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1.
J Environ Manage ; 166: 429-39, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26555099

RESUMEN

Searches related to global warming have provided important insights into the response of terrestrial ecosystems, but few have examined the impacts on agricultural crops, particularly those associated with the monitoring of agrotoxin residues. In this context, the agriclimatological zoning is an important tool in the planning and consolidation of crops and should be considered in any initiative that involves such planning. This tool is particularly important in the analysis of agrotoxin residues and may be applied by the Program Analysis of Agrotoxin Residues in Food (PARA) created by the National Health Vigilance Agency of Brazil (ANVISA), which enables greater food security and contributes to the improvement of human health. The aim of this study was to elaborate the current and future agriclimatological zoning for the tomato crop, relating it with the monitoring of samples collected by PARA in Espírito Santo State, Brazil. The results indicate that a temperature increase of 5 °C creates a decrease in apt areas from 37.3% to 4.3%, for a total reduction of 33 percentage points (-88.5%). It is noted that of the 41 producing municipalities, only 26 have apt areas greater than 50%, highlighting the municipalities with apt areas greater than 90%, represented by Mantenópolis (100%), Guaçuí (98.5%), São José do Calçado (97.8%), Irupi (94.4%), Santa Teresa (92.3%), and Marechal Floriano (91.4%). The veracity of agriclimatological zoning is proved by a Kendall rank correlation coefficient of 0.876, indicating that the distribution of the variables of apt areas and productivity are similar at the significance level of 0.05 with a confidence interval 95%. After validation of the agriclimatological zoning for the tomato crop, it is recommended that the PARA should monitor 36 municipalities rather than the current 18, representing an increase of 100%. The methodology can be adjusted to agricultural crops of other countries.


Asunto(s)
Productos Agrícolas , Contaminación de Alimentos/análisis , Sistemas de Información Geográfica , Solanum lycopersicum , Brasil , Ecosistema , Monitoreo del Ambiente , Análisis de los Alimentos/métodos , Calentamiento Global
2.
J Food Sci ; 88(9): 3786-3806, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37493271

RESUMEN

This study aimed to evaluate coconut sugar (CS) as an alternative osmotic agent to sucrose for the osmotic dehydration (OD) of strawberries. OD was performed by immersing strawberries cut into 13.6 ± 0.4 mm edge cubes in osmotic solutions of CS or sucrose, at two different concentrations (40% and 60%, w/w), with and without application of vacuum (AV) in the first 20 min of the process. The total OD time was 300 min. Evaluations of the kinetics of solid gain (SG), water loss (WL), and weight reduction (WR) were performed at 30, 60, 120, 180, 240, and 300 min. SG, WL, and WR increased over the OD time and showed values of up to 7.94%, 63.40%, and 55.94%, respectively. AV increased WL, WR, shrinkage, pH, and total color difference and decreased anthocyanin, ascorbic acid (AA), phenolic, and antioxidant contents. The higher concentration led to higher SG, WL, WR, shrinkage, hardness, and lower moisture content, water activity, anthocyanin, AA, phenolic, and antioxidant contents. The use of CS instead of sucrose had little influence on strawberry properties, except pH and color responses. The optimal treatment was using a 60% CS solution without AV, showing a very distinct color change, hardness increased by approximately 4.5 times and maintenance of acidity, anthocyanins, AA, total phenolics, and antioxidants of 38.0%, 39.6%, 11.8%, 30.0%, 31.1%, and 30.3%, respectively, compared to fresh strawberries. PRACTICAL APPLICATION: Osmotic dehydration of fruit is a process traditionally carried out using sucrose. However, increasing health concerns have made consumers seek alternative sugars to sucrose. The use of coconut sugar made it possible to produce osmo-dehydrated strawberries different from the traditional one, maintaining product quality and process efficiency.


Asunto(s)
Antioxidantes , Fragaria , Antioxidantes/química , Fragaria/química , Antocianinas/análisis , Azúcares/análisis , Cocos , Deshidratación , Desecación , Ácido Ascórbico/análisis , Frutas/química , Sacarosa/análisis , Agua/análisis
3.
J Food Sci ; 87(9): 4056-4067, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35986622

RESUMEN

Spent coffee grounds (SCG) are a coproduct that causes environmental impacts worldwide. Thus, consciously reusing the SCG is an eminent need. This work aimed to encapsulate phenolic compounds and antioxidants obtained from SCG extracts through spray- and freeze-drying techniques using different isolated and combined wall materials. The dried powders produced were evaluated for moisture content, water activity, bulk density, hygroscopicity, color, content of phenolic compounds and antioxidants, and the results were compared. The results showed that all evaluated treatments resulted in a powdered product with low values of bulk density, moisture and water activity, especially for freeze-drying. The freeze-dried product also showed higher hygroscopicity. Regarding the content of phenolic compounds and antioxidants, both drying methods showed high levels of these compounds in the dried product and good encapsulation efficiency, reaching 83.43%. In most cases, spray-drying and freeze-drying did not differ statistically (p > 0.05) in relation to bioactive compound content and encapsulation efficiency. In relation to wall materials, albumin showed the worst performance in the retention of bioactive compounds. On the other hand, pure gum arabic combined with maltodextrin led to better preservation of these compounds. PRACTICAL APPLICATION: Spent coffee grounds are a coproduct generated in large quantities in the world. The encapsulation of phenolic and antioxidant compounds protects and enables their application in different food matrices. Therefore, the evaluation of different encapsulation methods and wall materials is important to define good process conditions.


Asunto(s)
Antioxidantes , Café , Albúminas , Antioxidantes/análisis , Goma Arábiga , Fenoles/análisis , Polvos , Agua
4.
Braz J Microbiol ; 40(3): 601-11, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24031405

RESUMEN

The nisin effect on thermal death of Alicyclobacillus acidoterrestris CRA 7152 spores in concentrated orange juice (64°Brix) was studied. Concentrations of 0, 50, 75 and 100 IU of nisin/ml juice, at temperatures of 92, 95, 98 and 102°C were evaluated. The quadratic polynomial model was used to analyze the effects of the factors and their interaction. Verification of surviving spores was carried out through plating in K medium (pH 3.7). The results showed that the D values without nisin addition were 25.5, 12.9, 6.1 and 2.3 min for 92, 95, 98 and 102°C respectively. With addition of nisin into the juice there was a drop of heat resistance as the concentration was increased at a same temperature. With 30, 50, 75, 100 and 150 IU/ml at 95°C, the D values were 12.34, 11.38, 10.49, 9.49 and 9.42 min respectively, showing that a decrease in the D value up to 27% can be obtained. The second order polynomial model established with r(2) = 0.995 showed that the microorganism resistance was affected by the action of temperature followed by the nisin concentration. Nisin therefore is an alternative for reducing the rigor of the A. acidoterrestris CRA 7152 thermal treatment.

5.
Arq Bras Endocrinol Metabol ; 51(4): 566-74, 2007 Jun.
Artículo en Portugués | MEDLINE | ID: mdl-17684617

RESUMEN

We studied clinical and laboratorial features of 73 patients with endogenous Cushing's syndrome, subdivided as follows: 46 (63%) with Cushing's disease (CD), 21 (28.7%) with an adrenal tumor and 6 (8.2%) with ectopic ACTH secretion (EAS). The rate of typical manifestations of hypercortisolism was similar regardless its etiology. In 100% of cases of Cushing's syndrome we observed serum cortisol levels greater than 1.8 microg/dL in low-dose dexamethasone (DMS) suppression tests, as well as elevation of serum or salivary midnight cortisol. However, urinary free cortisol was normal in 11.5% of patients. ACTH levels were suppressed in patients with adrenal tumors, normal or high in CD and always high in EAS. In the 8-mg overnight DMS suppression test, serum cortisol suppression > 50% was observed in 78.2% of cases of CD and in 33.3% of subjects with EAS, while an 80% suppression was only seen in CD. After stimulation with CRH or DDAVP an ACTH increase > 35% occurred in 81% of individuals with CD and 16.6% of those with EAS, while an ACTH increase > 50 achieved 100% specificity. Moreover, the combination of serum cortisol suppression > 50% and an ACTH increase > 35% in both tests only occurred in Cushing's disease. Pituitary magnetic resonance imaging identified 100% of macroadenomas and 59.4% of microadenomas in patients with CD. Among 10 patients that underwent bilateral inferior petrosal sinus sampling, a central-to-peripheral ACTH gradient > 3 after CRH or DDAVP had 90% sensitivity and 100% specificity for Cushing's disease.


Asunto(s)
Síndrome de ACTH Ectópico/diagnóstico , Síndrome de Cushing/diagnóstico , Dexametasona , Glucocorticoides , Hidrocortisona/sangre , Síndrome de ACTH Ectópico/etiología , Adenoma/diagnóstico , Adolescente , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Adulto , Niño , Preescolar , Síndrome de Cushing/etiología , Síndrome de Cushing/fisiopatología , Dexametasona/administración & dosificación , Diagnóstico Diferencial , Métodos Epidemiológicos , Femenino , Glucocorticoides/administración & dosificación , Humanos , Hidrocortisona/orina , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Factores Sexuales
6.
Arq Bras Endocrinol Metabol ; 51(1): 86-91, 2007 Feb.
Artículo en Portugués | MEDLINE | ID: mdl-17435860

RESUMEN

Macroprolactinemia is characterized by the predominance in the serum of macroprolactin, a prolactin (PRL) with high molecular mass and low biological activity that does not need treatment. The prevalence of macroprolactinemia was evaluated in 115 consecutive patients with hyperprolactinemia. Among them, 19 (16.5%) had solely macroprolactinemia, 4 (3.5%) polycystic ovary syndrome, 7 (6.1%) acromegaly, 8 (6.9%) idiopathic hyperprolactinemia, 10 (8.6%) primary hypothyroidism, 14 (12.2%) clinically non-functioning pituitary adenomas, 20 (17.4%) drug-induced hyperprolactinemia and 33 (28.7%) prolactinomas. The diagnosis of macroprolactinemia was established by the demonstration of a PRL recovery < 30% after treatment of sera with polyethylene glycol. Among the 19 patients with isolated macroprolactinemia, 16 (84.2%) were female and 12 (63.2%) were asymptomatic, while 4 (21%) presented with oligomenorrhea and 3 (15.8%) with galactorrhea. In contrast, only 11.5% of individuals with other causes of hyperprolactinemia were asymptomatic (p< 0.001). Prolactin levels in cases of macroprolactin ranged from 45.1 to 404 ng/mL (mean 113.3 +/- 94.5) but in 15 (78.9%) were < 100 ng/mL. Our findings demonstrate that macroprolactinemia is a common condition and, therefore, we suggest that it should be routinely screened in patients with hyperprolactinemia.


Asunto(s)
Hiperprolactinemia/epidemiología , Prolactina/sangre , Adulto , Análisis de Varianza , Biomarcadores/sangre , Brasil/epidemiología , Precipitación Química , Comorbilidad , Femenino , Humanos , Hiperprolactinemia/etiología , Mediciones Luminiscentes , Masculino , Persona de Mediana Edad , Polietilenglicoles , Prevalencia
7.
Disabil Rehabil ; 35(17): 1472-8, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23869824

RESUMEN

PURPOSE: Motor deficits in lower extremities and gait abnormalities are a major feature of the multiple sclerosis (MS) patients. Patients with minimal clinical disability have subtle gait changes. The aim of this study was to analyze the gait characteristics of MS patients in the absence of clinical disability. METHOD: A case-control study was carried out with 12 MS patients and 12 matched healthy controls. The subjects underwent a clinical neurological evaluation to determine their disability level (EDSS ≤ 1.5). Then, the subjects were referred for completion self-report questionnaires (gait, perceived balance confidence, physical activity and fatigue), gait clinical trials, and 3D kinematic analysis. RESULTS: MS patients showed more impairment of perceived fatigue, perceived of walking impact and perceived balance confidence, despite having no disability. Gait characteristics showed no differences when they were determined by clinical observation. The 3D kinematic analysis of gait showed slight but significant changes in ankle movement. CONCLUSION: MS patients with no clinical disability have discrete changes in gait that can be evidenced by perceived impact on walking and kinematic evaluation, mainly of ankle movement. Moreover, there is a decrease in perceived balance confidence and an increase in perceived fatigue, which are correlated despite having different origins.


Asunto(s)
Evaluación de la Discapacidad , Marcha/fisiología , Esclerosis Múltiple/fisiopatología , Adulto , Análisis de Varianza , Fenómenos Biomecánicos , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Esclerosis Múltiple/rehabilitación , Autoinforme
8.
J Food Sci ; 78(2): E222-8, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23317379

RESUMEN

UNLABELLED: Peroxidase activity accounts for quality losses in many plant-based foods. The paper provides insight into the inactivation kinetics of peroxidase (POD) in carrot juice treated with pulsed electric fields (PEF). Juice samples were subjected to electric field intensities of 20 to 35 kV/cm for 300 to 2000 µs. Up to 93% of the initial activity was inactivated after treating at 35 kV/cm for 1500 µs. POD activity inactivation correlated well with the increase in energy density input. A first-order fractional conversion model best fitted the experimental results. Other kinetic approaches such as the Fermi's model can be used to estimate residual POD activity values in treated juices as a function of electric field strength. PRACTICAL APPLICATION: Pulsed electric fields (PEF) are a processing technology that can be used for the pasteurization of liquid food products. Peroxidase activity inhibition is required in carrot juices to prevent undesirable quality losses, such as discoloration, flavor changes, and loss of nutrients. The most significant processing parameters ruling POD inactivation in PEF-treated carrot juice are identified and mathematical modeling of experimental data is conducted.


Asunto(s)
Bebidas/análisis , Daucus carota/enzimología , Manipulación de Alimentos/métodos , Peroxidasa/metabolismo , Electricidad , Cinética , Modelos Teóricos , Dinámicas no Lineales , Pasteurización , Peroxidasa/antagonistas & inhibidores
9.
Artículo en Portugués | LILACS | ID: biblio-987613

RESUMEN

Efetuou-se revisão de literatura sobre a utilização da radiação ionizante como forma de conservação de alimentos. Foram abordados tópicos como sua evolução histórica, o princípio de funcionamento dos equipamentos, suas diferentes áreas de aplicação e, principalmente, sua utilização na conservação de alimentos. São apresentados os resultados de estudos realizados com o objetivo de verificar a eficiência da radiação ionizante na eliminação de vários micro-organismos em diversos produtos e o efeito da radiação ionizante nas características sensoriais e nutricionais dos alimentos. Apesar de já ter sido comprovada a segurança da aplicação da radiação ionizante em alimentos, da sua utilização ser permitida em diversos países e de ser cientificamente aceita como excelente método de conservação de alimentos, o progresso no seu uso comercial tem sido lento face às interpretações errôneas dos consumidores e à falta de informações sobre o uso dessa tecnologia.


Asunto(s)
Radiación Ionizante , Conservación de Alimentos , Tecnología de Alimentos
10.
Ciênc. rural ; 42(5): 934-941, maio 2012.
Artículo en Portugués | LILACS | ID: lil-626325

RESUMEN

Campos elétricos pulsados de alta intensidade (CEPAI) constituem um método não-térmico de conservação para alimentos em substituição à pasteurização tradicional. Em comparação ao processamento térmico, os CEPAI, além de serem eficientes na eliminação de micro-organismos e na inativação de enzimas, também minimizam as perdas de sabor, cor, textura, nutrientes e componentes termolábeis dos alimentos. O objetivo desse trabalho foi levantar dados bibliográficos atuais sobre o tema CEPAI, abordando: definição do processo, instalação experimental, efeito da ruptura dielétrica do alimento, efeito sobre micro-organismo, enzimas e constituintes dos alimentos. Os dados encontrados na literatura apontam o tratamento por CEPAI como alternativa promissora para a conservação de alimentos, podendo ser utilizado como tecnologia única ou como complemento aos processamentos térmicos.


Pulsed electric fields of high intensity (HIPEF) is a non-thermal food conservation to replace traditional thermal pasteurization. Compared to thermal processing, the HIPEF as well as being effective in removing microorganisms and inactivate enzymes also minimize the loss of flavor, color, texture, nutrients and labile components of food. The aim of this work was to gather bibliographic data current HIPEF on the subject, covering: experimental setup, effects of dielectric breakdown of food, effect on microorganisms, enzymes and constituents of food. The data found in the literature indicate treatment of HIPEF as a promising alternative for food conservation and it could be used as a single technology or in addition to thermal processing.

11.
Rev. Inst. Adolfo Lutz ; 69(2): 188-193, abr.-jun. 2010. tab, graf
Artículo en Portugués | LILACS, SES-SP, SES SP - Publicações científico-técnicas, SES-SP, SESSP-ACVSES, SES SP - Instituto Adolfo Lutz, SES-SP, SESSP-IALACERVO | ID: lil-571138

RESUMEN

Este trabalho teve como objetivo determinar o teor total de fibras alimentares em polpa da raiz (PRY) e de farinha de yacon (FY) pelo método enzimático-gravimétrico segundo AOAC e os frutanos por cromatografia líquida de alta eficiência (HPLC). A FY foi preparada por meio do processo de limpeza, sanitização, branqueamento e a secagem da PRY a 55°C por 48 horas. Foi determinada a composição centesimal da FYe da PRY; o teor de fibras totais correspondeu ao somatório das determinações pelo método enzimático gravimétrico e HPLC. Encontrou-se elevado teor de fibra alimentar total (matéria seca) nas amostras de PRYe de FY (33,14 e 50,76%, respectivamente), com predomínio de frutooligossacarídeos [FOS] (37,97 e 40,97% respectivamente) e considerável teor de inulina (26,10 e 20,75%, respectivamente). O cromatograma também mostrou elevada concentração de frutose, glicose e sacarose como únicas fontes de carboidratos, além dos frutanos, inulina e FOS. Os métodos enzimático-gravimétricos são considerados os mais apropriados para análises rotineiras de fibras alimentares, contudo estes são ineficazes para determinação de oligossacarídeos com grau de polimerização menor do que 12, como é o yacon. Assim, é necessário efetuar métodos complementares, como HPLC, para quantificar com exatidão o teor total de fibra alimentar dessa raiz.


This study aimed at determining the total dietary fiber contents in yacon root pulp (YRP) and yacon flour (YF) by the AOAC enzymatic-gravimetric method, and fructans by high performance liquid chromatography (HPLC). The YF was put through the process of cleaning, sanitizing, bleaching, and YRP was dried at 55 °C for 48 hours. The chemical composition of the YF and YRP was determined, being the total fiber contents the sum of the determinations by enzymatic-gravimetric method and HPLC. High contents of total dietaryfiber were detected in the dry mater of both YRP and YF samples (33.14 and 50.76%, respectively), being mostly fructooligosaccharides [FOS] (37.97 and 40.97%, respectively), and substantial inulin contents (26.10 and 20.75%, respectively). The chromatogram also showed high contents of fructose, glucose and sucrose as the sole source of carbohydrates besides fructans, inulin and FOS. The enzymatic-gravimetric methods are considered the most suitable for routine analysis of dietary fibers, but are ineffective for determining oligosaccharides with polymerization degree less than 12, as yacon. Thus, a complementary method, such as HPLC, needs to be carried out to quantify the exacting dietary fiber contents in this root.


Asunto(s)
Fibras de la Dieta , Inulina , Oligosacáridos
12.
Braz. j. microbiol ; 40(3): 601-611, Sept. 2009. ilus, tab
Artículo en Inglés | LILACS | ID: lil-522481

RESUMEN

The nisin effect on thermal death of Alicyclobacillus acidoterrestris CRA 7152 spores in concentrated orange juice (64ºBrix) was studied. Concentrations of 0, 50, 75 and 100 IU of nisin/ml juice, at temperatures of 92, 95, 98 and 102ºC were evaluated. The quadratic polynomial model was used to analyze the effects of the factors and their interaction. Verification of surviving spores was carried out through plating in K medium (pH 3.7). The results showed that the D values without nisin addition were 25.5, 12.9, 6.1 and 2.3 min for 92, 95, 98 and 102ºC respectively. With addition of nisin into the juice there was a drop of heat resistance as the concentration was increased at a same temperature. With 30, 50, 75, 100 and 150 IU/ml at 95ºC, the D values were 12.34, 11.38, 10.49, 9.49 and 9.42 min respectively, showing that a decrease in the D value up to 27 percent can be obtained. The second order polynomial model established with r² = 0.995 showed that the microorganism resistance was affected by the action of temperature followed by the nisin concentration. Nisin therefore is an alternative for reducing the rigor of the A. acidoterrestris CRA 7152 thermal treatment.


Estudou-se o efeito da nisina na inativação térmica dos esporos de Alicyclobacillus acidoterrestris CRA 7152 em suco de laranja concentrado (64 ºBrix). Foram avaliadas as concentrações de 0, 50, 75 e 100 UI de nisina/ml de suco nas temperaturas de 92, 95, 98 e 102 ºC. Foi utilizado o modelo polinomial quadrático para analisar os efeitos dos fatores e suas interações. A contagem dos esporos sobreviventes foi feita através de plaqueamento em meio K (pH = 3,7). De acordo com os resultados obtidos encontrouse um valor de D sem adição de nisina de 25,5; 12,9; 6,1 e 2,3 min para as temperaturas de 92, 95, 98 e 102 ºC respectivamente. Quando a nisina foi adicionada ao suco observouse uma queda na resistência térmica em função do aumento da concentração de nisina para os mesmos valores de temperatura. Ao utilizar as concentrações de 30, 50, 75 e 150 IU/ml a 95 ºC, o valor de D obtido foi de 12,34; 11,38; 10,49; 9,49; e 9,42 min respectivamente demonstrando que a adição de nisina provoca um decréscimo de até 27 por cento no valor de D. O modelo polinomial de segunda ordem ajustado com r² = 0,995 mostrou que a resistência do microorganismo foi afetada pela temperatura seguida da concentração de nisina. A adição de nisina é, portanto, uma alternativa para reduzir o rigor do tratamento térmico em A. acidoterrestris CRA 7152.

13.
ACM arq. catarin. med ; 38(3)jul.-set. 2009.
Artículo en Portugués | LILACS | ID: lil-663087

RESUMEN

Este trabalho teve como objetivo compreender aprática da meditação e sua aplicabilidade na área dasaúde, através de uma revisão da literatura nacional einternacional. Para isso, foram feitas buscas em revistasespecializadas, livros e nos bancos de dados da ScienceDirect e PubMed, do período de 1985 a 2007, utilizandosea palavra-chave ?meditation?. Além disso, foirealizada uma nova busca e análise crítica sobre ostrabalhos encontrados nos mesmos bancos de dados doperíodo de 2002 a 2008, utilizando-se o cruzamento daspalavras-chave ?meditation? e ?hypertension?. Dadosencontrados demonstraram a eficácia da meditação naredução da pressão arterial sistólica (PAS) e pressãoarterial diastólica (PAD), entretanto também foramencontradas falhas metodológicas que podem tercomprometido os resultados destes trabalhos.


This work had as objective to understand the practiceof meditation and it?s applicability in the health area,through a review of national and international literature.To do this, searches were made in journals, books anddatabases like Science Direct and PubMed, from theperiod of 1985 to 2007, using the keyword ?meditation?.In addition, was conducted a new search and review ofwork?s that wore found in the same databases from theperiod of 2002 to 2008, using the intersection of the keywords ?meditation? and ?hypertension?. Obtained datashowed the effectiveness of meditation in reducingsystolic and diastolic blood pressure, however also foundmethodological failures that may have affected the resultsof the works.

14.
Biochemistry ; 42(30): 9022-7, 2003 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-12885235

RESUMEN

Alzheimer's disease, Parkinson's disease, cystic fibrosis, prion diseases, and many types of cancer are considered to be protein conformation diseases. Most of them are also known as amyloidogenic diseases due to the occurrence of pathological accumulation of insoluble aggregates with fibrillar conformation. Some neuroblastomas, carcinomas, and myelomas show an abnormal accumulation of the wild-type tumor suppressor protein p53 either in the cytoplasm or in the nucleus of the cell. Here we show that the wild-type p53 core domain (p53C) can form fibrillar aggregates after mild perturbation. Gentle denaturation of p53C by pressure induces fibrillar aggregates, as shown by electron and atomic force microscopies, by binding of thioflavin T, and by circular dichroism. On the other hand, heat denaturation produced granular-shaped aggregates. Annular aggregates similar to those found in the early aggregation stages of alpha-synuclein and amyloid-beta were also observed by atomic force microscopy immediately after pressure treatment. Annular and fibrillar aggregates of p53C were toxic to cells, as shown by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] reduction assay. Interestingly, the hot-spot mutant R248Q underwent similar aggregation behavior when perturbed by pressure or high temperature. Fibrillar aggregates of p53C contribute to the loss of function of p53 and seed the accumulation of conformationally altered protein in some cancerous cells.


Asunto(s)
Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/ultraestructura , Animales , Línea Celular , Calor , Humanos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Microscopía de Fuerza Atómica , Microscopía Electrónica , Oxidación-Reducción/efectos de los fármacos , Presión , Desnaturalización Proteica , Pliegue de Proteína , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Sales de Tetrazolio/metabolismo , Tiazoles/metabolismo , Proteína p53 Supresora de Tumor/toxicidad
15.
Artif Organs ; 27(5): 447-51, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12752206

RESUMEN

This work presents different applications in progress with the aid of the atomic force microscopy (AFM) technique for biomedical and biotechnological applications, comprising both the acquisition of three-dimensional images and spectroscopic force measurements, in the following systems: first, low-density lipoprotein (LDL)-glycosaminoglycans; second, lectins-polysaccharides; third, mycobacterium leprae cellular wall and Vesicular Stomatites Virus (VSV) with fibronectin laminin, and lipidic membranes; fourth, DNA-complex; and fifth, actin, as well as the development of surface functionalizing protocols and image restoration by means of mathematical techniques.


Asunto(s)
Microscopía de Fuerza Atómica/métodos , Tecnología Biomédica , Biología Celular/instrumentación , Procesamiento de Imagen Asistido por Computador/instrumentación , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional , Propiedades de Superficie
17.
Arq. bras. endocrinol. metab ; 51(1): 86-91, fev. 2007. graf, tab
Artículo en Portugués | LILACS | ID: lil-448368

RESUMEN

Macroprolactinemia caracteriza-se pelo predomínio no soro de uma prolactina (PRL) de alto peso molecular e baixa atividade biológica que não requer tratamento. A prevalência de macroprolactinemia foi avaliada em 115 pacientes consecutivos com hiperprolactinemia. Entre eles, 19 (16,5 por cento) tinham exclusivamente macroprolactinemia, 4 (3,5 por cento) síndrome dos ovários policísticos, 7 (6,1 por cento) acromegalia, 8 (6,9 por cento) hiperprolactinemia idiopática, 10 (8,7 por cento) hipotiroidismo primário, 14 (12,2 por cento) adenomas clinicamente não-funcionantes, 20 (17,4 por cento) hiperprolactinemia farmacológica e 33 (28,7 por cento) prolactinomas. O diagnóstico de macroprolactinemia foi estabelecido pela obtenção de uma recuperação da PRL < 30 por cento após tratamento do soro com polietilenoglicol. Dentre os 19 pacientes com macroprolactinemia isolada, 16 (84,2 por cento) eram mulheres e 12 (63,2 por cento) eram assintomáticos, enquanto 4 (21 por cento) tinham oligomenorréia e 3 (15,8 por cento), galactorréia. Em contraste, apenas 11,5 por cento dos indivíduos com outras causas de hiperprolactinemia eram assintomáticos (p< 0,001). Os níveis de PRL nos casos de macroprolactinemia variaram de 45,1 a 404 ng/mL (média de 113,3 ± 94,5), mas em 15 (78,9 por cento) foram < 100 ng/mL. Nossos achados demonstram que macroprolactinemia é uma condição freqüente e, assim, sugerimos que seja rotineiramente pesquisada em pacientes com hiperprolactinemia.


Macroprolactinemia is characterized by the predominance in the serum of macroprolactin, a prolactin (PRL) with high molecular mass and low biological activity that does not need treatment. The prevalence of macroprolactinemia was evaluated in 115 consecutive patients with hyperprolactinemia. Among them, 19 (16.5 percent) had solely macroprolactinemia, 4 (3.5 percent) polycystic ovary syndrome, 7 (6.1 percent) acromegaly, 8 (6.9 percent) idiopathic hyperprolactinemia, 10 (8.6 percent) primary hypothyroidism, 14 (12.2 percent) clinically non-functioning pituitary adenomas, 20 (17.4 percent) drug-induced hyperprolactinemia and 33 (28.7 percent) prolactinomas. The diagnosis of macroprolactinemia was established by the demonstration of a PRL recovery < 30 percent after treatment of sera with polyethylene glycol. Among the 19 patients with isolated macroprolactinemia, 16 (84.2 percent) were female and 12 (63.2 percent) were asymptomatic, while 4 (21 percent) presented with oligomenorrhea and 3 (15.8 percent) with galactorrhea. In contrast, only 11.5 percent of individuals with other causes of hyperprolactinemia were asymptomatic (p< 0.001). Prolactin levels in cases of macroprolactin ranged from 45.1 to 404 ng/mL (mean 113.3 ± 94.5) but in 15 (78.9 percent) were < 100 ng/mL. Our findings demonstrate that macroprolactinemia is a common condition and, therefore, we suggest that it should be routinely screened in patients with hyperprolactinemia.


Asunto(s)
Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hiperprolactinemia/epidemiología , Prolactina/sangre , Análisis de Varianza , Biomarcadores/sangre , Brasil/epidemiología , Precipitación Química , Comorbilidad , Hiperprolactinemia/etiología , Mediciones Luminiscentes , Prevalencia , Polietilenglicoles
18.
Arq. bras. endocrinol. metab ; 51(4): 566-574, jun. 2007. tab
Artículo en Portugués | LILACS | ID: lil-457093

RESUMEN

Avaliamos as características clínico-laboratoriais de 73 pacientes com síndrome de Cushing (SC) endógena, assim distribuídos: 46 (63 por cento) com doença de Cushing (DC), 21 (28,7 por cento) com tumores adrenais (TA) e 6 (8,2 por cento) com a síndrome do ACTH ectópico (SAE). A freqüência de manifestações clássicas do hipercortisolismo foi similar, independentemente da etiologia da SC. Em 100 por cento dos casos de SC, observaram-se níveis do cortisol sérico (CS) > 1,8 µg/dL após supressão com doses baixas de dexametasona (DMS), além de elevação do cortisol à meia-noite (sérico ou salivar). Contudo, o cortisol livre urinário foi normal em 11,5 por cento dos pacientes. Os níveis de ACTH mostraram-se suprimidos nos pacientes com TA, normais ou elevados na DC e sempre elevados na SAE. No teste de supressão noturna com 8 mg de DMS, supressão do CS > 50 por cento foi observada em 78,2 por cento dos casos de DC e 33,3 por cento dos casos de SAE, enquanto uma supressão > 80 por cento foi exclusiva da DC. Após estímulo com CRH ou DDAVP, um incremento do ACTH > 35 por cento aconteceu em 81 por cento dos indivíduos com DC e em 16,6 por cento daqueles com SAE, ao passo que um incremento do ACTH > 50 por cento restringiu-se à DC. A combinação de incremento do ACTH > 35 e supressão do CS > 50 por cento foi também exclusiva da DC. A ressonância magnética visualizou 100 por cento dos macroadenomas e 59,4 por cento dos microadenomas hipofisários nos casos de DC. Em 10 pacientes submetidos ao cateterismo bilateral do seio petroso inferior, um gradiente centro-periferia de ACTH > 3 pós-CRH ou DDAVP teve sensibilidade de 90 por cento e especificidade de 100 por cento para a doença de Cushing.


We studied clinical and laboratorial features of 73 patients with endogenous Cushings syndrome, subdivided as follows: 46 (63 percent) with Cushings disease (CD), 21 (28.7 percent) with an adrenal tumor and 6 (8.2 percent) with ectopic ACTH secretion (EAS). The rate of typical manifestations of hypercortisolism was similar regardless its etiology. In 100 percent of cases of Cushings syndrome we observed serum cortisol levels greater than 1.8 µg/dL in low-dose dexamethasone (DMS) suppression tests, as well as elevation of serum or salivary midnight cortisol. However, urinary free cortisol was normal in 11.5 percent of patients. ACTH levels were suppressed in patients with adrenal tumors, normal or high in CD and always high in EAS. In the 8-mg overnight DMS suppression test, serum cortisol suppression > 50 percent was observed in 78.2 percent of cases of CD and in 33.3 percent of subjects with EAS, while an 80 percent suppression was only seen in CD. After stimulation with CRH or DDAVP an ACTH increase > 35 percent occurred in 81 percent of individuals with CD and 16.6 percent of those with EAS, while an ACTH increase > 50 achieved 100 percent specificity. Moreover, the combination of serum cortisol suppression > 50 percent and an ACTH increase > 35 percent in both tests only occurred in Cushings disease. Pituitary magnetic resonance imaging identified 100 percent of macroadenomas and 59.4 percent of microadenomas in patients with CD. Among 10 patients that underwent bilateral inferior petrosal sinus sampling, a central-to-peripheral ACTH gradient > 3 after CRH or DDAVP had 90 percent sensitivity and 100 percent specificity for Cushings disease.


Asunto(s)
Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome de ACTH Ectópico/diagnóstico , Síndrome de Cushing/diagnóstico , Dexametasona , Glucocorticoides , Hidrocortisona/sangre , Síndrome de ACTH Ectópico/etiología , Adenoma/diagnóstico , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Síndrome de Cushing/etiología , Síndrome de Cushing/fisiopatología , Diagnóstico Diferencial , Dexametasona/administración & dosificación , Métodos Epidemiológicos , Glucocorticoides/administración & dosificación , Hidrocortisona/orina , Imagen por Resonancia Magnética , Sensibilidad y Especificidad , Factores Sexuales
19.
Rev. bras. ginecol. obstet ; 28(3): 151-157, mar. 2006. ilus, tab
Artículo en Portugués | LILACS | ID: lil-447891

RESUMEN

OBJETIVO: além da ausência ultra-sonográfica do osso nasal fetal, sua hipoplasia também apresenta forte associação com a trissomia 21, porém por não haver clara definição do que seja tal hipoplasia, objetivou-se estabelecer seus valores de referência ao longo da gestação, em população brasileira. MÉTODOS: este estudo seccional se baseou em 625 dentre 902 fetos, entre 10 e 39 semanas, considerando-se uma medida de cada indivíduo. Foram excluídos os malformados e aqueles cujas mães apresentavam doenças que, sabidamente, interferem em seu crescimento. Utilizou-se a imagem ecográfica do perfil fetal, com feixe acústico incidindo em ângulo de 45 ou 135° em relação ao plano da face. A média de cada idade gestacional foi estimada pela regressão polinomial. O teste de Anderson-Darling verificou a distribuição normal das medidas (p>0,05). RESULTADOS: dos 625 fetos, 88,3 por cento originaram-se de gestações simples e 11,7 por cento de gestações múltiplas. O avanço da idade gestacional implicou aumento da medida do osso nasal e aumento de sua variabilidade. Encontrou-se tamanho mínimo de 1,0 mm e 4,7 mm no primeiro e segundo trimestres, respectivamente. CONCLUSÕES: há correlação direta entre o tamanho do osso nasal e a idade gestacional. Essa correlação é válida tanto para gestação simples quanto para múltipla. Este trabalho permite adotar a avaliação ecográfica do osso nasal fetal como marcador de cromossomopatias, ao estabelecer os valores de referência de sua medida ao longo da gestação, útil para a população brasileira, com grande miscigenação étnica. Entretanto, necessita-se aprimorar a sistematização e padronização do estudo ecográfico do osso nasal fetal, além de estabelecer seu real valor em fetos previamente classificados como de alto e baixo risco para aneuploidias.


PURPOSE: the absence of fetal nasal bone is correlated with trisomy 21. Although a hypoplastic nasal bone is also correlated with trisomy 21, there is no clear definition of this term in the literature. Our objective was to establish the reference values for fetal nasal bone size throughout gestation in a local population in Brazil. METHODS: it is a cross-sectional study on 902 fetuses at 10 to 39 weeks of gestation. After having excluded fetal malformations and maternal diseases which are known to interfere with fetal growth, 625 fetuses were selected. We obtained a mid-sagittal view of the fetal profile by holding the ultrasound bean at an angle of 45° or 135°. The nasal bone size mean was calculated by using polynomial regression. The Anderson-Darling test proved the normal distribution of the measurements (p>0.05). RESULTS: of the 625 fetuses, 88.3 percent were from single gestations and 11.7 percent from multiple ones. There was a direct correlation between fetal nasal bone size and gestational age. The variability of nasal bone size became larger as gestational age increased. Minimal length of 1.0 and 4.7 mm in the first and second trimesters, respectively, were found. CONCLUSIONS: there is a direct correlation between fetal nasal bone size and gestational age. This correlation is valid either for a single gestation or a multiple one. These measurements of the fetal nasal bone will allow us to use them as a screening test for cromosomal abnormalities. This is a useful study if we consider the large miscegenation of the Brazilian population. However, further systematic and standardized approach to study the fetal nasal bone is needed to establish its real value in fetuses once classified as at high or low risk for aneuploidies.


Asunto(s)
Humanos , Femenino , Embarazo , Aneuploidia , Síndrome de Down , Hueso Nasal , Valores de Referencia , Ultrasonografía Prenatal
20.
Bol. Centro Pesqui. Process. Aliment ; 23(2): 329-346, jul.-dez. 2005. tab, graf
Artículo en Portugués | LILACS | ID: lil-423814

RESUMEN

Neste trabalho objetivou-se estabelecer a proporção de banana, a composição da solução extratora, bem como o tempo de extração para produzir licor com qualidade. Efetuou-se experimento fatorial com tres quantidades de polpa de banana (500, 800 e 1100 g de banana para produção de 4 L de licor) e dois teores alcoólicos da solução extratora (70 e 95ºGL). O processo de extração foi estudado durante 21 dias em que se analisaram as coordenadas de cor, pH, teor de sólidos solúveis e dendidade a 20ºC do extrato. O licor jovem foi caracterizado e submetido à análise sensorial após 45 dias de envelhecimento. O tempo de 16 dias mostrou-se suficiente para finalizar a etapa de extração, evidenciando que o tempo de infusão deve ser de 15 a 16 dias. A solução extratora com teor alcoólico de 95ºGL apresentou melhores resultados, principalmente no que se refere à cor final do produto e facilidade na filtração. Como não houve diferença significativa entre as quantidades de polpa de banana optou-se pela menor proporção em razão de fatores econômicos. Portanto, a utilização de 500 g de polpa de banana é suficiente para produzir 4 L de licor


Asunto(s)
Bebidas , Manipulación de Alimentos , Tecnología de Alimentos , Musa
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