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1.
Artigo em Inglês | LILACS, BBO | ID: biblio-1287496

RESUMO

Abstract Objective: To evaluate the reliability of infrared (IR) thermal camera connected to smartphones, already used in medicine for diagnostic purposes, as an easy tool for access screening to pediatric dentistry services. Material and Methods: After the preventive telephone triage, thirty orthodontic patients (7-13 years) underwent temperature measurement in the office with two no-contact IR devices: forehead digital thermometer and thermal-camera connected to a smartphone (reference areas: forehead, inner canthi, ears). Measurements were compared and differences were statistically investigated with T student's test (p<0.01). Results: Forehead digital thermometer temperatures were superimposable to those recorded in ear areas and inner canthi with the thermal camera connected to a smartphone. Differences were not statistically significant even in comparison between the sexes. Forehead temperature values detected with a thermal camera are lower than those detected with a digital forehead thermometer. Conclusion: Thermal camera on a smartphone could be reliable in measuring body temperature. Mobile thermographic values of ears and inner canthi areas can be used as an alternative to forehead digital thermometer measurements. Further applications in pediatric dentistry of thermography on smartphones should be examined.


Assuntos
Humanos , Masculino , Feminino , Criança , Temperatura Corporal , Termografia/instrumentação , Odontopediatria , Análise Diferencial Térmica/instrumentação , COVID-19 , Interpretação Estatística de Dados , Smartphone , Itália/epidemiologia
2.
Braz. arch. biol. technol ; 62: e19180579, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055409

RESUMO

Abstract Ginger and white yam starches were investigated and compared with maize starch. Proximal composition, thermogravimetry, differential scanning calorimetry, microscopy, colourimetry, X-ray powder diffractometry and pasting profile were analysed. The unconventional starches presented higher protein and ash contents than the maize starch, that had the highest thermal stability. Higher gelatinisation temperatures were reported for ginger starch, and the enthalpy of the unconventional starches were similar. The maize starch presented the lowest gelatinisation values. For the corn starch the granules were polygonal and smaller than the unconventional starches, and oval shapes and larger diameters were found for the ginger and yam starches. The unconventional starches presented less brightness and a greater tendency to red and yellow. The maize and ginger starches had A-type diffraction patterns, while the white yam starch had a C-type pattern. The highest relative crystallinity was observed for the ginger starch and there were small differences between the yam and maize starches. Higher peak viscosity and final viscosity and lower pasting temperature were observed for the yam starch. Ginger starch showed the highest shear and stability of heating glue, so may be used in products processed under high temperatures; and yam starch can be used in acidic foods that require high viscosities.


Assuntos
Zingiber officinale/química , Colocasia/química , Amidos e Féculas , Termogravimetria/instrumentação , Análise Diferencial Térmica/instrumentação , Microscopia/instrumentação
3.
São Paulo; s.n; s.n; 2016. 211 p. ilus, tab, graf.
Tese em Português | LILACS | ID: biblio-883757

RESUMO

A nistatina (NYS) é o fármaco de primeira escolha no tratamento da candidíase oral, que frequentemente acomete mais os indivíduos imunocomprometidos e pacientes com outras desordens (diabetes não tratada, neoplasias, imunodeficiências). No mercado brasileiro, a NYS é encontrada na forma de suspensão oral aquosa, onde o procedimento para sua administração consiste em bochechar o medicamento. Apesar de haver a indicação de que se mantenha o contato direto entre fármaco e a mucosa oral, na qual se encontra a Candida spp., o que aumentaria expressivamente o sucesso terapêutico, a suspensão não apresenta tal propriedade. Assim, a NYS que é fármaco com ação efetiva contra a candidíase oral, é considerada pertencente à Classe IV do Sistema de Classificação Biofarmacêutica, ou seja, apresenta baixa solubilidade e baixa permeabilidade. A baixa solubilidade pode comprometer sua disponibilidade na cavidade oral, e consequentemente, sua ação farmacológica. Diante desse quadro, o objetivo do presente trabalho foi o desenvolvimento de dispersões sólidas de NYS para o tratamento da candidíase oral, e sua posterior incorporação em gel mucoadesivo oral, favorecendo a formulação no local de ação. As dispersões sólidas são sistemas farmacêuticos, onde um fármaco pouco solúvel em água encontra-se dispersado em um carreador, no estado sólido. Os carreadores normalmente são hidrofílicos, o que permite que esses sistemas sejam empregados para aumentar a solubilidade aquosa do fármaco. Assim, foram desenvolvidas as dispersões sólidas de NYS, pelo método de eliminação do solvente, empregando como carreadores, lactose, HPMC, poloxamer 407 e poloxamer 188. Essas foram submetidas à caracterização por análise térmica, usando os ensaios de calorimetria exploratória diferencial (DSC) e termogravimetria/termogravimetria derivada (TG/DTG). Dentre essas dispersões sólidas, aquelas que se mostraram com comportamento térmico sugerindo a formação de um novo "sistema", foram analisadas por meio de ensaio de solubilidade. Dessa forma, a formulação NYS DS G2 (49) se destacou, pois apresentou maior solubilidade em água (4,484 mg/mL); em pH 5,5 (4,249 mg/mL) e em pH 7,0 (4,293 mg/mL), ou seja, houve um aumento de 1,426 vezes em água; 4,227 vezes em pH 5,5; e 2,743 vezes em pH 7,0. Essa formulação foi, por fim avaliada por difração de raio-X e espectroscopia de infravermelho com transformada de Fourier, técnicas que corroboraram com a análise térmica quanto à indicação de formação da dispersão sólida. Por sua vez, essa dispersão sólida foi incorporada em 4 bases de géis mucoadesivos de carbopol ® 934 PNF, alterando apenas a concentração do polímero (0,5; 1,0; 1,5; 2,0 %p/p). Foi observado que a liberação de NYS DS G2 (49) foi superior, quando comparada à liberação de NYS MP a partir do gel, e através do ensaio de mucoadesão, percebeu-se que os géis desenvolvidos apresentaram propriedades mucoadesivas compatíveis com relatos na literatura, independentemente da quantidade de carbopol ® empregada. As características reológicas foram distintas, e foi observado que as formulações Gel A e Gel B, que possuem menor quantidade de polímero, tiverem um indicativo de comportamento de fluido newtoniano, diferente dos demais, o que pode não ser desejado para esse tipo de forma farmacêutica tópica e semi-sólida. Ao final desse trabalho, pode-se concluir que foi possível desenvolver um sistema farmacêutico na forma de dispersão sólida com maior solubilidade que a NYS pura, e sua incorporação em uma forma farmacêutica mucoadesiva, e que a liberação da NYS na forma DS foi muito superior que o fármaco na forma "convencional", o que permite que a NYS esteja mais disponível na cavidade oral, e também junto à mucosa bucal, o que levaria a efeito farmacológico mais efetivo do antifúngico


Nystatin (NYS) is the drug of first choice in the treatment of oral candidiasis that most often affect immunocompromised individuals, and patients with other disorders. In the Brazilian market, NYS is found in the form of aqueous oral suspension, a medication used in the form of mouthwash. Although there is an indication to maintain direct contact between the drug and the oral mucosa, where Candida spp. is found, as well as where therapeutic success would significantly be increased, the suspension has no such property. Thus, the NYS is an effective drug against oral candidiasis, and belongs to Class IV of the Biopharmaceutical Classification System, it has low solubility and low permeability. The low solubility can compromise its availability in the oral cavity, and consequently, its pharmacological action. Given this situation, the objective of this work was the development of solid dispersions of NYS for the treatment of oral candidiasis, and its subsequent incorporation into oral mucoadhesive gel, in order to facilitate its action. Solid dispersions are pharmaceutical systems, in which a solid drug poorly soluble in water is dispersed in a carrier. These carriers are usually hydrophilic, and this allows the systems to be employed in order to increase the aqueous solubility of the drug. Thus, the solid NYS dispersions were developed by the solvent evaporation method, employing lactose, HPMC, poloxamer 407 and poloxamer 188 as carrier. These samples were subjected to characterization by thermal analysis, using differential scanning calorimetry (DSC) and thermogravimetry / derivative thermogravimetry (TG / DTG). Among these solid dispersions, those samples which showed a specific thermal behavior suggesting the formation of new "system" were analyzed by solubility test. Thus, the NYS DS G2 formulation (49) stood out, once it showed greater solubility in water (4.484 mg/mL); at pH 5.5 (4.249 mg/mL) and pH 7.0 (4.293 mg/mL), in other words, an increase of 1,426 times in water; 4,227 times at pH 5.5; and 2,743 times at pH 7.0. This formulation was finally evaluated by X-ray diffraction, infrared spectroscopy with Fourier transform, techniques that corroborate the thermal analysis, indicating the formation of the solid dispersion. On the other hand, this solid dispersion was incorporated into 4 Carbopol ® 934 PNF mucoadhesive gels, with a variation of the polymer concentration. It was observed that NYS is improved of delivery from the gels, employing mucoadhesion test, and was also observed that the gels have mucoadhesive properties consistent with reports in the literature. However, the rheological characteristics are different, and it was observed that the Gel A and Gel B formulations, which has a lower amount of polymer behaved as a Newtonian fluid, which may not be desired for this type of topical gel. As conclusion, it was possible to develop a pharmaceutical system in the form of solid dispersion with greater solubility than the pure NYS, and their incorporation in a mucoadhesive dosage form and the release of NYS as DS was far superior wherein the drug in the "conventional" manner, which allows the NYS is longer available in the oral cavity, and also adjacent to the buccal mucosa, leading to more effective pharmacological effect of the antifungal agent


Assuntos
Candidíase Bucal/tratamento farmacológico , Nistatina/análise , Solubilidade , Termogravimetria/métodos , Varredura Diferencial de Calorimetria/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/instrumentação , Análise Diferencial Térmica/instrumentação
4.
São Paulo; s.n; s.n; fev. 2015. 96 p. tab, graf, ilus.
Tese em Português | LILACS | ID: biblio-836741

RESUMO

A hipertensão é uma doença crônica não transmissível e mais freqüente na população sendo o principal fator de risco para complicações cardiovasculares, tais como acidente vascular cerebral e infarto agudo do miocárdio. Na presente pesquisa estão sendo estudados os fármacos utilizados no tratamento da hipertensão mais especificamente, os bloqueadores do canal de cálcio do grupo diidropiridínicos: besilato de anlodipino, nifedipino e nimodipino. O objetivo desse trabalho foi verificar a estabilidade intrínseca dos fármacos besilato de anlodipino, nifedipino e nimodipino, para isto foram utilizadas as seguintes técnicas: testes indicativos de estabilidade utilizando as técnicas de espectrofotometria na região do Ultravioleta/Visível (UV/VIS) e Cromatografia em fase Líquida de Alta Eficiência (CLAE). Termogravimetria/ Termogravimetria Derivada (TG/DTG), Calorimetria Exploratória Diferencial (DSC), Difração de Raios X (DRX), Espectroscopia de absorção na região do Infravermelho com Transformada de Fourier (FTIR) e Microscopia Eletrônica de Varredura (MEV). Para o fármaco besilato de anlodipino (AB) pelo método de degradação forçada, analisado por espectrofotometria no UV/VIS, as condições para a análise espectrofotométrica foram metanol e água a uma proporção de (5:45 v/v) e a segunda diluição com água. A leitura foi efetuada a 364,4nm. A linearidade foi estabelecida na faixa de 40,0-65,0 µg/mL e o coeficiente de correlação foi (r) 0,9992. O método cromatográfico, mostrou o diferente comportamento das substâncias nifedipino e nimodipino diante dos meios básicos, ácido, neutro e oxidativo. As condições para a substância nifedipino foram coluna LiChrospher®100 RP-18 (5µm) Merck® fase móvel constituída por metanol e água (45:55v/v), fluxo 1.0 mL/min, tempo de retenção 5,1min, detecção UV a 234nm e vazão de 1.0 mL/min. Foi obtida uma linearidade no intervalo de 5.0-55.0 µg/mL coeficiente de correlação (r) =0,9964. E para a substância nimodipino foram coluna LiChrospher®100 RP-18 (5µm) Merck® fase móvel constituída por acetonitrila e água (55:45v/v), fluxo 1.0mL/min, tempo de retenção 5,8 min, detecção UV a 235 nm e vazão de 1.0mL/min. Foi obtida uma linearidade no intervalo de 5.0-55.0 µg/mL coeficiente de correlação (r) =0,9964. Os resultados obtidos das curvas TG/DTG e DSC mostraram o perfil da decomposição térmica das substâncias estudadas pela Calorimetria Exploratória Diferencial. A análise dos resultados de DRX e DSC mostraram que não há evidências de polimorfismo nessas substâncias. No entanto nas análises de Espectroscopia de absorção na região do infravermelho com Transformada de Fourier (FTIR) não foram encontradas diferenças significativas na matéria-prima e no padrão de referência. As análises de MEV permitiram observar a cristalinidade das substâncias estudadas


Hypertension is the most frequent non-communicable chronic disease in the population being the main factor of risk for cardiovascular complications, such as stroke and acute myocardial infarction. In this work, active pharmaceutical ingredients used to treat hypertension were studied, more specifically the blockers calcium channel dihydropyridine group: amlodipine besylate, nifedipine and nimodipine. The aim of this study was to determine the intrinsic stability of amlodipine besylate, nifedipine and nimodipine. For this purpose the following stability test techniques were used: UV/VIS spectrophotometry and chromatography Net phase High Performance. Thermogravimetry/Derivative Thermogravimetry (TG/ DTG), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), Fourier Transformed Infrared absorption (FTIR) and Scanning Electron Microscopy (MEV). For drug amlodipine besylate (AB) by forced degradation method analyzed by spectrophotometry UV/VIS spectrophotometric conditions for the analysis were methanol and water at a ratio (5:45v/v) and the second dilution with water. The reading was made at 364,4nm. The linearity was established in the range of 40.0 to 65.0 mg/mL and the correlation coefficient was (r) 0.9992. The chromatographic method showed different behavior of nifedipine and nimodipine substances on the basic means, acid, neutral and oxidative. The conditions for nifedipine were LiChrospher®100 RP-18 column (5µm) Merck® mobile phase consisting of methanol and water (45:55v/v), flow 1.0 mL/min, retention time 5,1min, UV detection at 234 nm and flow of 1.0 mL/min. Linearity was obtained within the range of 5.0-55.0 mg/mL correlation coefficient (r) = 0.9964. And for nimodipine the parameters were: LiChrospher®100 RP-18 column (5µm) Merck® mobile phase consisted of acetonitrile: water (55:45v/v), flow 1.0 mL/min, retention time 5,8min, UV detection at 235nm and flow of 1.0 mL/min. The linearity was obtained within the range of 5.0- 55.0 mg/mL correlation coefficient (r) = 0.9964. The results of TG/DTG and DSC curves presented the profile of the thermal decomposition of the substances studied by DSC. The results of XRD and DSC presented no evidence of polymorphism in these analyzes, however, according to analyzes of absorption spectroscopy in the infrared (FTIR) there were no significant differences in the raw materials and standard reference. SEM analyzes allowed to observe the crystallinity of the studied substances


Assuntos
Espectrofotometria Ultravioleta/instrumentação , Preparações Farmacêuticas/análise , Nifedipino/análise , Nimodipina/análise , Cálcio , Anlodipino/análise , Polimorfismo Genético/fisiologia , Termogravimetria/métodos , Métodos de Análise Laboratorial e de Campo/análise , Cromatografia , Acidente Vascular Cerebral , Análise Diferencial Térmica , Análise Diferencial Térmica/instrumentação , Hipertensão/prevenção & controle , Infarto
5.
Egyptian Journal of Chemistry. 2008; 51 (3): 301-324
em Inglês | IMEMR | ID: emr-99640

RESUMO

Steroidal and non-steroidal anti-inflammatory agents such as oxicam group [e.g. piroxicam [Pir] and tenoxicam [Ten] were investigated using thermal analyses [TA] measurements [TGA, DTGA, DTA and DDTA] in comparison with El mass spectral [MS] fragmentation at 70 eV. Semi-emperical molecular orbital [MO] calculations have been carried out using PM3 described by Stewart on Pir and Ten both as neutral molecules and the corresponding positively charged molecular ions. These calculations included molecular geometries such as bond length, bond order, bond strain, atomic charge distribution and hybridization, and heat of formation of these drugs. Thermal analyses reveal a high response of Pir and Ten to temperature variation with a cleavage of six bonds in aliphatic side chains around O, S, and N heteroatom, leaving aromatic radicals as final products, which become volatile at high temperature. TA mostly involved fragmentation of SO2 gas molecule at first followed by C, N, and O containing fragments as CH3CN, CHO, NHCONHCO, and NHCO. The MS fragmentations indicate the presence of the same final products as given by TA technique. Mass fragmentation pathways refer to the loss of more or less the same fragments via cleavage of seven bonds of Pir and nine bonds of Ten molecular ions, in parallel and many consecutive steps as explained by geometries values calculated by MOC. These may refer to the instability of Pir and Ten molecular ions in comparison with their neutral forms. This instability is explained by comparison of the calculated partial charges on their atoms and/or their heat of formation values. The best pathway in both TA and MS techniques is that starts with the loss of SO2 gas molecule and followed by the loss of HCO and CH3CN molecules. The partial charge values and the stereo structures of ionic and neutral form refer to a distinct phenomenon of collection of voluminous charge density on SO2 group covering in space most atoms behind. It is explained by the highest electron withdrawing abilities of the heteroatom, two O and S in this group as a result of their high electro negativities. This rationalized the starting of fragmentation process in TA and MS with the loss of SO2 gas molecules. Therefore, a MOC was applied to declare both TA and MS observations


Assuntos
Piroxicam/análogos & derivados , Inibidores de Ciclo-Oxigenase , Análise Diferencial Térmica/instrumentação , Espectrometria de Massas/instrumentação
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