3 by intraperitoneally injected with histidine 1000 mg/kg in pentylenetetrazole-kindling epilepsy rats (all<0.05). The protection of histidine was reversed by zolantidine (10 and 20 mg/kg), but not by pyrilamine.Neuronal histamine can improve the spatial memory acquisition impairment in rats with pentylenetetrazole-kindling epilepsy, and the activation of H2 receptors is possibly involved in the protective effects of histamine.


Subject(s)
Animals , Rats , Benzothiazoles , Pharmacology , Brain Chemistry , Epilepsy , Hippocampus , Chemistry , Histamine H1 Antagonists , Pharmacology , Histamine H2 Antagonists , Pharmacology , Histidine , Pharmacology , Hypothalamus , Chemistry , Kindling, Neurologic , Physiology , Memory Disorders , Drug Therapy , Pentylenetetrazole , Phenoxypropanolamines , Pharmacology , Piperidines , Pharmacology , Pyrilamine , Pharmacology , Rats, Sprague-Dawley , Receptors, Histamine H2 , Physiology , Spatial Memory , Spectrometry, Fluorescence , Thalamus , Chemistry
13.
Bauru; s.n; 2017. 143 p. tab, ilus, graf.
Thesis in Portuguese | LILACS, BBO | ID: biblio-880165

ABSTRACT

A adição de corantes fluorescentes a adesivos odontológicos possibilita a investigação da distribuição espacial desses materiais na interface dente-restauração, utilizando-se a microscopia confocal de varredura a laser (MCVL). A literatura indica falta de padronização na aplicação de agentes fluorescentes com tal finalidade. Esse estudo sistematizou estratégias para a adição de rodamina B (RB) e fluoresceína sódica (FS) a um sistema adesivo convencional de três passos, Adper Scotchbond Multi-Purpose (MP), e um autocondicionante de dois passos, Clearfil SE Bond (SE), considerados "padrão-ouro" na Odontologia. Os objetivos principais foram (a) determinar a menor faixa de concentrações de RB e FS necessária para produzir imagens satisfatórias da interface dentina-adesivo e (b) avaliar o efeito da adição desses corantes sobre algumas propriedades das resinas. Os adesivos foram marcados com RB ou FS em concentrações decrescentes (0,5, 0,1, 0,02 e 0,004 mg/mL) por meio de um método de dispersão semidireto. O comportamento fotofísico/ fluorescente dos adesivos marcados foi investigado por espectroscopia de fotoluminescência e MCVL. Paralelamente, avaliaram-se os adesivos quanto ao grau de conversão (GC) e ao ângulo de contato (AC). Tanto os resultados de GC como os de AC foram submetidos à análise de variância com dois fatores (adesivo e tratamento) com α = 0,05, seguida de teste post-hoc de Tukey. Os máximos comprimentos de onda de emissão e de excitação da RB e da FS foram influenciados pelo meio polimérico e pela concentração de corante de modo geral. A MCVL preliminar de amostras de adesivo polimerizado, realizada sob condições experimentais padronizadas, mostrou que o comportamento fluorescente da RB em MP e SE foi muito semelhante na mesma concentração de corante, mas o mesmo não pôde ser dito do comportamento da FS, que foi notavelmente inferior no adesivo autocondicionante, SE, na concentração mais alta. Em dentina, os adesivos preparados com RB nas concentrações-alvo de 0,1 e 0,02 mg/mL apresentaram fluorescência ótima; já aqueles preparados com 0,004 mg/mL produziram fraco sinal. Adesivos preparados com FS a 0,5 mg/mL apresentaram ótima fluorescência na interface de adesão, enquanto que concentração menor desse corante não produziu sinal suficiente. Padrões morfológicos aparentemente atípicos foram observados na interface de adesão, quando da associação do adesivo SE com o corante FS. A adição de RB e FS nas quatro concentrações indicadas aos adesivos MP e SE não afetou o GC nem o AC em comparação com os grupos de controle correspondentes. Em suma, a RB mostra-se um corante mais versátil que a FS na avaliação morfológica das interfaces dentina-MP e dentina-SE via MCVL. A menor faixa de concentrações de RB nos adesivos MP e SE, na qual é possível produzir imagens satisfatórias das interfaces, situa-se entre 0,1­0,02 mg/mL. Já o corante FS deve ser adicionado a esses adesivos a pelo menos 0,5 mg/mL para produzir níveis de fluorescência satisfatórios na interface de adesão. A não ocorrência de efeitos deletérios sobre a polimerização e a molhabilidade das resinas estabelece uma margem de segurança para a incorporação desses agentes fluorescentes (em concentração ≤ 0,5 mg/mL) nesses sistemas monoméricos.(AU)


The addition of fluorescent dyes to dental adhesives makes it possible to investigate the spatial distribution of such resin-based materials in the tooth-restoration interface, using confocal laser scanning microscopy (CLSM). Literature indicates a lack of standardization on the application of fluorescent agents for this purpose. This work presents strategies for adding rhodamine B (RB) and fluorescein sodium salt (FS) to a three-step etch-and-rinse adhesive system, Adper Scotchbond Multi-Purpose (MP), and a two-step self-etching one, Clearfil SE Bond (SE), both regarded as "gold standard" in restorative dentistry. The main objectives were (a) to determine the lowest range of RB and FS concentrations required to produce suitable images of the dentin-adhesive interface via CLSM and (b) to investigate potential effects of addition of these dyes on some resin properties. The adhesives were labeled with RB or FS at decreasing concentrations (0.5, 0.1, 0.02 and 0.004 mg/mL) by means of a semi-direct dispersion method. The photophysical/fluorescent behavior of the labeled resins was investigated by photoluminescence spectroscopy and by CLSM. The adhesives were also investigated with regards to the degree of conversion (DC) and contact angle (CA). A two-way ANOVA of "adhesive" and "treatment" was conducted on DC and CA separately, followed by Tukey's test. The maximum emission and excitation wavelengths of RB and FS were influenced by the host polymer and the dye concentration in general. The preliminary CLSM of cured adhesive samples, performed with standardized settings, showed that the fluorescent behavior of RB in MP and SE was very similar in the same dye concentration, unlike the behavior of FS, which was lower in the self-etching adhesive for the highest dye concentration. In dentin, the adhesives prepared with RB at the target concentrations of 0.1 and 0.02 mg/mL presented optimal fluorescence; those with 0.004 mg/mL produced poor signal. Adhesives prepared with FS at 0.5 mg/mL presented optimal fluorescence at the bonding interface, whereas lower concentrations of FS did not produce sufficient signal. Atypical morphological features were observed at the bonding interface, when adhesive SE was used with FS. The addition of RB and FS at the four decreasing concentrations to adhesives MP and SE did not affect DC or CA compared to the corresponding controls. In short, RB is more versatile than FS for the morphological characterization of dentin-MP and dentin-SE interfaces via MCVL. The lowest range of RB concentrations in adhesives MP and SE that can produce suitable images of the bonding interface lies between 0.1­0.02 mg/mL. The dye FS should be added to these adhesives at 0.5 mg/mL at least to produce satisfactory fluorescence levels at the bonding interface. Since negative effects on polymerization and wettability of the resins were not observed, the use of RB and FS (in concentration ≤ 0.5 mg/mL) together with MP and SE should be reliable in terms of resin properties.(AU)


Subject(s)
Fluorescein/chemistry , Fluorescent Dyes/chemistry , Resin Cements/chemistry , Rhodamines/chemistry , Analysis of Variance , Ethanol/chemistry , Microscopy, Confocal , Reference Values , Reproducibility of Results , Self-Curing of Dental Resins/methods , Spectrometry, Fluorescence , Spectrophotometry, Infrared
14.
Bauru; s.n; 2017. 97 p. ilus, tab.
Thesis in Portuguese | LILACS, BBO | ID: biblio-880296

ABSTRACT

A obesidade e a síndrome metabólica têm aumentado em proporções preocupantes em nível mundial. Além das consequências sistêmicas, a obesidade e suas comorbidades também têm sido relacionadas com a condição bucal. O objetivo deste estudo foi identificar a progressão de lesões cariosas, presença de biofilme dentário, fluxo salivar e presença de saburra lingual em indivíduos eutróficos, sendo avaliados em dois momentos e portadores de síndrome metabólica antes e após a cirurgia bariátrica. A amostra foi constituída por 150 indivíduos, divididos em dois grupos: grupo controle (GC: 75) e grupo obeso (GO: 75), ambos avaliados em T0 e T1, sendo GC 6 meses após a primeira avaliação e GO 6 meses após a cirurgia bariátrica. A avaliação antropométrica dos indivíduos foi realizada por meio do IMC e circunferência da cintura. Os índices ICDAS II e CPOD foram utilizados para avaliar a progressão da cárie dentária. O método de fluorescência verde (QLF- Quantitative Light-induced Fluorescence) avaliou a perda mineral nas superfícies lisas dos dentes e presença de biofilme dentário. O fluxo salivar estimulado foi avaliado em mL/min. O Índice de Saburra Lingual foi utilizado para a avaliação da presença de saburra na língua. Para análise estatística, utilizou-se os testes Qui Quadrado, Exato de Fisher, Mann-Whitney, Kruskal-Wallis e Regressão Logística Múltipla, adotando nível de significância de 5%. Os resultados mostraram que houve diferença significativas entre os grupos, GC apresentou maior número de dentes hígidos (p=0,038) e dentes sem alteração no esmalte (p=0,005) quando comparado ao GO. Ao comparar GC e GO no T1, verificou-se que houve diferença significativa em relação ao CPOD (p<0,0001), dentes restaurados (p<0,0001) e área da lesão (Ws) (p=0,045), sendo as piores condições encontradas encontradas em GO. Observou-se que houve diferença significativa entre a perda mineral e quantidade de biofilme dentário por fluorescência entre os grupos, mas não entre T0 e T1. Diante dos resultados, podese concluir que indivíduos portadores de síndrome metabólica, comparado com os eutróficos, apresentam maior número de lesões cariosas antes e após a cirurgia bariátrica. No presente estudo a cirurgia bariátrica não interferiu na progressão das lesões cariosas, todavia, destaca-se a necessidade de abordagem multiprofissional e contínua, atuando na prevenção de doenças e atenção odontológica.(AU)


Obesity and the metabolic syndrome have increased in alarming proportions at world level. Apart from systemic consequences, obesity and its comorbidities have also been related to the oral condition. The aim of this study was to identify the caries lesion progression, presence of dental biofilm, the salivary flow and tongue coating in eutrophic individuals, being evaluated in two moments and individuals with metabolic syndrome before and after undergoing bariatric surgery. The sample consisted of 150 individuals divided into two groups: Control Group (CG: 75) and Obese Group (OG): 75, both evaluated in T0 and T1; CG being evaluated six months after T0, and EG, 6 months after bariatric surgery. Anthropometric assessment of individuals was made by means of BMI and waist circumference measurement. The ICDAS II and DMFT indices were used for evaluating the progression of dental caries. The Quantitative Light-induced Fluorescence (QLF) method, for evaluating mineral loss on the smooth tooth surfaces and the presence for dental biofilm. The stimulated salivary flow was evaluated in mL/min. The Winkel tongue coating index (WTCI) was used to evaluate the presence of tongue coating. For statistical analysis, the Chi- Square, Fishers Exact, Kruskal-Wallis and Multiple Logistic Regression tests were used, adopting a significance level of 5%. The results showed statistical difference between the groups: CG presented a higher; number of healthy teeth (p=0.038) and teeth without changes in enamel (p=0.005) when compared to OG. When comparing CG and EG after the second evaluation (T1), statistically significant difference was verified in relation to DMFT (p<0.0001), restored teeth (p<0.0001) and lesion area (Ws) (p=0.045), being the worst conditions found in OG. It was observed that there was a significant difference between mineral loss and the quantity dental biofilm by fluorescence between groups, but not between T0 and T1. In view of the results, the authors concluded that patients with metabolic syndrome, compared to eutrophic, have a higher number of caries lesions before and after bariatric surgery. In the present study, bariatric surgery did not influence in caries lesion progression, however, highlights the necessity to a continuous multi professional approach to acting in the prevention of diseases and dental care.(AU)


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Bariatric Surgery , Dental Caries/etiology , Dental Plaque/etiology , Metabolic Syndrome/complications , Obesity/complications , Obesity/surgery , Anthropometry , Biofilms , Case-Control Studies , Dental Caries/physiopathology , Dental Plaque/physiopathology , Metabolic Syndrome/physiopathology , Obesity/physiopathology , Prospective Studies , Spectrometry, Fluorescence/methods , Treatment Outcome
15.
Full dent. sci ; 7(26): 92-98, abr. 2016. ilus, tab
Article in Portuguese | LILACS, BBO | ID: lil-786852

ABSTRACT

A escala 3D-Master foi desenvolvida com a finalidade de satisfazer as maiores exigências estéticas dos pacientes, por possuir uma maior quantidade de tonalidades em relação às demais escalas. Contudo, possui uma técnica específica para a sua correta utilização, desconhecida por grande parte dos profissionais. O objetivo desse trabalho foi avaliar se, após o aprendizado da técnica correta de utilização da escala de cor VITA 3D-Master, recomendada pelo fabricante (VITA® Zahnfabrik, Alemanha), os profissionais da área de odontologia conseguem utilizá-la de forma adequada, atingindo o objetivo desejado que é a correta seleção de cor dos dentes. Para isso, foram utilizados seis elementos dentários de face vestibular hígida extraídos e doados pelos pacientes ao banco de dentes da faculdade. O terço médio da face vestibular de cada dente foi escolhido para a seleção de cor feita pelo espectrofotômetro digital VITA EasyShade programado para a escala VITA 3D-Master. Trinta e sete acadêmicos do último ano do curso de odontologia fizeram a seleção pelo método visual dos mesmos elementos dentários. Após a primeira seleção, uma palestra de 3 horas de duração foi ministrada por um técnico de prótese dental, ceramista e consultor da VITA®. Após essas orientações, os mesmos acadêmicos realizaram uma segunda seleção de cor com os mesmos elementos dentários, utilizando a técnica de seleção de cor da escala VITA 3D-Master. A técnica preconizada pela VITA® para a correta utilização da escala VITA 3D-Master impactou positivamente no resultado da segunda fase da pesquisa para a seleção de cor.


The 3D-Master shade guide was developed in order to meet higher patientsÆ aesthetic requirements as it has a greater number of shades when compared to other shade guides. However, a specific technique is needed for its correct use, which is unknown by most of professionals. The aim of this study was to evaluate if after learning the VITA 3D-Master shade guide correct technique use, recommended by the manufacturer (VITA® Zahnfabrik, Germany), dentistry professionals can use it properly, reaching the desired goal that is the correct selection of tooth color. For this, we used six extracted teeth of higid vestibular surface donated by patients to the university teeth bank. The middle third of the vestibular surface of each tooth was chosen for the color selection made by the digital spectrophotometer VITA Easyshade programmed for VITA 3D-Master shade guide. Thirty-seven students from the last year of the odontology course made the selection through the visual method in the same teeth. After the first selection, a 3 hours lecture was held by a qualified dental prosthetist, ceramist and VITA® consultant. After these guidelines, the same students performed a second color selection with the same teeth, using the VITA 3D-Master shade guide color selection technique. The technique recommended by VITA® for the correct use of VITA 3D-Master shade guide positively affected the outcome of the second phase of the research for color selection.


Subject(s)
Color Perception , Esthetics, Dental , Students, Dental , Brazil , Spectrometry, Fluorescence/methods , Cross-Sectional Studies/methods
16.
Braz. dent. sci ; 19(3): 53-58, 2016. ilus, tab
Article in English | LILACS, BBO | ID: biblio-830987

ABSTRACT

Objective: This study evaluated the effect of thickness on fluorescence of resin composites and tooth substrates (enamel and dentin). Material and methods: Ninety bovine incisors were used, resulting in 45 dentin and 45 enamel disks (6 mm diameter and 0.5, 1, or 1.5 mm in thickness). Ninety discs of Charisma, Filtek Z350 and IPS Empress Direct (for enamel and dentin) resins at same dimensions were built. Fluorescence measurements were performed using a fluorescence spectrophotometer (RF-5301PC, Shimadzu Corp) with excitation at 365 nm. Data were submitted to 2-way ANOVA and Tukey’s post hoc tests (α = 0.05). Results: The 2-way ANOVA revealed statistically significant differences for all factors, as well as the interaction between them (p <0.05). Dentin specimens (1.5 mm) showed highest fluorescence (128.33 A.U.), while Filtek Z350 (dentin - 1.0 mm) showed the lowest fluorescence (29.84 A.U.). Thickness influenced fluorescence values of enamel substrate. Conclusion: The thickness influenced fluorescence of enamel and all resin composite assessed showed fluorescence lower than natural dentin.


Objetivo: Este estudo avaliou o efeito da espessura de resinas compostas e substratos dentais (esmalte e dentina) sobre a fluorescência. Materiais e Métodos: Noventa incisivos bovinos foram utilizados, resultando em 45 discos de dentina e 45 discos de esmalte (6 mm de diâmetro e 0,5, 1 ou 1,5 mm mm de espessura). Noventa discos das resinas compostas Charisma, Filtek Z350 e IPS Empress Direct (para esmalte e dentina) foram confeccionados com a mesma dimensão. A fluorescência foi analisada por meio de espectrofluorímetro (RF-5301PC, Shimadzu Corp) com excitação de 365nm. Os dados foram submetidos ao teste ANOVA dois fatores e Teste de Tukey (α = 0,05). Resultados: O teste ANOVA dois fatores revelou diferenças significativas para todos os fatores, bem como para interação entre eles (p < 0,05). As amostras de dentina (1,5 mm) apresentaram alta fluorescência (128,33 A.U.), enquanto a resina composta Filtek Z350 (dentina - 1,0 mm) apresentou menor fluorescência (29,84 A.U.). A espessura influenciou os valores de fluorescência para o substrato esmalte. Conclusão: A espessura influenciou na fluorescência do esmalte e todas as resinas compostas avaliadas apresentaram uma fluorescência menor do que a dentina natural.


Subject(s)
Animals , Cattle , Dental Enamel , Dentin , Resins, Synthetic , Spectrometry, Fluorescence
18.
Braz. dent. j ; 26(5): 514-518, Oct. 2015. tab, graf
Article in English | LILACS | ID: lil-767634

ABSTRACT

Abstract: The aim of this study was to evaluate the effect of hydrogen peroxide whitening on fluorescence and color of bovine enamel and dentin. Twenty five dentin discs and 25 enamel discs, with 6 mm diameter and 1 mm thick, were obtained. Direct fluorescence (spectrofluorophotometry) and color (spectrophotometry) were assessed. After fluorescence and color baseline measurements, specimens were immersed in a 35% hydrogen peroxide (HP) solution for 1 h. This procedure was repeated after 7 days. Final fluorescence and color measurements were performed after the second immersion. Chemical characterization of 5 additional specimens was also performed. Data were submitted to repeated analysis of variance and Tukey´s test for fluorescence and unpaired t-test for color and chemical components (p<0.05). Fluorescence decreased significantly in dentin specimens after whitening. Enamel presented lower fluorescence than dentin at baseline, but this parameter did not decrease after whitening. Color changes were observed for both substrates, with significantly greater whitening effect in dentin (ΔE=10.37) (p<0.001). Whitening by hydrogen peroxide induced significant decrease in fluorescence of tooth dentin and promoted significant color changes in dentin and enamel with more accentuated outcomes in dentin.


Resumo: O objetivo deste estudo foi avaliar o efeito do clareamento com peróxido de hidrogênio na fluorescência e cor do esmalte e da dentina bovina. Vinte e cinco discos de dentina e 25 discos de esmalte, com 6 mm de diâmetro e 1 mm de espessura, foram obtidos. A fluorescência direta (Espectrofluorometria) e cor (espectrofotometria) foram avaliados. Depois da leitura inicial de cor e fluorescência, os espécimes foram imersos em solução de peróxido de hidrogénio a 35% (HP) durante 1 h. Este procedimento foi repetido após 7 dias. E as medições de fluorescência e de cor finais foram realizados após a segunda imersão. A caracterização química de 5 espécimes adicionais também foi realizada. Os dados foram submetidos à ANOVA de medidas repetidas e teste de Tukey para a fluorescência Teste e teste t não pareado para a cor e os componentes químicos (p<0,05). A fluorescência diminuiu significativamente nos espécimes de dentina após o clareamento. O esmalte apresentou fluorescência mais baixa do que a dentina na leitura inicial, mas esse parâmetro não diminuiu após o clareamento. Foram observadas alterações de cor para ambos os substratos, com significativamente maior efeito de clareamento em dentina (AE=10,37) (p<0,001). O clareamento com peróxido de hidrogênio provocou diminuição significativa na fluorescência da dentina e promoveu alterações de cor significativas na dentina e esmalte com resultados mais pronunciados em dentina.


Subject(s)
Animals , Cattle , Color , Dental Enamel , Dentin , Fluorescence , Hydrogen Peroxide/administration & dosage , Spectrometry, Fluorescence
19.
Indian J Biochem Biophys ; 2015 Feb; 52 (1): 107-110
Article in English | IMSEAR | ID: sea-157962

ABSTRACT

Autofluorescence exhibited by tissues often interferes with immunofluorescence. Using imaging and spectral analysis, we observed remarkable reduction of autofluorescence of formalin fixed paraffin embedded tissues irradiated with light prior to incubation with immunofluorescent dyes. The technique of photobleaching offers significant improvement in the quality and specificity of immunofluorescence. This has the potential for better techniques for disease diagnosis.


Subject(s)
Antibodies, Antinuclear/diagnosis , Fluorescent Antibody Technique/methods , Lung/cytology , /methods , Photobleaching , Spectrometry, Fluorescence/methods
20.
Arq. bras. cardiol ; 104(2): 120-127, 02/2015. tab, graf
Article in English | LILACS | ID: lil-741147

ABSTRACT

Background: Sudden cardiac death (SCD) is a sudden unexpected event, from a cardiac cause, that occurs in less than one hour after the symptoms onset, in a person without any previous condition that would seem fatal or who was seen without any symptoms 24 hours before found dead. Although it is a relatively frequent event, there are only few reliable data in underdeveloped countries. Objective: We aimed to describe the features of SCD in Ribeirão Preto, Brazil (600,000 residents) according to Coroners’ Office autopsy reports. Methods: We retrospectively reviewed 4501 autopsy reports between 2006 and 2010, to identify cases of SCD. Specific cause of death as well as demographic information, date, location and time of the event, comorbidities and whether cardiopulmonary resuscitation (CPR) was attempted were collected. Results: We identified 899 cases of SCD (20%); the rate was 30/100000 residents per year. The vast majority of cases of SCD involved a coronary artery disease (CAD) (64%) and occurred in men (67%), between the 6th and the 7th decades of life. Most events occurred during the morning in the home setting (53.3%) and CPR was attempted in almost half of victims (49.7%). The most prevalent comorbidity was systemic hypertension (57.3%). Chagas’ disease was present in 49 cases (5.5%). Conclusion: The majority of victims of SCD were men, in their sixties and seventies and the main cause of death was CAD. Chagas’ disease, an important public health problem in Latin America, was found in about 5.5% of the cases. .


Fundamento: Morte súbita cardíaca (MSC) é um evento súbito e inesperado, de causa cardiovascular, que ocorre em menos de uma hora após o início dos sintomas, em indivíduo sem qualquer condição clínica prévia potencialmente fatal ou assintomático nas últimas 24 horas antes do óbito, em caso de morte não testemunhada. Apesar de ser um evento relativamente frequente, há poucos dados confiáveis na literatura sobre países em desenvolvimento. Objetivo: Descrever as características da MSC em Ribeirão Preto (SP 600.000 habitantes) baseando-se nos relatórios de autopsias do Serviço de Verificação de Óbitos do Interior. Métodos: Foram revisados retrospectivamente 4.501 relatórios de autopsias entre 2006 e 2010, para identificar casos de MSC. Foram coletados dados como causa específica do óbito, características demográficas e comorbidades das vítimas, data, local e hora do evento, e se foram realizadas manobras de ressuscitação cardiopulmonar (RCP). Resultados: Foram identificados 899 casos de MSC (20%; razão 30/100.000 habitantes por ano). A principal causa de MSC foi doença arterial coronariana (DAC - 64%), acometendo homens (67%) entre a sexta e a sétima década de vida. A maior parte dos eventos ocorreu durante a manhã, no domicílio (53,3%), e a RCP foi realizada em quase metade das vítimas (49,7%). A comorbidade mais prevalente foi hipertensão arterial sistêmica (57,3%). Doença de Chagas foi detectada em 49 casos (5,5%). Conclusão: A maioria dos casos de MSC ocorreu por DAC em homens entre a sexta e a sétima década de vida. Doença de Chagas, um importante problema de saúde pública na América Latina, foi detectada em 5,5% dos casos. .


Subject(s)
Humans , Drug Evaluation, Preclinical/methods , Enzyme Inhibitors/pharmacology , Oligonucleotides/metabolism , Phosphoric Diester Hydrolases/metabolism , Spectrometry, Fluorescence/methods , Base Sequence , Cost-Benefit Analysis , Drug Evaluation, Preclinical/economics , High-Throughput Screening Assays , Kinetics , Mutation , Oligonucleotides/genetics , Phosphoric Diester Hydrolases/genetics , Spectrometry, Fluorescence/economics
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