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1.
Foods ; 13(6)2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38540884

RESUMEN

Asparagus production generates significant amounts of by-products during the summer and post-harvest growth period. By-products can be good sources of nutrients and phytochemicals. The interest in increasing the availability of proteins for human consumption has led to the use of new plant sources rich in proteins. The objective of this study was to use response surface methodology (RSM) to optimize the aqueous extraction process of proteins from asparagus leafy by-products, for the production of new protein ingredients. The optimum extraction condition was at pH 9, with 40 min of extraction at 50 °C, and the concentration was fixed at 5 g·L-1. The isolate obtained presented 90.48% protein with 43.47% protein yield. Amino acids such as alanine, proline, valine, leucine/isoleucine, asparagine, and phenylalanine were identified, and the antioxidant activity for 2,2 AZINO BIS (3-ethylbenzo thiazoline 6 sulfonic acid diammonium salt) was 145.76 equivalent to Trolox µmol.100g-1 and for DPPH 65.21 equivalent to Trolox µmol.100g-1. The product presented favorable technological properties (water absorption capacity 4.49 g·g-1 and oil absorption capacity 3.47 g·g-1) and the color tended towards dark green (L* 31.91, a* -1.01, b* -2.11). The protein isolate obtained through the extraction optimization process showed high potential to be used as a protein ingredient.

2.
J Mech Behav Biomed Mater ; 150: 106293, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38141362

RESUMEN

OBJECTIVES: to evaluate the quality and stability of adhesive interfaces established by self-etching adhesives on caries-affected primary dentin (CAD) treated with glutaraldehyde (GA) or silver diamine fluoride (SDF). METHODS: 42 primary molars were exposed to a microbiological caries-inducing protocol and divided into 6 groups according to the adhesive system (Clearfil SE - CL or FL Bond II - FL) and pretreatment (water, GA or SDF) applied on CAD. One tooth from each group was analyzed for surface modification using infrared spectroscopy. Crowns were restored with resin composite (n = 36) and cut into beams and slices. The beams were subjected to microtensile testing, Raman spectroscopy and SEM after 24 h and 6 months of storage. The slices were analyzed using Micro-Raman spectroscopy to determine the diffusion zone thickness (DZ) in each period. Data were analyzed by ANOVA and Tukey or Kruskal-Wallis and Dunn tests (α = 0.05%). RESULTS: SDF reduced the immediate bond strength for both adhesives. The control groups showed a decrease in BS after 6 months in artificial saliva. GA increased immediate DZ for FL, while SDF had the opposite effect on CL. GA decreased the DZ for FL at 6 months. There was a predominance of adhesive failures with areas of cohesive dentin fractures within control groups. SIGNIFICANCE: Modifications caused by dentin surface treatments may directly affect the performance of adhesive systems and the quality and stability of adhesive restorations.


Asunto(s)
Adhesivos , Recubrimiento Dental Adhesivo , Adhesivos/farmacología , Glutaral , Susceptibilidad a Caries Dentarias , Dentina , Resistencia a la Tracción , Resinas Compuestas/química , Recubrimientos Dentinarios/farmacología , Recubrimientos Dentinarios/química , Cementos de Resina/química , Ensayo de Materiales
3.
Cells ; 12(14)2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37508528

RESUMEN

The application of decellularized scaffolds for artificial tissue reconstruction has been an approach with great therapeutic potential in regenerative medicine. Recently, biomimetic ovarian tissue reconstruction was proposed to reestablish ovarian endocrine functions. Despite many decellularization methods proposed, there is no established protocol for whole ovaries by detergent perfusion that is able to preserve tissue macro and microstructure with higher efficiency. This generated biomaterial may have the potential to be applied for other purposes beyond reproduction and be translated to other areas in the tissue engineering field. Therefore, this study aimed to establish and standardize a protocol for porcine ovaries' decellularization based on detergent perfusion and ultrasonication to obtain functional whole-ovary scaffolds. For that, porcine ovaries (n = 5) were perfused with detergents (0.5% SDS and 1% Triton X-100) and submitted to an ultrasonication bath to produce acellular scaffolds. The decellularization efficiency was evaluated by DAPI staining and total genomic DNA quantification. ECM morphological evaluation was performed by histological, immunohistochemistry, and ultrastructural analyses. ECM physico-chemical composition was evaluated using FTIR and Raman spectroscopy. A cytocompatibility and cell adhesion assay using murine fibroblasts was performed. Results showed that the proposed method was able to remove cellular components efficiently. There was no significant ECM component loss in relation to native tissue, and the scaffolds were cytocompatible and allowed cell attachment. In conclusion, the proposed decellularization protocol produced whole-ovaries scaffolds with preserved ECM composition and great potential for application in tissue engineering.


Asunto(s)
Ovario , Andamios del Tejido , Femenino , Porcinos , Ratones , Animales , Andamios del Tejido/química , Detergentes/farmacología , Matriz Extracelular/metabolismo , Perfusión
4.
Plants (Basel) ; 11(24)2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36559526

RESUMEN

Green or purple lettuce varieties produce many secondary metabolites, such as chlorophylls, carotenoids, anthocyanins, flavonoids, and phenolic compounds, which is an emergent search in the field of biomolecule research. The main objective of this study was to use multivariate and machine learning algorithms on Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR)-based spectra to classify, predict, and categorize chemometric attributes. The cluster heatmap showed the highest efficiency in grouping similar lettuce varieties based on pigment profiles. The relationship among pigments was more significant than the absolute contents. Other results allow classification based on ATR-FTIR fingerprints of inflections associated with structural and chemical components present in lettuce, obtaining high accuracy and precision (>97%) by using principal component analysis and discriminant analysis (PCA-LDA)-associated linear LDA and SVM machine learning algorithms. In addition, PLSR models were capable of predicting Chla, Chlb, Chla+b, Car, AnC, Flv, and Phe contents, with R2P and RPDP values considered very good (0.81−0.88) for Car, Anc, and Flv and excellent (0.91−0.93) for Phe. According to the RPDP metric, the models were considered excellent (>2.10) for all variables estimated. Thus, this research shows the potential of machine learning solutions for ATR-FTIR spectroscopy analysis to classify, estimate, and characterize the biomolecules associated with secondary metabolites in lettuce.

5.
An Acad Bras Cienc ; 94(4): e20191372, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36449889

RESUMEN

This study aimed to evaluate the extraction of bioactive compounds from jaboticaba pomace, produce microcapsules by spray dryer technique, and characterize antioxidant compounds. A factorial experimental design was used in the extraction step. Maltodextrin (DE 10) was used as an encapsulating agent, in a ratio of 1: 1 (w/w), in the microencapsulation process. It was observed the increase of all bioactive compounds analyses comparing jaboticaba pomace with the extract. ATR-FTIR spectroscopy showed a vibrational stretching aromatic ring (1718 - 1731 cm-1) typical for anthocyanins. The Gaussian deconvolution presented extract peak area 7.56% higher than pomace. The encapsulating agent protected anthocyanins during the drying process. Microencapsulation of bioactive compounds from jaboticaba pomace can be useful for food applications whereas they are a rich source of antioxidant compounds. Moreover, the use of agro-industrial waste is promising linked to the use of clean technology as water as an antioxidant extractor.


Asunto(s)
Residuos Industriales , Myrtaceae , Antioxidantes , Antocianinas , Extractos Vegetales
6.
Int J Food Sci Nutr ; 73(7): 915-926, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35775312

RESUMEN

Trub, a brewing by-product, can be used as alternative ingredient for foods nutritional enrichment after its bitter compounds extraction. Study presents the optimisation of bitter compounds extraction from trub by Box-Behnken design, and use of debittered trub (DT) as new ingredient to enrich pasta. Bitterness extraction process was evaluated at different pH levels, time and extraction steps, and physical-chemical properties of DT (obtained under optimal conditions) were evaluated. Pasta was enriched with DT (5%, 10% and 15%) and its physical-chemical and quality properties were evaluated. Protein structure and chemical composition of trub were altered after process, also modifying its technological properties. Pasta with 10% DT increased in 33.51% protein content. Interaction of DT and wheat proteins resulted in a more compact structure, and DT water absorption capacity provided pasta texture changes. DT use improved pasta nutritional and quality properties, enabling trub valorisation and its use as vegetable proteins alternative source.


Asunto(s)
Harina , Triticum , Triticum/química , Harina/análisis , Culinaria , Mejoramiento de la Calidad , Proteínas de Vegetales Comestibles , Agua
7.
Clin Cosmet Investig Dent ; 14: 103-112, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35509813

RESUMEN

Background: The use of discolored teeth is required to test whitening products, and it is difficult to obtain them, given their scarcity. Objective: To present a technique for in vitro darkening of extracted teeth simulating pulpal necrosis discoloration. Materials and Methods: Hemolysates I and II from human blood were subjected or not to laser irradiation (442 nm) for 1 h. The concentration of oxyhemoglobin (O2Hb) was analyzed by ultraviolet/visible spectroscopy, and the conversion of O2Hb to methemoglobin (MetHb) by transmission spectroscopy was assessed immediately and after 3 and 40 days. For darkening evaluation, bovine incisors were divided into two groups (n = 25), and their pulp chambers were filled with hemolysate solution II (HSII) and hemolysate II solution + laser (HSII+L). After storage in artificial saliva for 40 days at 37°C, color changes were measured by a colorimeter and ΔE was compared with the NBS parameters. Data were analyzed using a mixed linear model (α=5%). Results: HSII+L presented the lowest O2Hb and higher MetHb. The conversion of O2Hb to MetHb in HSII+L was 42% higher than in HSII. Both groups were effective in darkening the teeth, according to the NBS. Darkening stabilized from day 35. HSII promoted a marked color difference. Conclusion: The proposed technique was effective in darkening the extracted teeth simulating necrosis discoloration for in vitro models.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 279: 121407, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35636138

RESUMEN

The search for gold-standard materials for bone regeneration is still a challenge in reconstruction surgery. The ratio between hydroxyapatite (HAp) and ß-tricalcium phosphate (ß-TCP) in biphasic calcium phosphate ceramics (BCPs) is one of the most important factors in osteoinduction promotion and controlled biodegradability, configurating what is currently considered as a possible gold standard material for bone substitution in reconstructive surgery. Exploring the natural genesis of the HAp and ß-TCP phases in fishbones during their postnatal growth, this study developed a biphasic bioceramic obtained from the calcination of Nile tilapia (Oreochromis niloticus) bones as a function of their ages. The natural genesis dynamics of the structural evolution of the ß-TCP and HAp phases were characterized by physicochemical methods, taking into account of the age of the fish and the material processing conditions. Thermal analysis (TGA / DTA) showed complete removal of the organic matter and transitions associated with the transformation of carbonated hydroxyapatite (CDHA) to HAp and ß-TCP phases. After calcination at 900 °C, the material was characterized by: X-ray diffraction (XRD) and refinement by the Rietveld method; Fourier Transform Infrared Spectroscopy with Attenuated Total Reflection (FTIR-ATR); Raman spectroscopy; Scanning Electron Microscopy (SEM) and Flame Atomic Absorption Spectroscopy (FAAS). The analysis allowed identification and quantitative estimate of the variations of the HAp and ß-TCP phases in the formation of the BCPs. The results showed that the decrease in ß-TCP against the increase in the HAp phases is symmetrical to the dynamics of the natural genesis of these phases, surprisingly maintaining the balanced phase proportion even when bones of young fishes were used. The microstructure analysis confirms the observed transformation. In addition, in vivo tests demonstrated the osteoinductive potential of BCP scaffolds implanted in an ectopic site, and their remarkable regenerative functionality, as bone graft, was demonstrated in alveolar bone after tooth extraction. MTT cytotoxicity assay for BCP samples for MC3T3-E1 pre-osteoblasts and L929 fibroblasts cells showed viability equal or higher than 100%. A logistic empirical model is presented to explain the three stages of HAp natural formation with fish age and it is also compared to the fish size evolution.


Asunto(s)
Fosfatos de Calcio , Durapatita , Animales , Regeneración Ósea , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Cerámica , Durapatita/química , Hidroxiapatitas/química
9.
Biomolecules ; 12(3)2022 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-35327575

RESUMEN

Fish bones are a natural calcium phosphate (CaP) sources used in biomaterials production for bone regeneration. CaP scaffolds can be enriched with other substances with biological activity to improve bone repair. This study aimed to evaluate the physicochemical properties and bone regeneration potential of biphasic calcium phosphate (BCP) scaffolds impregnated with free curcumin (BCP-CL) or complexed with ß-cyclodextrin (BCP-CD) compared to BCP scaffolds. Rietveld's refinement showed that BCP is composed of 57.2% of HAp and 42.8% of ß-TCP and the molar ratio of Ca/P corresponds to 1.59. The scaffolds presented porosity (macro and microporosity) of 57.21%. Apatite formation occurred on the BCP, BCP-CL, and BCP-CD surface, in vitro, in SBF. Micro-Raman technique showed a reduction in the dissolution rate of ß-TCP in the curcumin-impregnated scaffolds over time, and in vivo studies on critical-size defects, in rat calvaria, had no additional regenerative effect of BCP-CL and BCP-CD scaffolds, compared to BCP scaffolds. Despite this, the study showed that curcumin impregnation in BCP scaffolds prolongs the release of the ß-TCP phase, the BCP- phase with the higher osteoinductive potential, representing an advantage in tissue engineering.


Asunto(s)
Curcumina , beta-Ciclodextrinas , Animales , Regeneración Ósea , Curcumina/farmacología , Hidroxiapatitas , Ratas , Andamios del Tejido/química , beta-Ciclodextrinas/farmacología
10.
Clin Oral Investig ; 26(3): 2635-2643, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34697656

RESUMEN

OBJECTIVES: This study aims to evaluate the opalescence (OP) and color stability of composite resins over a period of 180 days and to compare composite resins' OP with enamel's OP. MATERIALS AND METHODS: Twenty human enamel specimens (5.0 × 0.3 mm) and 9 specimens (10.0 × 1.0 mm) of 10 colors of 4 different composite resins (3 M ESPE, FGM, Ivoclar-Vivadent, Miscerium) and one brand of adhesive (3 M ESPE) were made. The results were obtained by measuring the reflectance and transmittance spectra in the visible region. After baseline measurement, composites and adhesive were analyzed after 2, 7, 30, 60, 120, and 180 days. The Lab color coordinates were used in the calculations of the OP parameter and color differences in the CIELab and CIEDE2000 methods. The data were analyzed statistically. RESULTS: The materials tested showed variation and an increase in OP over time. The OP found for enamel was 18.06 ± 2.99, and some resins showed higher results. There was a strong correlation between the coordinate b*T and the OP over time. Enamel Plus was the only one material that presented no color changes during all periods in both color analyses. Filtek Z350 XT, AT, and BT did not show differences in any time when analyzed by CIELAB. CONCLUSIONS: The OP of most composite resins changed during the period of 180 days and was different from the OP of tooth enamel. In general, composites demonstrated small color changes over the period tested, being this characteristic material dependent. CLINICAL RELEVANCE: Natural teeth present different optical properties. Composite resins restorations should present properties similar to natural teeth and it is important that characteristics like color and opalescence remain stable over time.


Asunto(s)
Resinas Compuestas , Iridiscencia , Color , Esmalte Dental , Humanos , Estudios Longitudinales , Ensayo de Materiales
11.
Int J Dermatol ; 61(2): 191-198, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34235733

RESUMEN

BACKGROUND: Fusarium spp. has been considered as an onychomycosis agent, but little is known about the etiopathogenesis of fusarial onychomycosis; thus, the objective of this study was to characterize the fungal-nail interaction and the consequences of the nail infection process by Fusarium oxysporum using the human nail, in an ex vivo model. METHODS: The kinetic of biofilm production and infection by F. oxysporum using the nail as the only nutritional source were evaluated by scanning electron microscopy, number of culturable cells, metabolic activity, characterization of extracellular matrix, spectroscopy and histopathology analyses. RESULTS: After evaluating the biofilm kinetic over 7 days using different parameters and techniques, it was possible to characterize the Fusarium-nail interaction. CONCLUSIONS: This study is a part of a big project aiming to clarify the fusarial pathogenesis and contributes to proving F. oxysporum is able to adapt, grow, develop, and form a biofilm on healthy human nails, which are crucial steps for the invasion process.


Asunto(s)
Fusarium , Onicomicosis , Biopelículas , Humanos , Uñas
12.
Langmuir ; 37(10): 3202-3213, 2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33682407

RESUMEN

Phthalocyanine aluminum chloride (Pc) is a clinically viable photosensitizer (PS) to treat skin lesions worsened by microbial infections. However, this molecule presents a high self-aggregation tendency in the biological fluid, which is an in vivo direct administration obstacle. This study proposed the use of bioadhesive and thermoresponsive hydrogels comprising triblock-type Pluronic F127 and Carbopol 934P (FCarb) as drug delivery platforms of Pc (FCarbPc)-targeting topical administration. Carbopol 934P was used to increase the F127 hydrogel adhesion on the skin. Rheological analyses showed that the Pc presented a low effect on the hydrogel matrix, changing the gelation temperature from 27.2 ± 0.1 to 28.5 ± 0.9 °C once the Pc concentration increases from zero to 1 mmol L-1. The dermatological platform showed matrix erosion effects with the release of loaded Pc micelles. The permeation studies showed the excellent potential of the FCarb platform, which allowed the partition of the PS into deeper layers of the skin. The applicability of this dermatological platform in photodynamic therapy was evaluated by the generation of reactive species which was demonstrated by chemical photodynamic efficiency assays. The low effect on cell viability and proliferation in the dark was demonstrated by in vitro assays using L929 fibroblasts. The FCarbPc fostered the inhibition of Staphylococcus aureus strain, therefore demonstrating the platform's potential in the treatment of dermatological infections of microbial nature.


Asunto(s)
Fotoquimioterapia , Administración Tópica , Cloruro de Aluminio , Liberación de Fármacos , Hidrogeles , Indoles , Compuestos Organometálicos , Poloxámero
13.
Molecules ; 26(1)2021 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-33466379

RESUMEN

We evaluated a hydroalcoholic extract of Sapindus saponaria L. pericarps (ETHOSS), as a candidate to a topical antifungal medicine for onychomycosis. ETHOSS was produced by extracting the crushed fruits in ethanol. The saponin contents were identified and characterized by electrospray ionization mass spectrometry. We measured the in vitro antifungal activity against three dermatophyte fungi, isolated from onychomycosis: Trichophyton rubrum, T. mentagrophytes, and T. interdigitale, using broth microdilution tests. The minimum fungicide concentration of ETHOSS ranged from 195.31 to 781.25 µg/mL. The cytotoxicity of the crude extract was tested on the HeLa cell line, and its ability to permeate into healthy human nails by photoacoustic spectroscopy and Fourier transformation infrared spectrometer (FTIR) spectroscopy by attenuated total reflection. Besides its strong antifungal activity, ETHOSS showed low cytotoxicity in human cells. It was able to permeate and reach the full thickness of the nail in one hour, without the aid of facilitating vehicles, and remained there for at least 24 h. These results suggest that ETHOSS has great potential for treating onychomycosis.


Asunto(s)
Alcoholes/química , Antifúngicos/farmacología , Uñas/efectos de los fármacos , Extractos Vegetales/farmacología , Saponaria/química , Saponinas/farmacología , Adulto , Femenino , Humanos , Uñas/metabolismo
14.
J Esthet Restor Dent ; 33(6): 935-942, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33188585

RESUMEN

OBJECTIVE: To evaluate the translucency parameter (TP) and contrast ratio (CR) of different conventional restorative glass-ionomer cements (GICs). MATERIALS AND METHODS: Eighteen brands of GICs were evaluated. Five disks of each material were made following ISO 9917-1. The luminous reflectance and Central Bureau of the International Commission on Illumination parameters of disks were evaluated using a colorimeter, against backings of white and black, to obtain the translucent parameter and contrast ratio of different brands of glass-ionomer cements. The correlation between translucency parameter and contrast ratio was assessed with the Pearson correlation test. The translucent and contrast ratio parameters values were submitted to the one-way ANOVA and Tukey test for multiple comparisons (p < 0.05). RESULTS: There was a strong inverse relationship between CR and TP (r2  = 0.94, p < 0.001). The contrast ratio decreased as translucency increased. There were significant differences in TP and CR among brands (p < 0.001). CONLUSIONS: GICs exhibit different translucency and contrast ratio behavior. Some brands of GICs presented very low TP and this condition would be unacceptable for areas with esthetic demands. In addition, TP and CR showed a strong linear relationship. CLINICAL SIGNIFICANCE: The results found in this study demonstrated that the knowledge of the translucency and CR of different conventional restorative GICs is important in order to guide clinicians in the selection of restorative GICs for anterior teeth.


Asunto(s)
Cementos de Ionómero Vítreo , Ensayo de Materiales
15.
J Clin Exp Dent ; 12(12): e1117-e1123, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33282131

RESUMEN

BACKGROUND: It is known that bulk-fill have been widely studied and used by dentists in the clinic. However, the use of light-curing units that do not have the ability to adequately light-cure these materials at the appropriate depth can affect their clinical performance. The aim of this study was evaluating the influence of 5 different light curing units (LCUs) on the degree of conversion (DC) of a bulk-fill resin at depths of 0 to 4 mm and determined the effect of using 20s exposure and 40s. MATERIAL AND METHODS: Cylinders of composite were made in a stainless steel matrix (n=10). The specimens were exposed from the top surface using 5 LCUs: Valo® Cordless (VA); Radii Plus (RA); Emitter.D (EM), Biolux Plus (BI), Woodpecker® (WO). The emission wavelength and the power density was determined. After the photoactivation, the Raman vibrational modes were calculated taking as reference the peaks at 1,601 (aromatic bonds C=C) and 1,640 cm-1 (aliphatic bonds C=C). RESULTS: The largest difference in DC in 20s, comparing the values obtained in the first and last layer is for BI, with a variation from 61.24% to 53.86%. Comparing the LCUs, the last layer in 40s DC values are 57.40% (BI), 58.21% (WO), 58.97% (VA), 60.90% (RA) and 62.42% (EM). The higher the dose (J/cm²) and the close the λmax is to the maximum CQ absorption length (λmax ~ 470 nm) the better the DC value. CONCLUSIONS: There was a significant difference in the DC values between the LCUs with increasing depth of the bulk-fill increments. Results indicate significant differences in DC among the different LCUs as well as enhanced DC when using 40s exposure compared to 20s. It is suggested that for DC improvement using lower power photoactivator increase the exposure time the exposure time should be 20s to 40s. Key words:Polymerization, Composite Resins, Raman spectroscopy.

16.
J Clin Exp Dent ; 12(5): e461-e467, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32509228

RESUMEN

BACKGROUND: Some composite resins contain luminophorous agents in order to reproduce tooth fluorescence. The objective of this study was to compare the fluorescence spectra emitted by composite resins with those of human enamel and dentin, and their emission behaviour after a 90-day natural aging period. MATERIAL AND METHODS: Nine shades of the composite resins Z350XT/3M (XT), Opallis/FGM (OP) and Empress Direct/Ivoclar-Vivadent (ED) were analyzed. Five specimens (10.0 mm x 2.0mm) were fabricated for each shade. Enamel (5.0 mm x 0.30 mm) and dentin (5.0 mm x 1.0 mm) specimens were obtained from sound human third molars. Fluorescence spectra of human dentin and enamel as well as the composite specimens immediately after fabrication were measured at the excitation peaks of 375, 395 and 410 nm. To assess composite resin fluorescence intensity changes over time, measurements were conducted after 30, 60 and 90 days, at 395 nm. Differences in fluorescence intensity over time were analyzed with ANOVA and Tukey's test (p<0.05). RESULTS: Fluorescence spectra baseline values of composites demonstrated no differences in intensity among the excitation peaks tested, with maximum emission found at the peak of 450 nm. Enamel and dentin spectra varied with different excitations, and the greater the excitation, the longer the wavelength in comparison to composite resins. After 90 days, XT presented an increase in fluorescence intensity, while OP and ED showed a reduction when compared with baseline values. CONCLUSIONS: Fluorescence intensity of composite resins changed during the period analyzed, with an emission behavior different from that of human enamel and dentin. The main changes occurred in the first 30 days. Key words:Composite resins, dental materials, fluorescence, fluorescence spectrometry.

17.
J Adhes Dent ; 22(3): 297-309, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32435770

RESUMEN

PURPOSE: To evaluate the remineralization effects of Bioglass 45S5 (BAG) on dentin composition, adhesive-dentin bond strength, as well as interface and diffusion zone thickness. MATERIALS AND METHODS: Dentin specimens were assigned to a control group (CG), in which the adhesive was applied following the manufacturer's instructions, and a remineralized group (RG), in which remineralization treatment was carried out by rubbing a remineralization solution (0.015 g of BAG with 1.35 ml of distilled water) on the etched dentin surface for 30 s before applying the adhesive. For bioactive analysis (n = 10), control and remineralized dentin were investigated using micro-Raman spectroscopy (mRS) and scanning electron microscopy (SEM). Stick specimens prepared with a three-step etch-and-rinse adhesive were submitted to a microtensile bond strength (µTBS) test (n = 10) after 24 h (24 h) and eight months (8 m). Micro-RS 3D-maps (n = 10) characterized the adhesive-dentin interface composition and diffusion zone thickness, and SEM images (n = 10) evaluated interface thickness. Data were analyzed using Student's t-test or two-way ANOVA and Tukey-Kramer's post-hoc test (α = 0.05). RESULTS: Remineralization treatment increased the mineral content of dentin. Mean µTBSs were statistically different at 24 h, with RG higher than CG; however, this difference was not significant at 8 m. When the adhesive was applied on remineralized dentin, its penetration was reduced, its physical interaction with phosphate was improved, and its degree of conversion increased. The diffusion zone in the CG did not differ from that of the RG, and interface thickness values of the CG did not differ from that of the RG. CONCLUSION: Remineralization treatment promoted mineral growth on the dentin surface, improved the interaction of dentin with adhesive monomers, and consequently resulted in higher immediate bond strengths.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos Dentales , Dentina , Recubrimientos Dentinarios , Humanos , Resistencia a la Tracción
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 234: 118246, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-32179464

RESUMEN

The secondary metabolites produced by Fusarium can cause disease and death when consumed and produce biological responses even in the absence of the microorganism. The IL-6, TNF-α and TGF-ß1 cytokines immune reactivity was associated with histopathological and physico-chemical changes in skin of immune competent rats after administration of Fusarium oxysporum crude extract. Rats were intradermally injected with 50 µl of 0.5 mg/ml crude extract and were euthanized at 3, 6, 12 and 24 h after injection. The inflammatory response was quantified by enzyme myeloperoxidase activity and by immunohistochemical method to detect the IL-6, TNF-α and TGF-ß1. Physico-chemical analysis was performed using FT-Raman Spectroscopy. The inflammatory response was most intense at 6 and 12 h after crude extract administration and the most significant histopathological changes were observed in the dermis. Myeloperoxidase activity was intense from 3 to 24 h after injection. The immunostaining of pro-inflammatory cytokines IL-6 and TNF-α peaked at 6 h. Immunostaining for TGF-ß1 was highest at 12 and 24 h. FT-Raman spectral analysis showed both, the most intense Fusarium interaction with the skin at 6 h, as revealed by the changes in the stretching of -CH bands (3100-2800 cm-1) in the dermis, and skin recovery trending after 12 h after crude extract injection. The results showed that secondary metabolites stimulated histopathologic changes and inflammatory responses even in the absence of the fungus, increasing myeloperoxidase activity and pro-inflammatory cytokine expression besides promoting physico-chemical changes.


Asunto(s)
Fusarium/metabolismo , Metaboloma , Piel/inmunología , Piel/microbiología , Espectrometría Raman , Animales , Inyecciones Intradérmicas , Interleucina-6/metabolismo , Masculino , Análisis de Componente Principal , Ratas Wistar , Tejido Subcutáneo/patología , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
19.
J Photochem Photobiol B ; 203: 111745, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31931381

RESUMEN

Light affects many aspects of cell development. Tomato seedlings growing at different light qualities (white, blue, green, red, far-red) and in the dark displayed alterations in cell wall structure and composition. A strong and negative correlation was found between cell wall thickness and hypocotyl growth. Cell walls was thicker under blue and white lights and thinner under far-red light and in the dark, while intermediate values was observed for red or green lights. Additionally, the inside layer surface of cell wall presented random deposited microfibrillae angles under far-red light and in the dark. However, longitudinal transmission electron microscopy indicates a high frequency of microfibrils close to parallels related to the elongation axis in the outer layer. This was confirmed by ultra-high resolution small angle X-ray scattering. These data suggest that cellulose microfibrils would be passively reoriented in the longitudinal direction. As the cell expands, the most recently deposited layers (inside) behave differentially oriented compared to older (outer) layers in the dark or under FR lights, agreeing with the multinet growth hypothesis. High Ca and pectin levels were found in the cell wall of seedlings growing under blue and white light, also contributing to the low extensibility of the cell wall. Low Ca and pectin contents were found in the dark and under far-red light. Auxins marginally stimulated growth in thin cell wall circumstances. Hypocotyl growth was stimulated by gibberellins under blue light.


Asunto(s)
Pared Celular/fisiología , Luz , Solanum lycopersicum/fisiología , Antocianinas/análisis , Calcio/metabolismo , Pared Celular/química , Cromatografía Líquida de Alta Presión , Solanum lycopersicum/crecimiento & desarrollo , Solanum lycopersicum/efectos de la radiación , Microfibrillas/química , Microscopía Electrónica de Transmisión , Pectinas/metabolismo , Reguladores del Crecimiento de las Plantas/análisis , Reguladores del Crecimiento de las Plantas/metabolismo , Análisis de Componente Principal , Dispersión del Ángulo Pequeño , Plantones/crecimiento & desarrollo , Plantones/fisiología , Plantones/efectos de la radiación , Difracción de Rayos X
20.
Nat Prod Res ; 34(16): 2341-2345, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30584785

RESUMEN

Fish oil (FO) is a natural source of omega-3 fatty acids, with well-established beneficial effects in inflammatory diseases when FO is orally administered. This study investigated the effects of a topically applied FO preparation (FOP) on phenol-induced ear edema and evaluated the percutaneous penetration of FOP in ear tissue. After applying phenol, groups of mice received FOP on the ear. After 1 h, ear tissue was collected to determine the percent inhibition of edema, myeloperoxidase activity, and to perform photoacoustic spectroscopy (PAS). Treatment with FOP did not reduce edema, but reduced myeloperoxidase activity. The FOP decreased the area of bands that characterize inflamed tissue and penetrated into the tissue. These results indicated an inhibitory effect of FOP on leukocyte recruitment in phenol-induced ear edema. These data support the applicability of PAS as a non-destructive method for evaluating the inflammatory response, percutaneous penetration and antiinflammatory activity of compounds.


Asunto(s)
Aceites de Pescado/farmacología , Inflamación/tratamiento farmacológico , Leucocitos/efectos de los fármacos , Administración Tópica , Animales , Modelos Animales de Enfermedad , Oído/patología , Edema/inducido químicamente , Edema/tratamiento farmacológico , Aceites de Pescado/administración & dosificación , Aceites de Pescado/uso terapéutico , Inflamación/inducido químicamente , Leucocitos/citología , Ratones , Peroxidasa/antagonistas & inhibidores , Fenol/efectos adversos , Técnicas Fotoacústicas/métodos , Piel/patología , Absorción Cutánea
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