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1.
Braz. J. Pharm. Sci. (Online) ; 57: e19023, 2021. tab, graf
Article in English | LILACS | ID: biblio-1345452

ABSTRACT

The ascorbyl methylsilanol pectinate (AMP) presents the same functional properties of ascorbic acid (AA). Besides antioxidant and depigmentant activity, the AMP presents silanol in its chemical structure. The aim of this work was to characterize and indentify the AMP alone and in cosmetic formulations. The following techniques were employed: Fourier Transform Infrared Spectrophotometry, particle size distributions, in vitro antioxidant activity with 2.2-diphenyl-1-picrylhydrazyl (DPPH) and Oxigen Radical Absorbance Capacity Assay and High Performace Liquid Chromatography (HPLC) (developed and validated method) for the active ingredient; Microscopy, HPLC and Normal Stability Assay (NSA) for the emulsions. Particle size distributions results showed that the average size of AMP was 1.0 µm and polydispersity index was 0.1. In DPPH assay AA and AMP were statistically the same. The value of ORAC obtained for AMP was 0.74 and for AA in the literature was 0.95. In the NSA the formulations were stable in conditions of 5.0 and 45.0 ± 2.0 ºC for 90 days. Adequate stability at ambient temperature out of reach of light was also observed. Thus, this works presented an acceptable method for quantification of AMP alone and in cosmetic formulations. AMP was an adequate choice for the incorporation in emulsions with antioxidant efficacy.


Subject(s)
Efficacy/classification , Emulsions/analysis , Fourier Analysis , Antioxidants/analysis , Ascorbic Acid/agonists , Spectrophotometry, Infrared/instrumentation , In Vitro Techniques/methods , Chromatography, High Pressure Liquid/instrumentation
2.
Gac. méd. Méx ; 156(4): 276-282, Jul.-Aug. 2020. graf
Article in English | LILACS | ID: biblio-1249911

ABSTRACT

Abstract Introduction: A drug-eluting coronary stent is being developed at the National Institute of Cardiology of Mexico for the treatment of ischemic heart disease. Objective: To establish the best animal model for the tests, to show the advances in the drug-eluting stent prototype, to assess two drugs’ antiproliferative activity and histological results. Method: Smooth muscle cell culture tests were performed in order to assess sirolimus and paclitaxel antiproliferative properties. The drugs were encapsulated inside the polymeric matrix of the stents. Rabbits and pigs were used as animal models. Results: Sirolimus and paclitaxel showed an inhibitory effect, which was higher for the latter. Infrared spectroscopy and light and optical microscopy showed that the drug/polymer layer properly adhered to the stent. At a four-week follow-up, both animal models showed satisfactory clinical evolution and adequate histological response, although the porcine model was shown to be more suitable for future protocols. Conclusions: Preliminary tests of the drug-eluting stent provided bases for the development of a study protocol with an adequate number of pigs and with clinical angiographic and histopathological three-month follow-up.


Resumen Introducción: En el Instituto Nacional de Cardiología de México se desarrolla una endoprótesis (stent) coronaria liberadora de fármacos para el tratamiento de la cardiopatía isquémica. Objetivo: Establecer el mejor modelo animal para las pruebas, mostrar los avances en el prototipo del stent liberador de fármacos, evaluar la actividad antiproliferativa de dos fármacos y los resultados histológicos. Método: Se realizaron cultivos de células de músculo liso para evaluar las propiedades antiproliferativas de sirolimus y paclitaxel. Los fármacos fueron encapsulados en el interior de la matriz polimérica de los stents. Se emplearon conejos y cerdos como modelos animales. Resultados: Sirolimus y paclitaxel mostraron efecto inhibitorio, mayor en el segundo. La espectroscopia infrarroja y la microscopia óptica y electrónica mostraron que la capa del polímero con el fármaco se adhería adecuadamente al stent. A las cuatro semanas de seguimiento, ambos modelos animales mostraron evolución clínica satisfactoria y adecuada respuesta histológica, si bien el modelo porcino resultó más conveniente para protocolos futuros. Conclusiones: Las pruebas preliminares del stent liberador de fármaco brindó bases para desarrollar el protocolo con un número adecuado en cerdos y con seguimiento clínico angiográfico e histopatológico a tres meses.


Subject(s)
Animals , Male , Female , Rabbits , Paclitaxel/administration & dosage , Sirolimus/administration & dosage , Drug-Eluting Stents , Prosthesis Design , Spectrophotometry, Infrared , Swine , Follow-Up Studies , Disease Models, Animal , Microscopy
3.
Medisan ; 24(3)mayo.-jun. 2020. ilus
Article in Spanish | LILACS, CUMED | ID: biblio-1125129

ABSTRACT

El análisis de los movimientos oculares permite diagnosticar enfermedades neurodegenerativas, neuropsiquiátricas y neurooftalmológicas, entre otras, que afectan el desempeño social del individuo. En este análisis ha tomado auge mundial el empleo de la videoculografía, por su simplicidad estructural, exactitud y factibilidad económica a largo plazo. Al respecto, el objetivo de la actual investigación fue desarrollar y evaluar un sistema de estimulación visual y registro de los movimientos oculares. El sistema en cuestión permitió obtener imágenes oculares con buena resolución (2 megapíxeles), nitidez y contraste que facilitaron su posterior procesamiento. De igual modo, las pruebas de estimulación mediante el uso de patrones sacádicos con amplitudes entre 30º y 60º a la frecuencia de 0,5 Hz permitieron obtener con suficiente calidad las imágenes registradas y verificar que los movimientos oculares del centro de la pupila siguen fielmente a dichos patrones.


The analysis of eye movements allows to diagnose neurodegenerative, neuropsychiatric and neuroophthalmologic diseases, among other that affect the individual social performance. In this analysis the use of videoculography is gaining in importance worldwide, due to its structural simplicity, precision and long term economic feasibility. In this respect, the objective of this investigation was to develop and evaluate a system of visual stimulation and record of the eye movements. The system in question allowed to obtain ocular images with good resolution (2 megapixels), clarity and contrast that facilitated its later processing. In a same way, the tests of stimulation by means of the sacadic patterns use with amplitudes between 30º and 60º to the 0,5Hz frequency allowed to obtain with enough quality the images recorded and to verify that the eye movements of the pupil center follow these patterns very closely.


Subject(s)
Image Processing, Computer-Assisted , Eye Movement Measurements , Spectrophotometry, Infrared
4.
Acta cir. bras ; 34(2): e201900203, 2019. tab, graf
Article in English | LILACS | ID: biblio-989053

ABSTRACT

Abstract Purpose: To analyze, histomorphologically, the influence of the geometry of nanostructured hydroxyapatite and alginate (HAn/Alg) composites in the initial phase of the bone repair. Methods: Fifteen rats were distributed to three groups: MiHA - bone defect filled with HAn/Alg microspheres; GrHA - bone defect filled with HAn/Alg granules; and DV - empty bone defect; evaluated after 15 days postoperatively. The experimental surgical model was the critical bone defect, ≅8.5 mm, in rat calvaria. After euthanasia the specimens were embedded in paraffin and stained with hematoxylin and eosin, picrosirius and Masson-Goldner's trichrome. Results: The histomorphologic analysis showed, in the MiHA, deposition of osteoid matrix within some microspheres and circumjacent to the others, near the bone edges. In GrHA, the deposition of this matrix was scarce inside and adjacent to the granules. In these two groups, chronic granulomatous inflammation was noted, more evident in GrHA. In the DV, it was observed bone neoformation restricted to the bone edges and formation of connective tissue with reduced thickness in relation to the bone edges, throughout the defect. Conclusion: The geometry of the biomaterials was determinant in the tissue response, since the microspheres showed more favorable to the bone regeneration in relation to the granules.


Subject(s)
Animals , Male , Rats , Biocompatible Materials/chemistry , Durapatite/chemistry , Nanostructures/chemistry , Alginates/chemistry , Spectrophotometry, Infrared , Biocompatible Materials/administration & dosage , Bone Regeneration/drug effects , Bone Regeneration/physiology , Rats, Wistar , Durapatite/administration & dosage , Nanostructures/administration & dosage , Alginates/administration & dosage
5.
Braz. oral res. (Online) ; 33: e008, 2019. tab, graf
Article in English | LILACS | ID: biblio-989480

ABSTRACT

Abstract The aim of this study was to evaluate the degree of conversion (DC) and the thermal stability of bulk-fill and conventional composite resins. Eleven composite resin samples were prepared to evaluate the DC, Vickers microhardness (VMH), mass and residue/particle loss, glass transition temperature (Tg), enthalpy, and linear coefficient of thermal expansion (CTE) using infrared spectroscopy (FTIR), microdurometer analyses, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dilatometry (DIL). The data were subjected to statistical analysis, with a significance level of 95%. DC and VMH were not influenced by the polymerized side of the sample, and statistical differences were recorded only among the materials. Decomposition temperature, melting, and mass and residue loss were dependent on the material and on the evaluation condition (polymerized and non-polymerized). Tg values were similar between the composites, without statistically significant difference, and CTE ranged from 10.5 to 37.1 (10-6/°C), with no statistical difference between the materials. There was a moderate negative correlation between CTE and the % of load particles, by weight. Most resins had a DC above that which is reported in the literature. TGA, Tg, and CTE analyses showed the thermal behavior of the evaluated composites, providing data for future research, assisting with the choice of material for direct or semidirect restorations, and helping choose the appropriate temperature for increasing the DC of such materials.


Subject(s)
Surface Properties , Materials Testing/methods , Composite Resins/chemistry , Dental Materials/chemistry , Spectrophotometry, Infrared , Temperature , Composite Resins/analysis , Dental Materials/analysis , Hardness
6.
Mem. Inst. Invest. Cienc. Salud (Impr.) ; 16(2): 94-99, Ago. 2018. tab, ilus
Article in Spanish | LILACS, BDNPAR | ID: biblio-998042

ABSTRACT

La cistinuria es una enfermedad genética que se engloba dentro de alteraciones congénitas del transporte de aminoácidos con formación de cálculos en las vías urinarias, si bien es poco frecuente se caracteriza por su elevada recurrencia. En este trabajo presentamos el caso de una paciente de 34 años, con antecedentes de haber perdido un riñón por episodios anteriores de litiasis y con múltiples recidivas que es diagnosticada mediante la detección de cistina por espectroscopía infrarroja como componente único de 96 fragmentos de cálculos removidos mediante nefrolitotomía percutánea. La paciente fue evaluada laboratorialmente mediante el perfil metabólico y la cristaluria. Las indicaciones de tratamiento específicas incluyeron la administración de agentes alcalinizantes, régimen nutricional, y entrenamiento para control de pH urinario. Es importante señalar la agresividad de la litiasis de cistina con las consecuencias que puede tener la calidad de vida del paciente, y por tanto la importancia de contar con capacidades instaladas a nivel país para el diagnóstico y seguimiento de litiasis genéticas como la causada por la cistinuria(AU)


Cystinuria is a genetic disease that is included among congenital defects of renal amino acids transport that causes urinary stone formation. Although it is rare, it is characterized by its high recurrence. We present the case of a 34-year-old patient that lost one of her kidney because of recurrent episodes of lithiasis, and that was diagnosed by the detection of cystine with infrared spectroscopy as the sole component of 96 stone fragments removed by percutaneous nephrolithotomy. The patient was evaluated by metabolic profile and crystalluria. The specific treatment indications included the administration of alkalinizing agents, nutritional regimen, and training for personal measurement of urinary pH. This case highlights the aggressiveness of cystine stones with the consequences that may have on the quality of the patient life, and therefore the importance of having installed proper diagnostic capacities at national level to detect and monitor treatment efficacy in genetic lithiasis such as cystinuria(AU)


Subject(s)
Humans , Female , Adult , Cystinuria/diagnosis , Spectrophotometry, Infrared , Kidney Calculi/diagnosis , Kidney Calculi/chemistry , Cystinuria/complications , Cystinuria/therapy , Nephrolithiasis/diagnosis , Nephrolithiasis/etiology , Nephrolithiasis/therapy
7.
Article in Chinese | WPRIM | ID: wpr-813185

ABSTRACT

To analyze types of urinary calculi and patients' clinical characteristics, and to explore the strategies for prevention and treatment of urinary calculi.
 Methods: A total of 1 849 patients with urinary calculi were treated in the Department of Urology, the Third Xiangya Hospital of Central South University. The components were analyzed by infrared spectroscopy. The relationship between stone composition and clinical parameters was analyzed according to the clinical characteristics of the patients.
 Results: The proportion of calcium oxalate stone or uric acid stone in male (84.1% or 7.7%) was higher than that in female (78.4% or 4.2%). The older patients were more likely to be diagnosed as uric acid stone. The proportions of uric acid stone in patients <18 years old, 18-<41 years old, 41-<66 years old, and ≥66 years old were 0.0%, 1.6%, 6.6%, and 12.4%, respectively. There was no significant difference in the proportion of stones in patients with different BMI. There were no significant difference in the stone composition between the patients with or without urinary tract infection, hypertension or diabetes. The proportion of uric acid stones in patients with acidic urine was higher than the other types. The proportion of uric acid stones in patients with elevated creatinine (12.1%) was higher than that in the patients with normal creatinine (4.5%).
 Conclusion: Elderly patients, or patients with high uric acid and renal insufficiency are more prone to uric acid stones. Regulation of urinary pH may be an important strategy for preventing and treating urinary calculi in Hunan Province.


Subject(s)
Adolescent , Adult , Age Factors , Aged , Body Mass Index , Calcium Oxalate , Creatinine , Urine , Female , Humans , Hydrogen-Ion Concentration , Kidney Calculi , Chemistry , Therapeutics , Male , Middle Aged , Sex Factors , Spectrophotometry, Infrared , Uric Acid , Urinary Calculi , Chemistry , Therapeutics , Urine
8.
Article in English | WPRIM | ID: wpr-812393

ABSTRACT

Analysis errors can occur in the desorbing process of ginkgo diterpene lactone meglumine injection (GDMI) by a conventional analysis method, due to several factors, such as easily crystallized samples, solvent volatility, time-consuming sample pre-processing, fixed method, and offline analysis. Based on risk management, near-infrared (NIR) and mid-infrared (MIR) spectroscopy techniques were introduced to solve the above problems with the advantage of timely analysis and non-destructive nature towards samples. The objective of the present study was to identify the feasibility of using NIR or MIR spectroscopy techniques to increase the analysis accuracy of samples from the desorbing process of GDMI. Quantitative models of NIR and MIR were established based on partial least square method and the performances were calculated. Compared to NIR model, MIR model showed greater accuracy and applicability for the analysis of the GDMI desorbing solutions. The relative errors of the concentrations of Ginkgolide A (GA) and Ginkgolide B (GB) were 2.40% and 2.89%, respectively, which were less than 5.00%. The research demonstrated the potential of the MIR spectroscopy technique for the rapid and non-destructive quantitative analysis of the concentrations of GA and GB.


Subject(s)
Chemistry, Pharmaceutical , Methods , Reference Standards , Drug Compounding , Reference Standards , Drugs, Chinese Herbal , Chemistry , Reference Standards , Ginkgolides , Chemistry , Reference Standards , Injections , Lactones , Least-Squares Analysis , Meglumine , Chemistry , Reference Standards , Reproducibility of Results , Risk Management , Spectrophotometry, Infrared , Reference Standards
9.
Article in English | WPRIM | ID: wpr-773604

ABSTRACT

Analysis errors can occur in the desorbing process of ginkgo diterpene lactone meglumine injection (GDMI) by a conventional analysis method, due to several factors, such as easily crystallized samples, solvent volatility, time-consuming sample pre-processing, fixed method, and offline analysis. Based on risk management, near-infrared (NIR) and mid-infrared (MIR) spectroscopy techniques were introduced to solve the above problems with the advantage of timely analysis and non-destructive nature towards samples. The objective of the present study was to identify the feasibility of using NIR or MIR spectroscopy techniques to increase the analysis accuracy of samples from the desorbing process of GDMI. Quantitative models of NIR and MIR were established based on partial least square method and the performances were calculated. Compared to NIR model, MIR model showed greater accuracy and applicability for the analysis of the GDMI desorbing solutions. The relative errors of the concentrations of Ginkgolide A (GA) and Ginkgolide B (GB) were 2.40% and 2.89%, respectively, which were less than 5.00%. The research demonstrated the potential of the MIR spectroscopy technique for the rapid and non-destructive quantitative analysis of the concentrations of GA and GB.


Subject(s)
Chemistry, Pharmaceutical , Methods , Reference Standards , Drug Compounding , Reference Standards , Drugs, Chinese Herbal , Chemistry , Reference Standards , Ginkgolides , Chemistry , Reference Standards , Injections , Lactones , Least-Squares Analysis , Meglumine , Chemistry , Reference Standards , Reproducibility of Results , Risk Management , Spectrophotometry, Infrared , Reference Standards
10.
Arq. bras. med. vet. zootec. (Online) ; 70(2): 597-605, mar.-abr. 2018. tab, graf
Article in Portuguese | LILACS, VETINDEX | ID: biblio-910879

ABSTRACT

O presente trabalho teve como objetivo validar a eficácia do método de espectroscopia de reflectância do infravermelho proximal (NIRS) em predizer o consumo e a digestibilidade da MS e nutrientes de dietas para cordeiros confinados, em comparação ao método convencional de laboratório. Amostras das dietas fornecidas, sobras e fezes de 40 cordeiros Santa Inês foram submetidas a ambos os métodos e analisadas quanto aos teores de MS, MM, FDN, FDA, PB e EE, para futuros cálculos do consumo e da digestibilidade. A maioria dos coeficientes de correlação do modelo ficou na faixa de 0,66 a 0,81, mostrando-se adequados para a predição quantitativa. Os maiores coeficientes foram observados para teores de PB das dietas (0,85) e sobras (0,87). Foram encontradas altas correlações entre os métodos na predição do consumo (média de 0,93) e digestibilidade (média de 0,90) das dietas. As correlações entre as variáveis obtidas pela predição do NIRS e pelo método convencional foram adequadas, demonstrando que, independentemente do método, os teores nutricionais das dietas, das sobras e das fezes podem ser utilizados para calcular o consumo e a digestibilidade da MS e dos nutrientes das dietas para cordeiros confinados, sendo recomendado o método NIRS pela precisão, pela rapidez e pelo baixo custo em relação ao método convencional.(AU)


This research was carried out to validate the effectiveness of the Near-IR spectroscopy method in predicting intake and digestibility of DM and nutrients of diets for feedlot lambs, in order to compare with the conventional laboratory method. Samples of diets, ort,s and feces of forty Santa Ines lambs were subjected to both methods and analyzed for DM, MM, NDF, ADF, CP, and EE for future calculations for intake and digestibility. Most of the model's correlation coefficient was in the range of 0.66 to 0.81, being suitable for quantitative prediction. Highest values for CP content of 0.85 (diets) and 0.87 (orts) were observed. There were high correlations between the methods to predicting intake (average values of 0.93) and digestibility (average values of 0.93). Correlations between the variables obtained by the prediction of NIRS and the conventional method were adequate, showing that regardless of the method, the nutritional content of diets, orts and feces can be used to calculate the intake and digestibility of DM and nutrients of lambs' diets. The Near-IR spectroscopy method is recommended for accuracy, speed and low cost compared to conventional method.(AU)


Subject(s)
Animals , Eating , Spectrophotometry, Infrared , Spectrum Analysis/trends , Sheep/metabolism
11.
An. acad. bras. ciênc ; 89(2): 1051-1059, Apr.-June 2017. tab, graf
Article in English | LILACS | ID: biblio-886697

ABSTRACT

ABSTRACT A series of arylamidines 3a-j was designed, synthesized and investigated for antimicrobial activity. Structures of the compounds were confirmed by IR, 1H-NMR and 13C-NMR and a 2D spectroscopic study was performed. A preliminary screening of the antimicrobial tests clearly showed that three out of ten arylamidines, viz, 3f, 3g and 3i, were effective against all the gram-negative bacteria: Klebsiella pneumoniae, Pseudomonas aeruginosa and Salmonella enteric; and against the yeast, candida albicans. Further, the Minimum Inhibitory Concentrations (MIC) against the bacteria and yeast were determined. All compounds 3a-d, 3f, 3g, 3i and 3j were also investigated for their low cytotoxic effects on tested cell lines. Compounds 3d and 3f were the most effective derivatives against HL-60 and HEp-2 cells, respectively, with IC50 value (2µg/mL), and low normal cells toxicity.


Subject(s)
Humans , Candida albicans/drug effects , Amidines/chemical synthesis , Amidines/pharmacology , Gram-Negative Bacteria/drug effects , Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/pharmacology , Spectrophotometry, Infrared , Tetrazolium Salts , Thiazoles , Materials Testing , Microbial Sensitivity Tests , Reproducibility of Results , Toxicity Tests , Cell Line, Tumor , Cell Proliferation/drug effects
12.
Article in English | WPRIM | ID: wpr-812037

ABSTRACT

Three new alkyl substituted anthraquinone derivatives, trivially named as symploquinones A-C (Compounds 1-3) were isolated from Symplocos racemosa. The structures of these compounds were determined on the basis of extensive spectroscopic analyses (UV, IR, Mass, H- and C-NMR, and two-dimensional (2D) NMR techniques). The resulting data were also compared with the reported literature. These compounds were then subjected to antibacterial or antibiofilm testing. Compounds 1 and 3 exhibited good antibacterial activity in the concentration range of 160-83 μg·mL against Streptococcus mutans, methicillin resistant Staphylococcus aureus and Proteus mirabilis. Both compounds were further screened for anti-biofilm activity, which revealed promising activities at sub-MIC concentrations. None of the compounds were found to be active against Klebsiella pneumoniae.


Subject(s)
Anthraquinones , Chemistry , Pharmacology , Anti-Bacterial Agents , Chemistry , Pharmacology , Biofilms , Ericales , Chemistry , Magnetic Resonance Spectroscopy , Mass Spectrometry , Methicillin-Resistant Staphylococcus aureus , Physiology , Microbial Sensitivity Tests , Proteus mirabilis , Physiology , Spectrophotometry, Infrared , Streptococcus mutans , Physiology
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.
São José dos Campos; s.n; 2017. 76 p. il., tab., graf..
Thesis in Portuguese | LILACS, BBO | ID: biblio-906707

ABSTRACT

O objetivo desse estudo in vitro foi avaliar a resistência adesiva, rugosidade superficial, ângulo de contato e o espectro infravermelho da zircônia, após diferentes tratamentos de superfície. Para isso, blocos (n=9) de zircônia Y-TZP (e.max ZirCad - Ivoclar, Schann, Liechtenstein) foram seccionados em 39 fatias (12 x 11x 3 mm) divididas em grupos de acordo com cada teste. Para resistência adesiva, 20 fatias foram divididos em: 2 grupos controle; JAT, jateamento com óxido de alumínio e sílica + primer (Monobond Plus - Ivoclar, Schann, Liechtenstein); HFP, condicionamento com ácido fluorídrico 10% + primer, e 3 experimentais: PL, plasma (Plasma Não Térmico de Superfície - modelo SAP); PLP, plasma + primer; HFPLP, ácido fluorídrico + plasma + primer. Cada fatia de zircônia foi cimentada (Multilink N - Ivoclair, Schann, Liechtenstein) a um bloco pré-polimerizado de resina composta. Após a cimentação os espécimes foram seccionados, e 48 palitos com área adesiva de 1 mm2 foram obtidos em cada grupo para o ensaio de microtração (µTBS). Quatro outras fatias foram submetidas à análise de rugosidade superficial e 12 fatias submetidas à análise do ângulo de contato, após os seguintes tratamentos de superfície: sem tratamento (AV), aplicação de ácido fluorídrico a 10% (AHF), aplicação de plasma (AP) e jateamento (AJ), sendo que para o ângulo de contato foram feitas medições imediatamente após o tratamento, após 12 e 24 horas. Os resultados foram submetidos à análise estatística Anova e teste de Tukey a 5% (p< 0,05). Os espectros das ligações químicas da superfície da zircônia foram determinados em 3 outras amostras após as seguintes condições: sem tratamento (AV), jateamento (JAT) e aplicação de ácido fluorídrico 10% seguido da aplicação do plasma (AHFP). Em termos de adesão, não houve diferença estatística significante entre os grupos JAT e HFPLP, porém esses 2 foram estatisticamente superiores ao grupos HFP, PL e PLP. O jateamento demonstrou aumentar significantemente a rugosidade superficial em relação aos demais grupos. O plasma demonstrou diminuir o ângulo de contato da superfície da zircônia imediatamente e ao longo de 48 horas(AU)


The purpose of this in vito study was to evaluate zirconia bond strength, surface roughness, contact angle and to mesure infrared spectrum after different surface treatments. Y-TZP zirconium (e.max ZirCAD - Ivoclair, Schann, Liechtenstein) blocks (n=9) were sliced into 36 discs (12 x 11 x 3 mm) and divided (n=4) into surface treatment groups as following: two control groups: JAT, airborneparticle abrasion and HFP, 10% hydrofluoric acid etching + primer (Monobond Plus - Ivoclair, Schann, Liechtenstein)application ,and three experimental groups: PL, non-thermal plasma (Surface Non-Thermal Plasma SAP model) application; PLP non-thermal plasma + primer application, and HFPLP, 10% hydrofluoric acid etching + non-thermal plasma + primer application. Each zirconia disk was cemented (Multilink N - Ivoclair, Schann, Liechtenstein) to a pre-polymerized resin block (Filtek Z350 - 3M, St Paul, MN, USA). After cementation the specimens were sectioned and 48 sticks with adhesive area of 1 mm2 obtained from each group for micro-tensile testing (µTBS). Four discs were submitted to surface roughness analysis and 12 discs to contact angle analysis, after the following surface treatments: no treatment (AV), 10% hydrofluoric acid etching (AHF), non-thermal plasma application (AP); and airborne- particle abrasion (AJ). The results were submitted to ANOVA and Tukey's test (p < 0.05). Zirconia surface chemical bonds spectrum was determined in infrared spectroscopy for three specimens after the conditions: no treatment; airborne- particle abrasion and hydrofluoric acid etching + non-thermal plasma application. The results showed no statistically significant differences between the groups JAT and HFPLP, but these two groups were statistically superior to HFP, PL and PLP. Airborne- particle abrasion resulted in a significant increase of surface roughness compared to the other groups. Non-thermal plasma was shown to decrease the contact angle of the surface, within 48 hours(AU)


Subject(s)
Humans , Adhesiveness , Spectrophotometry, Infrared/statistics & numerical data , Tensile Strength
15.
Braz. dent. j ; 27(6): 717-726, Nov.-Dec. 2016. graf
Article in English | LILACS | ID: biblio-828056

ABSTRACT

Abstract The aim of this study was to characterize the physico-chemical properties and bone repair after implantation of zinc-containing nanostructured porous hydroxyapatite scaffold (nZnHA) in rabbits' calvaria. nZnHA powder containing 2% wt/wt zinc and stoichiometric nanostructured porous hydroxyapatite (nHA - control group) were shaped into disc (8 mm) and calcined at 550 °C. Two surgical defects were created in the calvaria of six rabbits (nZnHA and nHA). After 12 weeks, the animals were euthanized and the grafted area was removed, fixed in 10% formalin with 0.1 M phosphate buffered saline and embedded in paraffin (n=10) for histomorphometric evaluation. In addition, one sample from each group (n=2) was embedded in methylmethacrylate for the SEM and EDS analyses. The thermal treatment transformed the nZnHA disc into a biphasic implant composed of Zn-containing HA and Zn-containing β-tricalcium phosphate (ZnHA/βZnTCP). The XRD patterns for the nHA disc were highly crystalline compared to the ZnHA disc. Histological analysis revealed that both materials were biologically compatible and promoted osteoconduction. X-ray fluorescence and MEV-EDS of nZnHA confirmed zinc in the samples. Histomorphometric evaluation revealed the presence of new bone formation in both frameworks but without statistically significant differences (p>0.05), based on the Wilcoxon test. The current study confirmed that both biomaterials improve bone repair, are biocompatible and osteoconductive, and that zinc (2wt%) did not increase the bone repair. Additional in vivo studies are required to investigate the effect of doping hydroxyapatite with a higher Zn concentration.


Resumo O objetivo deste estudo foi caracterizar físico-químicamente e avaliar o reparo ósseo de discos de hidroxiapatita porosa contendo zinco após a implantação em calvária de coelhos (nZnHA). O pó de nZnHA e o pó hidroxiapatita porosa estequiométrica nanoestruturada (controle - nHA) foram confeccionados em discos (8 mm) e calcinados a 550˚C. Dois defeitos cirúrgicos foram criados na calvária de seis coelhos para a implantação dos discos. Após 12 semanas, os animais foram eutanasiados e as áreas enxertadas foram removidas, fixadas em formol a 10% e embebidas em parafina (n=10) para avaliação histomorfométrica. Além disso, uma amostra de cada grupo (n=2) foi embebida em metilmetacrilato para análise de MEV e EDS. O tratamento térmico dos discos de nZnHA transformou-os em implantes bifásicos compostos por HA contendo Zinco e β fosfato tricálcico com Zinco (ZnHA/βZnTCP). Os discos de nHA, apresentaram-se altamente cristalinos e com baixa solubilidade quando comparados aos discos de ZnHA. A análise histológica revelou que ambos os materiais foram biologicamente compatíveis e promoveram a osteocondução. As análises de FRX e MEV-EDS confirmaram a presença do zinco nas amostras de nZnHA. A avaliação histomorfométrica revelou a presença de neoformação óssea em ambos os grupos, porém sem diferenças estatísticas entre eles, com base no teste de Wilcoxon (p>0,05). O presente estudo confirmou que ambos os biomateriais otimizaram o reparo ósseo, foram biocompatíveis e osseocondutivos e a presença do zinco não favoreceu o reparo ósseo. Estudos adicionais in vivo devem ser conduzidos a fim de investigar o efeito de maiores concentrações de zinco.


Subject(s)
Animals , Rabbits , Durapatite/analysis , Skull/chemistry , Zinc/analysis , Biocompatible Materials , Fluorescence , Microscopy, Electron, Scanning , Skull/anatomy & histology , Spectrophotometry, Infrared , X-Ray Diffraction
16.
Mem. Inst. Invest. Cienc. Salud (Impr.) ; 14(2): 106-109, ago. 2016. ilus
Article in Spanish | LILACS, BDNPAR | ID: biblio-869082

ABSTRACT

Ciertos fármacos que son excretados en orina, como los antibióticos, pueden formar cristales cuando la dosis empleadas son elevadas, la diuresis se encuentra disminuida o el pH de la orina es ácido. Los eventos de cristaluria medicamentosa son poco frecuentes y pueden ser cuadros asintomáticos e incluso originar fallos renales agudos. En este reporte se describen dos casos: una mujer de 26 años con cristaluria de ampicilina y una niña de 8 años con cristaluria de amoxicilina, registrados en el laboratorio de urgencias del Hospital Central del Instituto de Previsión Social. El análisis del sedimento fue realizado empleando microscopía óptica, luego los cristales fueron sometidos a microscopía de polarización y espectrofotometría infrarroja logrando la identificación exacta de la naturaleza química de los cristales. Este es el primer reporte de cristaluria medicamentosa del país y pone de manifiesto la importancia del trabajo colaborativo entre instituciones del estado.


Certain drugs that are excreted in the urine, including antibiotics, could induce theformation of crystals when the dose used is high, the diuresis is low or the pH of the urine isacid. The events of drug induced crystalluria are rare and could be asymptomatic or couldcause acute renal failure. In this report, we describe two cases: One of a 26-year-oldwoman with ampiciline crystalluria and a 8-year-old child with amoxiciline crystalluria, bothregistered at the Emergency Laboratory of the Central Hospital of the Instituto de PrevisionSocial. The analysis of the urinary sediment was made by conventional microscopy, andthen the crystals were studied by polarized light microscopy and infrared spectroscopyachieving the exact identification of the chemical nature of the crystals. This is the firstreport of drug induced crystalluria in the country and shows the importance of thecolaborative work between state institutions.


Subject(s)
Humans , Adult , Female , Microscopy, Polarization , Sediments/analysis , Spectrophotometry, Infrared , Urine
17.
Rev. paul. pediatr ; 33(1): 50-55, Jan-Mar/2015. tab
Article in English | LILACS | ID: lil-744704

ABSTRACT

OBJECTIVE: To investigate the association between physical inactivity and anthropometric measures in schoolchildren from Paranavaí-Parana, Brazil. METHODS: Cross-sectional survey, carried out in July and August 2013. Sample of 566 students (287 boys and 279 girls) from 6th to 9th grade, aged 10 to 14 years, from public and private schools of Paranavaí - PR, Southern Brazil. The variables analyzed were: time of weekly physical activity through a questionnaire (physical inactivity <300 minutes/week), body mass index (BMI) and waist circumference (WC). In the statistical analysis, the U Mann-Whitney and Student's t tests were used for comparison between genders. To identify factors associated with insufficient levels of physical activity, univariate and multivariate logistic regression analysis was applied and expressed in Odds ratio (OR) and 95% confidence interval (95%CI). RESULTS: There was an association between physical inactivity and anthropometric measurements for BMI (p<0.001) and WC (p<0.001), with a prevalence rate of 56.1% and 52.7% of inactive adolescents, respectively. In the multivariate analysis, there was significant association of physical inactivity and overweight (OR 1.8, 95%CI: 1.1-3.0) and with increased waist circumference (OR 2.8, 95%CI: 1.4-3.8). CONCLUSIONS: Inadequate levels of physical activity is a determining factor for overweight and abdominal adiposity. Accordingly, preventive measures should be taken, especially in schools, emphasizing the importance of exercise for body composition control and weight reduction. .


OBJETIVO: Investigar a associação entre a inatividade física e medidas antropométricas em escolares de Paranavaí, Paraná, Brasil. MÉTODOS: Pesquisa com delineamento transversal, feita em julho e agosto de 2013. Amostra composta por 566 escolares (287 meninos e 278 meninas), de 10 a 14 anos, do 6° ao 9° ano da rede pública e privada de Paranavaí (PR). As variáveis analisadas foram: tempo de atividade física semanal, por meio de questionário (inatividade física: < 300 min/semanal), índice de massa corporal (IMC) e circunferência de cintura (CC). Na análise estatística foram usados os testes U de Mann-Whitney e t de Student para comparar os sexos. Para verificar os fatores associados ao nível insuficiente de atividade física aplicou-se o modelo de regressão logística binária univariada e multivariada, expressa em odds ratio (OR), e intervalo de confiança de 95% (IC95%). RESULTADOS: Houve associação entre inatividade física e as medidas antropométricas para IMC (p<0,001) e CC (p<0,001), com prevalências de 56,1% e 52,7% de inativos, respectivamente. Na análise multivariada, foram observadas associações significativas de inatividade física nos alunos que apresentaram excesso de peso (OR 1,8; IC95%: 1,1-3,0) e circunferência de cintura aumentada (OR 2,2; IC95%: 1,4-3,8). CONCLUSÕES: Nível inadequado de atividade física é fator determinante no excesso de peso e na adiposidade abdominal. Nesse sentido, medidas preventivas devem ser tomadas, principalmente nas escolas, e enfatizar-se a importância do exercício físico no controle da composição corporal e redução do pesoe. .


Subject(s)
Fluorescence Resonance Energy Transfer , Lipid Bilayers/chemistry , Membrane Proteins/chemistry , Peptides/chemistry , Polycyclic Compounds/chemistry , Models, Molecular , Molecular Conformation , Spectrophotometry, Infrared
18.
Med. lab ; 21(3/4): 161-178, 2015. graf, tab, ilus
Article in Spanish | LILACS | ID: biblio-907768

ABSTRACT

Introducción: en aplicaciones biomédicas, la termografía infrarroja ha permitido visualizar el patrón de distribución de temperatura de la piel y el tejido subyacente, permitiendo diagnosticar problemas vasculares o nerviosos y, particularmente, trastornos en la termorregulación como el fenómeno de Raynaud y la intolerancia al frío. Sin embargo, las publicaciones no detallan el protocolo de adquisiciónde imágenes ni validan el mismo; factores determinantes para la calidad y relevancia de la informacióndiagnóstica obtenida. Objetivo: diseñar y validar un protocolo de adquisición de imágenes por termografía infrarroja para analizar la termorregulación en la mano. Materiales y métodos: Se diseñó un nuevo protocolo de adquisición de imágenes por termografía infrarroja utilizando un estímulofrío en la mano. Se analizaron estadísticamente regiones de interés de imágenes termográficas de 18 mediciones intrasujeto en un único sujeto y mediciones intersujeto en 17 individuos sanos. Resultados: En las mediciones intrasujeto e intersujeto se encontró que 10 minutos después del estímulo frío el porcentaje de recuperación de la temperatura fue cercano al 100%, excepto en un individuo en el cual, a pesar de no reportar enfermedades o lesiones previas, la punta de los dedos después del estímulo alcanzó apenas los 28 ºC. La prueba de fatiga en uno de los sujetos sanos mostró alteraciones en el proceso de termorregulación de la mano cuando el protocolo se repite en corto tiempo.


Introduction: in biomedical applications, infrared thermography has allowed to visualize the temperaturedistribution patterns of skin and underlying tissue, allowing the diagnosis of vascular or nervous disorders, particularly disturbances in the thermoregulation process as Raynaud’s phenomenon and cold intolerance. However, most papers not detailed the images acquisition protocol or its validation, being these two determining factors to the quality and relevance of the obtained diagnostic information.Objective: To design and validate an acquisition protocol of diagnostic imaging by infrared thermographyto analyze the thermoregulation process in hand. Material and methods: It was designed a new acquisition protocol of diagnostic imaging by infrared thermography using a cold stimulus in hand. It was statistically analyzed the regions of interest of thermographic images of 18 intrasubject measurements (in one individual) and intersubject measurements in 17 healthy individuals. Results: In the intrasubject and intersubject measurements, it found that 10 minutes after the cold stimulus the temperature measured was close to 100% of initial temperature, except for one of healthy subjects who, despite not report diseases or previous injuries, the temperature of the fingertips after stimulus barely reached 28 °C. The fatigue test in one healthy subject presents alterations in the thermoregulation process in hand when the protocol was repeated in a short time.


Subject(s)
Humans , Body Temperature Regulation , Spectrophotometry, Infrared , Thermography
19.
Article in Chinese | WPRIM | ID: wpr-304824

ABSTRACT

Crystal structures of chemical drugs has been being investigated widely. But few attention has been paid to polymorphs-phenomena of active ingredients from Traditional Chinese Medicine(TCM). Taking anhydrous dehydroandrographolide and hydrousprim-O-glucosylcimifugin as example, differences between TCM reference substances (RSs) with different crystal structures were discussed by using microscopy, melting point determination, differential thermal analysis (DTA) and infrared (IR) methods. The results showed that different crystal structures could lead to change of melting points, thermal behaviors and IR spectrum. It's indicated that polymorphs may be considered if different physicochemical properties were obtained when applying TCM RS. Differences of chemical properties of active ingredients from TCM with different crystal structures need further investigation.


Subject(s)
Crystallization , Differential Thermal Analysis , Methods , Reference Standards , Drugs, Chinese Herbal , Chemistry , Reference Standards , Medicine, Chinese Traditional , Molecular Structure , Reference Standards , Spectrophotometry, Infrared , Methods , Reference Standards , Transition Temperature
20.
Rev. Esc. Enferm. USP ; 48(spe): 59-66, 08/2014. tab
Article in English | LILACS, BDENF | ID: lil-731296

ABSTRACT

Objective To evaluate the use and records of the Child Health Handbook (CHH), especially growth and development. Method Cross-sectional study with 358 mother-child pairs registered in 12 Primary Health Centers (PHCs) of a small municipality. Mothers were interviewed at the PHC from February to April 2013 using a questionnaire. Data analysis was done using WHO Anthro software, Epi InfoTM and Stata. Results Fifty-three percent of the mothers were carrying the CHH at the time of the interview, similar to the proportion of mothers who were instructed to bring the CHH to health appointments. Annotations in the CHH during the visits were reported by 49%. The vaccination schedule was completed in 97% of the CHH, but only 9% and 8% of the CHH, respectively, contained growth charts and properly completed developmental milestones. Conclusion Low rates of use and unsatisfactory record-keeping in the CHH reinforce the need for investment in professional training and community awareness for the CHH to become an effective instrument of promotion of child health. .


Objetivo Evaluar el uso y llenado de la Libreta de Salud Infantil (LSI), especialmente el crecimiento y el desarrollo. Método Estudio transversal con 358 pares de madres e hijos matriculados en 12 Unidades Básicas de Salud (UBS) de una ciudad pequeña. Las madres fueron entrevistadas en el UBS desde febrero a abril 2013 mediante un cuestionario. Se utilizó Epi-info y software SPSS. Resultados 53% de las madres estaban llevando LSI durante la entrevista, proporción similar a las madres que recibieron instrucciones para llevar el LSI a la atención de la salud. Anotaciones en LSI durante las visitas se registraron en un 49%. Calendario de vacunas fue completa en el 97% de LSI, pero sólo el 9% y el 8% de LSI tenido, respectivamente, las curvas de crecimiento y desarrollos debidamente cumplimentados. Conclusión El uso y el relleno satisfactorio de LSI refuerzan la necesidad de inversión en la formación profesional y el acercamiento a la comunidad para la LSI se convierte efectivamente en un instrumento de promoción de la salud infantil.
 .


Objetivo Avaliar uso e preenchimento da Caderneta de Saúde da Criança (CSC), especialmente crescimento e desenvolvimento. Método Estudo transversal com 358 pares mãe-criança atendidos em 12 Unidades Básicas de Saúde (UBS) de município de pequeno porte. As mães foram entrevistadas nas UBS, de fevereiro a abril de 2013, com o uso de questionário. Utilizou-se softwares Epi-info e Stata. Resultados No momento da entrevista, 53% das mães portavam a CSC, proporção similar à de mães que referiram orientação para levar a CSC aos atendimentos de saúde. Anotações na CSC durante os atendimentos foram referidos por 49%. Esquema vacinal estava completo em 97% das CSC, mas apenas 9% e 8% das CSC tinham, respectivamente, gráficos de crescimento e desenvolvimento adequadamente preenchidos. Conclusão O uso e o preenchimento insatisfatório da CSC reforçam a necessidade de investimentos na capacitação dos profissionais e na sensibilização da comunidade para que a CSC se torne efetivamente um instrumento de promoção da saúde infantil. .


Subject(s)
Phenylacetates/chemistry , Carbon Tetrachloride , Deuterium Oxide , Deuterium/chemistry , Hydrogen Bonding , Spectrophotometry, Infrared , Temperature
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