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1.
Hig. aliment ; 33(288/289): 3122-3126, abr.-maio 2019. tab, graf
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1482526

ABSTRACT

A utilização de subprodutos em um novo processo resulta em maior lucro para o produtor. Entretanto, deve-se verificar a qualidade do produto final, pois a maior concentração do soro do leite pode provocar redução em parâmetros como viscosidade e sinérese. O objetivo do presente estudo é de analisar o comportamento reológico de achocolatado industrializado de duas diferentes marcas. Para leitura da viscosidade foi utilizado um viscosímetro de Brookfield, modelo DVII+Pro utilizando o splidlen nº 2 com as seguintes rotações: 50, 60, 70, 80, 100, 120, 140 rpm. A partir de uma análise estatística dos dados obtidos, utilizando o software STATISTICA 7.0 obtivemos os dados referentes à tensão de cisalhamento (Pa) e taxa de deformação (s-1). Valores inferiores de viscosidade aparente e taxa de deformação foram observadas na amostra 1, Ambas as amostras, demonstraram o comportamento de um fluido não newtoniano com características semelhantes ao plástico de Bingham.


Subject(s)
Chocolate/analysis , Rheology/methods , Whey/chemistry , Viscosity , Dairying
2.
Rev. méd. Hosp. José Carrasco Arteaga ; 10(2): 93-97, Jul 2018. Cuadros, Gráficos
Article in Spanish | LILACS | ID: biblio-999986

ABSTRACT

INTRODUCCIÓN: El nacimiento prematuro representa un problema de salud pública importante a nivel mundial y en especial en países en vías de desarrollo. En el Ecuador, en el año 2014, la tasa de mortalidad infantil fue de 8.35 defunciones infantiles por cada 1 000 nacimientos y las principales causas de mortalidad infantil fueron la dificultad respiratoria del recién nacido y los trastornos con duración corta de la gestación. MÉTODOS: El presente es un estudio observacional, descriptivo y longitudinal, realizado con una muestra censal o por conveniencia de 36 mujeres que cursaron entre 24 y 34 semanas de gestación con feto único vivo, riesgo de parto pretérmino e indicación de maduración pulmonar con corticoides. Se recogió información de flujometría fetal para determinar el efecto del uso de corticoides para maduración pulmonar. Se realizaron pruebas de normalidad Shapiro-Wilk en los resultados obtenidos antes y después de la maduración pulmonar. Para el procesamiento de los datos se utilizaron los programas Microsoft Excel® y SPSS® v.20. RESULTADOS: La edad media de este grupo fue de 25.64 años, las media de semanas de gestación fue de 31.2. La patología más frecuente fue amenaza de parto pretérmino con un 72 %, seguida de ruptura prematura pretérmino de membranas con un 13.9 %. Existió una diferencia estadísticamente significativa entre los valores de los índices Tiempo de Acelereción / Tiempo de Eyección antes y después de la maduración pulmonar (0.272 ms y 0.310 ms, respectivamente; P < 0.0001). CONCLUSIONES: La comparación de las medias de los índices Tiempo de Acelereción / Tiempo de Eyección del tronco de la arteria pulmonar pre y post maduración pulmonar con corticoides evidenció una diferencia significativa importante. Los hallazgos sugieren que la maduración pulmonar con corticoides es eficaz para mejorar el flujo de arteria pulmonar en fetos prematuros.


BACKGROUND: Premature birth represents an important public health problem worldwide and especially in developing countries. In Ecuador (2014), the infant mortality rate reached 8.35 deaths per 1 000 births and their main causes were newborns respiratory distress and gestation period short-term disorders. METHODS: This is an observational longitudinal descriptive research; it was performed in a convenience sample that included 26 singlet on pregnant women between 24 and 34 weeks of gestation. They also were on risk of preterm delivery and had indication of lung maturation with corticosteroids. Information of the fetal pulmonary arteries flow was collected to determine the effect of corticosteroids in pulmonary maturation. RESULTS: Mean age was 25.64 years and had an average gestation of 31.2 weeks. Most common diseases were preterm labor threat (72 %) and premature rupture of membranes (13.9 %). There was a statistically significant difference between the values of Acceleration Time / Ejection Time indexes before and after lung maturation (0.272 ms vs. 0.310 ms respectively; P < 0.0001). CONCLUSIONS: Comparison of Acceleration Time / Ejection Time indexes from the trunk of the pulmonary arteries before and after lung maturation evidenced an important significant difference. The findings suggest that pulmonary maturation with corticosteroids is effective to improve the pulmonary arteries flow of preterm fetus.


Subject(s)
Humans , Female , Pregnancy , Infant, Premature , Adrenal Cortex Hormones/therapeutic use , Fetal Organ Maturity/drug effects , Rheology/methods
3.
Int. braz. j. urol ; 41(3): 521-526, May-June 2015. tab, ilus
Article in English | LILACS | ID: lil-755868

ABSTRACT

ABSTRACT

To evaluate different flowmetry/EMG patterns in patients with proven detrusor overactivity (DO) and compare them with that of a group of patients with lower urinary tract symptoms (LUTS) but without DO.

Materials and Methods

We retrospectively evaluated the records of 100 patients with frequent urinary tract infection or any kind of storage or voiding symptoms that had undergone urodynamic testing: 50 cases with proven DO on cystometry who had a good quality flowmetry/EMG and 50 patients without DO. EMG lag time (the time distance between pelvic floor EMG inactivation and the start of urine flow) and different flow curve pattern were recorded and compared.

Results

The age and gender distribution were not statistically significant between the two groups. A negative lag time (≤ 0 sec) and an obstructive pattern were the only parameters that were more commonly seen in the DO group. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of a lag times <2 sec for diagnosing DO were 70%, 96%, 96% and 72%, respectively. For a negative lag time, they were 52%, 100%, 100% and 63%, respectively.

Conclusions

A lag time < 2 sec is a useful flowmetric finding that effectively rules out patients with LUTS that do not have DO (specificity and PPV=96%). With the cutoff of zero or less, specificity and PPV will be 100%. It has lower sensitivity and NPV, however, and is not measurable in a considerable population of patients with DO that have concomitant DV.

.


Subject(s)
Adolescent , Adult , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Young Adult , Electromyography/methods , Rheology/methods , Urinary Bladder, Overactive/physiopathology , Age Distribution , Lower Urinary Tract Symptoms/physiopathology , Pelvic Floor/physiopathology , Reference Values , Retrospective Studies , Sensitivity and Specificity , Time Factors , Urodynamics/physiology
4.
São Paulo; s.n; s.n; 2015. 238 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-834146

ABSTRACT

O aumento da demanda por alimentos saudáveis está estimulando inovações e o desenvolvimento de novos produtos na indústria de alimentos. O amaranto (Amaranthus cruenthus L.) e a quinoa (Chenopodium quinoa W.) são pseudocereais que apresentam proteínas de elevado valor biológico e ácidos graxos insaturados além de outros compostos que atuam como antioxidantes. A maca (Lepidium meyenii W.), uma raiz anual ou bienal, é usada como ingrediente alimentar devido ao seu valor nutricional e conteúdo de fitoquímicos. Neste trabalho, objetivou-se avaliar o efeito da adição das farinhas destas cullturas em diferentes níveis sobre as propriedades físico-químicas, reológicas e sensoriais de panetone. Farinhas mistas de trigo e amaranto, quinoa ou maca nas porcentagens de 10 %, 20 %, 30 % e 40 % de adição, foram avaliadas durante as diferentes etapas de produção: misturas de farinhas, massa fermentada, massa assada e produto acabado. A adição favoreceu o escurecimento gradual das farinhas e variação no tamanho médio das partículas. Nas massas, foi observada a diminuição gradativa dos valores de estabilidade ao amassamento e tempo de desenvolvimento com diminuição da extensibilidade e aumento da resistência das massas. Nas massas fermentadas, a adição de 10 e 20 % de farinha de amaranto ou quinoa e 30 % de farinha de amaranto, não incrementou significativamente (p > 0,05) a firmeza da massa. No entanto, as formulações contendo farinha de maca mostraram aumento significativo (p < 0,05) no ponto de quebra, firmeza, consistência, coesividade e viscosidade da massa. O aumento da resistência com diminuição gradativa da extensibilidade das massas também foi observado. Nas massas assadas, houve diminuição da área total de células com aumento no número de células de gás de menor tamanho em amostras com adição de farinha de maca e amaranto. As formulações com 10 % de farinha de maca, 10 e 20 % de farinha de amaranto ou quinoa e 30 % de farinha de amaranto, apresentaram os melhores resultados, com valores de volume, altura, cor e firmeza próximos à formulação controle. A análise sensorial mostrou que o produto elaborado com adição de 30 % de farinha de amaranto apresentou a melhor aceitabilidade e intenção de compra. Dentro das condições experimentais, o panetone contendo 30 % de farinha de amaranto foi o mais promissor pela boa aceitabilidade do consumidor, podendo contribuir para incrementar a qualidade do produto. O panetone com 10 % de adição de farinha de maca também apresentou valores interessantes com pouca diferença se comparado com aquele enriquecido com farinha de amaranto. Na amostra contendo farinha de quinoa, a substituição com menos de 20 % de adição melhoraria a aceitabilidade do panetone enriquecido


The increased demand for healthy foods is stimulating innovation and new product development in the food industry. Amaranth (Amaranthus cruenthus L.) and quinoa (Chenopodium quinoa W.) are pseudocereals which have proteins with high biological value and unsaturated fatty acids, as well as other compounds which act as antioxidants. Maca (Lepidium meyenii W.), an annual or biennial root, is used as a food ingredient for human consumption due to its nutritional value and phytochemical content. The objective of this study was to evaluate the effect of amaranth, quinoa and maca flour addition at different levels on the physical-chemical, rheological and sensory properties of panettone. Composite flours of wheat and amaranth, quinoa or maca flours in percentages of 10 %, 20 %, 30 % and 40 % addition were evaluated during the different stages of production: flour blends, fermented dough, baked dough and finished product. The addition promoted a gradual flour darkening and tendency to yellow and red colors. In the dough, the gradual decrease in stability values to kneading and development time with decreased extensibility and increased dough resistance, were observed. In fermented doughs, the addition of 10 % - 20 % amaranth or quinoa flour and 30 % amaranth flour, did not increased significantly (p > 0.05) the dough firmness. However, formulations containing maca flour showed a significant increase (p < 0.05) of break point, firmness, consistency, cohesiveness and viscosity of the dough. Furthermore, it was also observed an increase in dough resistance with a gradual decrease in extensibility. In baked samples, there was a decrease of the total cell area with increased number of smaller gas cells in samples with maca and amaranth flour addition. Better results were observed in formulations with 10% maca flour, 10 - 20 % amaranth or quinoa flour and 30 % amaranth flour with values of volume, height, color and firmness close to the control. Sensorial analysis showed that sample containing 30 % addition of amaranth flour showed the better acceptability and purchase intention by consumers. Within these experimental conditions, panettone containing 30 % amaranth flour was the most promising for the good acceptability of the consumer and may contribute to improve the quality of the product. Sample with 10 % maca flour addition also showed interesting values with few differences when compared to that enriched with amaranth flour. In sample containing quinoa flour, wheat flour substitution with less than 20 % would improve the acceptability of the enriched panettone


Subject(s)
Flour Industry , Amaranthus/classification , Chenopodium quinoa/classification , Lepidium/classification , Flour/analysis , Rheology/methods , Whole Foods
5.
Rev. cuba. farm ; 48(1): 5-12, ene.-mar. 2014. Ilus, tab
Article in Spanish | LILACS, CUMED | ID: lil-721279

ABSTRACT

OBJETIVO: desarrollar una solución oftálmica de dorzolamida 2 % más timolol 0,5 % que cumpla con todos los requerimientos de calidad para proporcionar el efecto terapéutico deseado sin efectos adversos al paciente. MÉTODOS: se prepararon tres ensayos preliminares en los que se utilizaron clorhidrato de dorzolamida y maleato de timolol, una solución tampón que consistió en ácido cítrico monohidratado/citrato trisódico dihidratado, cuyo pH estuviese en el rango de 5 y 6, cloruro de benzalconio, y HPMC F4M (hidroxipropilmetilcelulosa) al 10 %. Se usaron estos componentes en sustitución de los recomendados en la literatura. Se estudió la estabilidad química y física de la formulación durante 3 meses en cuanto a las características organolépticas, concentración del ingrediente activo, el pH, así como las propiedades fluidimétricas, irritabilidad oftálmica y efectividad del preservo. Con la formulación de estudio se desarrolló y se validó la técnica analítica en el Centro de Investigación y Desarrollo de Medicamentos. Se determinó la linealidad, precisión, especificidad y exactitud de método. Se elaboraron tres lotes pilotos de 5 L cada uno. Se utilizó como material de envase frascos plásticos de polietileno de baja densidad con Master Batch de 5 mL de capacidad. RESULTADOS: los ingredientes activos, clorhidrato de dorzolamida y maleato de timolol, y los excipientes de calidad farmacéutica y el material de envase utilizado cumplieron con las especificaciones de calidad informados en la USP 33. Los análisis fisicoquímicos realizados a los tres lotes del escalado piloto e industrial cumplieron con las especificaciones de calidad de la técnica analítica desarrollada por el Departamento de Estabilidad del Centro de Investigación y Desarrollo de Medicamentos y con los análisis microbiológicos informados en la USP 33. CONCLUSIONES: los resultados obtenidos permiten la introducción industrial y sustituir la importación del referido medicamento.


OBJECTIVE: to develop a 2 % dorzolamide plus 0.5 % timolol eye drop solution with all the quality requirements to provide adequate therapeutic effect without adverse reactions for the patients. METHODS: three preliminary trials were prepared with dorzolamide chlorhydrate and timolol maleate, a buffer solution based on monohydrated citric acid/dehydrated trisodic citrate with pH range 5-6, benzalkonium chloride and 10 % HPMC F4M (hydroxypropilmetylcellulose). These components replaced those recommended in the literature review. The chemical and physical stability of this formulation was studied for three months in terms of organoleptic characteristics, active ingredient concentration, pH, fluidmetric properties, eye irritability and effectiveness of preserver. The study formulation allowed developing and validating the analytical technique of the Center for the Drug Research and Development. Linearity, precision, specificity and accuracy of the method were determined. Three 5 L pilot batches were prepared. Master Batch 5 mL low-density polyethylene plastic bottles were used for packing. RESULTS: active ingredients, dorzolamide chlorhydrate and timolol maleate, the pharmaceutical quality excipients and the packing material met the quality specifications according to USP 33. The physical and chemical analysis of the three batches at pilot and industrial scales met the quality specifications of the analytical technique devised by the Department of Stability of the Center for Drug Research and Development and the microbiological analysis reported in USP 33. CONCLUSIONS: the achieved results allowed introducing the formulation at industrial scale and replacing the imported drug.


Subject(s)
Humans , Ophthalmic Solutions/therapeutic use , Rheology/methods , Timolol/therapeutic use , Drug Stability
6.
Braz. j. pharm. sci ; 50(4): 931-941, Oct-Dec/2014. tab, graf
Article in English | LILACS | ID: lil-741355

ABSTRACT

Rational design of vaginal drug delivery formulations requires special attention to vehicle properties that optimize vaginal coating and retention. The aim of the present work was to perform a screening of mucoadhesive vaginal gels formulated with carbomer or carrageenan in binary combination with a second polymer (carbomer, guar or xanthan gum). The gels were characterised using in vitro adhesion, spreadability and leakage potential studies, as well as rheological measurements (stress and frequency sweep tests) and the effect of dilution with simulated vaginal fluid (SVF) on spreadability. Results were analysed using analysis of variance and multiple factor analysis. The combination of polymers enhanced adhesion of both primary gelling agents, carbomer and carrageenan. From the rheological point of view all formulations presented a similar behaviour, prevalently elastic and characterised by loss tangent values well below 1. No correlation between rheological and adhesion behaviour was found. Carbomer and carrageenan gels containing the highest percentage of xanthan gum displayed good in vitro mucoadhesion and spreadability, minimal leakage potential and high resistance to dilution. The positive results obtained with carrageenan-xanthan gum-based gels can encourage the use of natural biocompatible adjuvants in the composition of vaginal products, a formulation field that is currently under the synthetic domain.


O planejamento racional de formulações para a liberação vaginal de fármacos requer atenção especial às propriedades do veículo, que otimizem o revestimento e a retenção vaginal. O objetivo do presente trabalho foi realizar uma triagem de géis vaginais mucoadesivos formulados com carbomero ou carragenina em combinação binária com um segundo polímero (carbomero, goma guár ou xantana). Os géis foram caracterizados usando estudos in vitro de aderência, espalhabilidade e potencial de vazamento, bem como medições reológicas (testes de varredura de tensão e frequência) e o efeito de diluição com fluido vaginal simulado (SVF) na espalhabilidade. Os resultados foram analisados utilizando a análise de variância e de fator múltiplo. A combinação de polímeros reforçou a adesão de ambos os agentes gelificantes primários, carbomero e carragenina. Do ponto de vista reológico todas as formulações apresentaram comportamento semelhante, predominantemente elástico e caracterizado por valores de tangente de perda bem abaixo de 1. Não se encontrou correlação entre as medições reológicas e o comportamento de adesão. Os géis de carbomero e carragenina contendo o maior porcentual de goma xantana apresentaram melhor mucoadesão e espalhabilidade, menor potencial de vazamento e maior resistência à diluição in vitro. Os resultados positivos obtidos com géis de carragenina-goma xantana podem incentivar o uso de adjuvantes biocompatíveis naturais na composição dos produtos vaginais, um campo de formulação atualmente sob o domínio de produtos sintéticos.


Subject(s)
Vaginal Creams, Foams, and Jellies/analysis , Chemistry, Pharmaceutical/methods , Rheology/methods , Straining of Liquids/classification , Drug Liberation
7.
Article in Portuguese | LILACS | ID: lil-705083

ABSTRACT

A monoleína é um lipídeo polar capaz de absorver água e formar sistemas líquido-cristalinos, os quais são utilizados como sistemas de liberação para administração de vários fármacos. Neste estudo foi avaliado o potencial de sistemas de fase lamelar constituídos por monoleína e água para veicular polihexametilenobiguanida (PHMB). A formação dos sistemas líquido-cristalinos foi caracterizada por microscopia de luz polarizada. Estudos de intumescimento foram realizados gravimetricamente em várias condições avaliando-se os efeitos de parâmetros como pH, força iônica e temperatura do meio de imersão. O processo de intumescimento foi caracterizado através da obtenção dos perfis de intumescimento e análise de sua cinética, além da determinação da capacidade máxima de intumescimento dos sistemas. Os sistemas de fase lamelar foram obtidos em presença de PHMB, os quais absorveram água rapidamente de acordo com cinética de segunda ordem e sofreram transição de fase, formando a fase cúbica. O intumescimento dos sistemas não foi influenciado pela presença do fármaco nos vários meios de imersão estudados, exceto pela imersão em meio ácido, no qual a presença do PHMB aumentou a captação de água. O intumescimento dos sistemas contendo PHMB não foi afetado pela força iônica do meio de imersão, porém foi diminuído com o aumento da temperatura. Desta maneira, sistemas líquido-cristalinos de monoleína e água foram obtidos e o processo de intumescimento foi caracterizado. Os sistemas apresentaram potencial para serem propostos como sistemas de liberação para administração de PHMB e estudos de liberação de fármacos serão realizados futuramente.


Monoolein is a polar lipid that absorbs water and forms liquid crystalline systems that are used as drug delivery systems for different medications. The aim of the present study was to investigate lamellar phases formed by monoolein and water as potential vehicles for the administration of polyhexamethylene biguanide (PHMB). Lamellar phase systems formed by monoolein and water containing PHMB were characterized by polarizing microscopy. Swelling studies were performed gravimetrically under different conditions for the evaluation of the effects of pH, ionic strength and temperature. Analyses of swelling profiles, swelling kinetics and maximum swelling capacity were performed. The lamellar phase systems of monoolein and water obtained in the presence of PHMB absorbed water very quickly following second-order swelling kinetics and formed a cubic phase. The swelling of the systems was not influenced by the presence of the drug in the immersion media studied, except under acidic conditions, in which the drug exhibited increased water uptake. The swelling of systems containing PHMB was not affected by the ionic strength of the immersion media, but was reduced with an increase in temperature. Liquid crystalline systems of monoolein and water were obtained and swelling behavior was investigated. The systems exhibited the potential for use as a drug delivery system for PHMB administration. However, further drug-release studies should be performed.


Subject(s)
Liquid Crystals , Lipids/biosynthesis , Pharmaceutical Preparations/analysis , Chemistry, Pharmaceutical/methods , Rheology/methods
8.
Rev. bras. cir. cardiovasc ; 27(2): 283-289, abr.-jun. 2012. ilus, tab
Article in Portuguese | LILACS | ID: lil-649605

ABSTRACT

INTRODUÇÃO: A cirurgia de revascularização do miocárdio (RM) sem circulação extracorpórea (CEC) é uma técnica amplamente utilizada. A fluxometria coronariana é a técnica mais usada para avaliação dos enxertos, porém, poucos estudos comparam os dados fluxométricos na RM com e sem CEC. O objetivo deste estudo foi comparar as variáveis fluxométricas dos enxertos de artéria torácica interna esquerda para a artéria descendente anterior em pacientes submetidos à RM com e sem CEC. MÉTODOS: Entre março e setembro de 2010, foram analisados retrospectivamente 35 pacientes consecutivos, não randomizados, submetidos à RM. Foram alocados 10 pacientes no grupo A (com CEC) e 25 no grupo B (sem CEC). O fluxo médio do enxerto (FME), o índice pulsátil (PI) e a porcentagem de enchimento diastólico (ED) foram obtidos por meio da fluxometria por tempo de trânsito. Foi utilizado o teste exato de Fisher e Mann-Whitney, sendo considerado estatisticamente significante P<0,05. RESULTADOS: Não houve óbito, infarto agudo do miocárdio ou necessidade de angioplastia em 30 dias de pós-operatório. O número médio de anastomoses distais foi 2,3 ± 0,8 por paciente no grupo sem CEC, e de 2,2 ± 0,6 no grupo com CEC (P=0,10). A mediana do fluxo médio do enxerto foi 23 ml/min, no grupo A, e 25 ml/min, no grupo B (P=0,34). A percentagem de enchimento diastólico foi 56%, no grupo A, e 59,5%, no grupo B (P=0,86). O índice pulsátil foi 2,3, no grupo A, e 2,2, no grupo B (P=0,82). CONCLUSÃO: Não houve diferença nos parâmetros fluxométricos (FME, ED e PI) encontrados nos pacientes submetidos à revascularização do miocárdio com e sem CEC.


BACKGROUND: Off-pump coronary bypass grafting (OPCAB) has become a widely used technique. Coronary flowmetry is the most common method employed to assess graft patency, nevertheless, few studies compare flow patterns between ONCAB and OPCAB surgery. The objective of this study was to compare flowmetry data in left internal mammary artery grafts bypasses to the left anterior descendent artery. METHODS: From March to September of 2010, thirtyfive consecutive, non-randomized patients underwent CABG and were retrospectively evaluated. Ten patients were located on group A (On Pump), and twenty-five on group B (Off Pump). The mean graft flow (MGF), pulsatile index (PI) and diastolic filling (DF) were obtained using Transit Time Flowmetry (TTFM). The Fisher exact test, and Mann Whitney test were used, and a P value of < 0.05 was considered to indicate statistical significance. RESULTS: There were no deaths, AMI, re-interventions or PTCA in a 30-day period. The number of bypasses performed per patient was 2.3 ± 0.8 in the OPCAB group, and 2.2 ± 0.6 in the ONCAB group, with no significant difference (P=0.10). The median of mean flow was 23 ml/min on group A, and 25 ml/min on group B (P=0.34). Diastolic filling percentage was 56% on group A, and 56.9% on group B (P=0.86). Pulsatile Index was 2.3 on group A, and 2.2 on group B (P=0.82). CONCLUSIONS: There was no difference between TTFM values (MF, PI and DF) in patients operated with or without cardiopulmonary bypass.


Subject(s)
Aged , Female , Humans , Male , Middle Aged , Coronary Artery Bypass/methods , Extracorporeal Circulation/methods , Mammary Arteries/physiology , Rheology/methods , Coronary Artery Bypass, Off-Pump/methods , Pulsatile Flow , Retrospective Studies , Statistics, Nonparametric , Time Factors
9.
Article in Portuguese | LILACS | ID: lil-535426

ABSTRACT

Ascorbic acid (AA), or vitamin C, is widely used in the pharmaceutical, cosmetic and food industries as an antioxidant and cosmetics containing AA have been gaining popularity in the last few years for the treatment of photoageing. To solve the problem of its low stability, some esters have been synthesised, such as magnesium ascorbyl phosphate (MAP), also available encapsulated in collagen-based microspheres (EMAP). The aim of this research was to study the physical and chemical stability of O/W emulsions containing AA, MAP or EMAP, by rheological and HPLC analysis, respectively. These emulsions were stored at 25, 37 and 45ºC for 28days and samples tested weekly during storage. It was concluded that all the formulations showed pseudoplastic behaviour. The presence of MAP provoked an initial rise in thixotropy. The formulation containing AA did not show any marked change in rheological behaviour. In the chemical analysis, the formulation with EMAP was more stable than those with MAP and AA. Hence, replacement of AA with EMAP in this cosmetic formulation may be a viable way to enhance the stability of the active principle.


Cosméticos contendo ácido ascórbico (AA) têm sido muito empregados nos últimos anos na prevenção e tratamento do fotoenvelhecimento cutâneo. Para solucionar o problema de sua baixa estabilidade, alguns derivados têm sido utilizados como substitutos dessa vitamina e dentre eles o Magnesium Ascorbyl Phosphate (MAP), disponível também em microesferas à base de colágeno (EMAP). O objetivo desta pesquisa foi estudar a reologia e a estabilidade química de emulsões contendo AA, MAP ou EMAP. Assim, formulações contendo AA, MAP ou EMAP foram armazenadas a 25, 37 e 45ºC durante 28 dias e avaliadas. Concluiu-se que todas as formulações apresentaram comportamento pseudoplástico. A presença de MAP provocou um aumento inicial da tixotropia e a formulação contendo AA não apresentou grande alteração no comportamento reológico. Nos estudos químicos a formulação contendo EMAP foi mais estável que o MAP e AA, com o maior prazo de validade. Desta forma, a substituição de AA pela EMAP em cosméticos pode ser uma alternativa viável do ponto de vista da estabilidade da formulação.


Subject(s)
Ascorbic Acid , Cosmetic Stability , Drug Stability , Rheology/methods
10.
Rev. Assoc. Med. Bras. (1992) ; 54(2): 139-141, mar.-abr. 2008. tab
Article in Portuguese | LILACS | ID: lil-482904

ABSTRACT

OBJETIVO: Avaliar as taxas de fluxo no estudo urodinâmico (EUD) em pacientes com disfunção do trato urinário inferior e registrar os efeitos do diagnóstico final do EUD e da idade das pacientes sobre estas variáveis. MÉTODOS: Estudo retrospectivo que incluiu 205 mulheres. As pacientes foram divididas em três grupos: menos de 45 anos; entre 45 e 60 anos e mais que 60 anos. Estudamos os comportamentos dos fluxos máximo, médio e da pressão de abertura do detrusor (Padet) com o evoluir da idade. De forma semelhante, realizamos comparações das variáveis fluxos máximo e médio, Padet e vesical no fluxo máximo, consoante o diagnóstico final do EUD. RESULTADOS: Há forte declínio dos fluxos máximo, médio e da Padet com o evoluir da idade, sendo que a queda dos fluxos máximo e médio é significante quando comparamos as mulheres com mais de 65 anos (21,8 ml/s e 9,2 ml/s, respectivamente) com aquelas entre 45 e 60 anos (29 ml/s e 12,6 ml/s, respectivamente) e as demais (27,9 ml/s e 11,7 ml/s, respectivamente). Observamos redução significativa da Padet no grupo com mais de 60 anos (13,4 cmH2O) quando comparadas àquele com menos de 45 anos (21,2 cmH2O). A Padet teve redução significativa nas pacientes com incontinência urinária de esforço (IUE) associada a defeito esfincteriano (13,8 cmH2O) diagnosticados no EUD quando comparadas aquelas assintomáticas (20,7 cmH2O). CONCLUSÃO: Há diminuição das taxas de fluxo com o aumento da idade. Mulheres com IUE têm micção com menor Padet.


OBJECTIVE: The purpose was to evaluate urine flow rates in an urodynamic study (US) of patients with symptoms of lower urinary tract dysfunction and to record effects of final urodynamic diagnosis and age on these variables. METHODS: Retrospective analysis of 205 women who had undergone urogynecological investigation. Patients were divided into three age groups: A (< 45 years); B (45 - 60 years) and C (> 60 years). Comportment of urine flow rates and opening detrusor pressure with increasing age were studied and resulting charts recorded. Comparison of maximum and average urine flow rates, opening detrusor pressure and detrusor pressure at the maximal flow according to final urodynamic diagnostic were also made. RESULTS: There was a decline of urine flow rates with increase of age, which was more significant between groups A X C and B X C. There was also a decline in opening detrusor pressure with aging, which was significant between groups A X C. When analyzing opening detrusor pressure according to final urodynamic diagnosis, a significant decline of this variable was observed in patients with urinary stress incontinence and intrinsic sphincter deficiency in relation to those who were asymptomatic. CONCLUSION: Urine flow rates decreased with age. Women with urinary stress incontinence and intrinsic sphincter deficiency void at a lower detrusor pressure.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Middle Aged , Young Adult , Urodynamics , Urinary Bladder/physiopathology , Urinary Incontinence, Stress/diagnosis , Age Factors , Pressure , Retrospective Studies , Rheology/methods , Urinary Incontinence, Stress/physiopathology , Urination/physiology , Young Adult
11.
Braz. j. vet. res. anim. sci ; 45(1): 57-66, 2008. ilus, tab
Article in Portuguese | LILACS | ID: lil-488556

ABSTRACT

Foram utilizados 20 gatos sem raça definida, com massa corpórea entre 2 e 4 quilogramas, hígidos, anestesiados com tiletamina e zolazepam (6,0 mg/kg). A artéria femoral foi canulada de forma asséptica e um manômetro acoplado a uma coluna de ar foi conectada ao cateter, a PAM foi aferida antes e a cada 15 minutos até o término do exame ultra-sonográfico. A fluxometria da artéria oftálmica externa foi obtida através do equipamento de ultra-sonografia dotado de eco-doppler, com transdutor setorial de 6,0 MHz, aplicado diretamente sobre a córnea. Cada olho teve o fluxo de sua artériaaferido pelo programa do próprio aparelho, sendo tomadas três amostras. O índice de resistência vascular foi calculado com base nos valores do fluxo sistólico e diastólico médio de cada vaso. Obteve-se um valor médio para a PAM de 144,9 ± 26,68 mmHg e uma velocidade de fluxo de 41,3 ± 14,28 cm/s para a artéria oftálmica externa no olho direito em sístole, 23,95 ± 11,46 cm/s em diástole e 42,75 ± 12,64 cm/s no olho esquerdo em sístole, 25,45 ± 9,61 cm/s em diástole, não existindo diferença significativa entre os olhos. O índice de resistência vascular calculado foi de 0,4175 para a artéria oftálmica externa no olho direito e 0,4015 para a do olho esquerdo, sem diferença significativa entre os olhos. Os resultados apontam para um mecanismo intrínseco de controle do fluxo, controlado por fatores locais na artéria oftálmica externa. Os valores do índice de resistência denotam uma artéria de baixo fluxo. Como conclusão, têm-se os valores de referência acima citados para a PAM e para o fluxo sangüíneo na artéria oftálmica externa em gatos sem raça definida anestesiados com tiletamina e zolazepam, e a informação de que não existe correlação entre esses valores.


There were used 20 mixed breed cats, both male and female, with body mass between 2 and 4 kilograms, that received anesthesia with tiletamine and zolazepam (6,0 mg/kg). The femoral artery was assepticale cannulated and a manometer connected to an air column was connected to the catheter. The MAP was surveyed before and every 15 minutes until the end of the ultrasound examination. The flow of the external ophthalmic artery was measured through the ultrasond equipment, with an echo-doppler and a sectorial transducer of 6.0 MHz, directly applied to the cornea. Each eye had the artery flow surveyed by the equipment's own device, 3 samples being taken. The vascular resistance index was calculated based on the mean values of systolic and diastolic flow of each vasses. An average value for the MAP of 144.9 ± 26.68 mmHg and a flow of 14.28 ± 41.3 cm/sec for the external ophthalmic artery in the right eye in systole, 23.95 ± 11.46 cm/sec in diastole and 42.75 ± 12.64 cm/sec in the left eye in systole, 25.45 ± 9.61 cm/sec in diastole, were verified, there being no significant difference between the eyes. The calculated index of vascular resistance was of 0.4175 ± 0.0774 for the external ophthalmic artery in the right eye and 0,4015 ± 0.0719 for the left eye, without any significant difference between the eyes. The results point to an intrinsic mechanism of flow control, controlled by local factors in the external ophthalmic artery. The values of the resistance index denote a low flow artery. Concluding, this study revealed the reference values, above cited, for the MAP and the blood flow in the external ophthalmic artery in mixed breed cats, anesthetized with tiletamine and zolazepam, and the information that there is no correlation between these values.


Subject(s)
Animals , Ophthalmic Artery/physiology , Cats , Regional Blood Flow/physiology , Eye Diseases/veterinary , Rheology/methods
12.
Rev. bras. ecocardiogr ; 20(3): 12-21, jul.-set. 2007. tab, ilus, graf
Article in Portuguese | LILACS | ID: lil-485738

ABSTRACT

Fundamentos: A adesão das microesferas aos leucócitos no tecido inflamado tem sido discutida, porém, pouco se sabe sobre seu comportamento nos capilares. A avaliação dos efeitos circulatórios desse agente pode trazer informações sobre sua ação no miocárdio. Objetivo: Avaliar o comportamento microvascular e hemodinâmico das microesferas nos seguintes grupos: controle, isquemia-reperfusão, diabetes tipo 2, diabetes com isquemia e sepsis. Métodos: Experimentalmente estudou-se a microcirculação da bolsa da bochecha de 65 hamsters machos, sendo separados por grupos conforme a indução da doença de base G-1 igual isquemia/reperfusão. GD igual diabetes, GDI igual diabetes com isquemia GS igual sepsis em relação ao GC (grupo controle). Dentro de cada grupo avaliou-se a pressão arterial...


Subject(s)
Animals , Mice , Microspheres , Microcirculation/physiology , Rheology/methods , Diabetes Mellitus/classification , Diabetes Mellitus/diagnosis , Sepsis/complications
14.
J Postgrad Med ; 2002 Jul-Sep; 48(3): 182-5; discussion 185
Article in English | IMSEAR | ID: sea-115800

ABSTRACT

BACKGROUND: Obstetric decision- making for the growth restricted foetus has to take into consideration the benefits and risks of waiting for pulmonary maturity and continued exposure to hostile intra-uterine environment. Necrotising Enterocolitis (NEC) results from continued exposure to hostile environment and is an important cause of poor neonatal outcome. AIMS: To evaluate the predictive value of abnormal Doppler flow velocimetry of the foetal umbilical artery for NEC and neonatal mortality. SETTINGS AND DESIGN: A retrospective study carried out at a tertiary care centre for obstetric and neonatal care. MATERIALS AND METHOD: Seventy-seven neonates with birth weight less than 2000 gm, born over a period of 18 months were studied. These pregnancies were identified as having growth abnormalities of the foetus. Besides other tests of foetal well-being, they were also subjected to Doppler flow velocimetry of the foeto-placental vasculature. Obstetric outcome was evaluated with reference to period of gestation and route of delivery. The neonatal outcome was reviewed with reference to birth weight, Apgar scores and evidence of NEC. STATISTICAL ANALYSIS USED: Chi square test. RESULTS: In the group of patients with Absent or Reverse End Diastolic Frequencies (A/R EDF) in the umbilical arteries, positive predictive value for NEC was 52.6%, (RR 30.2; OR 264). The mortality from NEC was 50%. When umbilical artery velocimetry did not show A/REDF, there were no cases of NEC or mortality. Abnormal umbilical or uterine artery flow increased the rate of caesarean section to 62.5% as compared to 17.6% in cases where umbilical artery flow was normal. CONCLUSION: In antenatally identified pregnancies at risk for foetal growth restriction, abnormal Doppler velocimetry in the form of A/REDF in the umbilical arteries is a useful guide to predict NEC and mortality in the early neonatal period.


Subject(s)
Adult , Blood Flow Velocity/physiology , Chi-Square Distribution , Comorbidity , Enterocolitis, Necrotizing/epidemiology , Female , Fetal Growth Retardation/epidemiology , Follow-Up Studies , Humans , Infant Mortality/trends , Infant, Newborn , Predictive Value of Tests , Pregnancy , Prevalence , Probability , Retrospective Studies , Rheology/methods , Risk Assessment , Ultrasonography, Doppler/methods , Ultrasonography, Prenatal , Umbilical Arteries
15.
Braz. j. med. biol. res ; 30(7): 897-908, July 1997. ilus, tab, graf
Article in English | LILACS | ID: lil-197243

ABSTRACT

The objective of the present study was to validate the transit-time technique for long-term measurements of iliac and renal blood flow in rats. Flow measured with ultrasonic probes was confirmed ex vivo using excised arteries perfused at varying flow rates. An implanted 1-mm probe reproduced with accuracy different patterns of flow relative to pressure in freely moving rats and accurately quantitated the resting iliac flow value (on average 10.43 + 0.99 ml/min or 2.78 + 0.3 ml min(-1) 100 g body weight(-1)). The measurements were stable over an experimental period of one week but were affected by probe size (resting flows were underestimated by 57 per cent with a 2-mm probe when compared with a 1-mm probe) and by anesthesia (in the same rats, iliac flow was reduced by 50-60 per cent when compared to the conscious state). Instantaneous changes of iliac and renal flow during excercise and recovery were accurately measured by the transit-time technique. Iliac flow increased instantaneously at the beginning of mild exercise (from 12.03 + 1.06 to 22.55 + 3.89 ml/min at 15 s) and showed a smaller increase when exercise intensity increased further, reaching a plateau of 38.43 + 1.92 ml/min at the 4th min of moderate exercise intensity. In contrast, exercise-induced reduction of renal flow was smaller and slower, with 18 per cent and 25 per cent decreases at mild and moderate exercise intensities. Our data indicate that transit-time flowmetry is a reliable method for long-term and continuous measurementes of regional blood flow at rest and can be used to quantitate the dynamic flow changes that characterize exercise and recovery.


Subject(s)
Rats , Animals , Male , Blood Flow Velocity/physiology , Exercise/physiology , In Vitro Techniques , Rheology/methods , Laser-Doppler Flowmetry , Rats, Inbred WKY
16.
Medical Journal of Cairo University [The]. 1996; 64 (1): 263-7
in English | IMEMR | ID: emr-42190
17.
Alexandria Journal of Pharmaceutical Sciences. 1991; 6 (1): 27-31
in English | IMEMR | ID: emr-18938

ABSTRACT

The rheology of plum gum dispersion was studied utilizing the reoviscometer. The rheogram of 5% w/w gum dispersion is indicative of a pseudoplastic system, which becomes clearly plastic upon increasing gum concentration. It was also evident that sum dispersions exhibit thixotropic behavior. At relatively low concentrations [0.25-2% w/w], it was not possible to establish the actual flow pattern. Therefore, the characterization was based on measurements of relative viscosities. Various factors which influence the relative viscosity of gum dispersion, as gum concentration, preservatives type, hydrogen ion concentration and effect of heat were studied in the light of the factor of time. The relative viscosity of 2% w/w gum dispersion was reduced by about 90% by increasing the temperature from 25C to 100C. On aging, the dispersions lost part of their viscosities. Phenylmercuric nitrate was found to be the best among the other preservatives tested. Plum dispersions appeared to be most stable at pH 6 and lowering in the relative viscosities was noticed on aging


Subject(s)
Pharmacokinetics , Rheology/methods , Preservatives, Pharmaceutical/statistics & numerical data
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