Biomarcadores de luteína, zeaxantina y otros carotenoides en la relación dieta y salud ocular humana

El estudio de la relación entre componentes de la dieta y la salud/enfermedad utiliza métodos de valoración de la ingesta dietética, del estatus nutricional y de marcadores de función o de efecto. En concreto, en el estudio de los carotenoides y la salud ocular, interesa el estudio de dos carotenoides sin actividad provitamina A, la luteína y la zeaxantina, por su posible papel en la optimización de la función visual y en la prevención de enfermedades crónicas asociadas a la edad, y de tres carotenoides con actividad provitamina A: -caroteno, -caroteno y -criptoxantina, por ser precursores de retinol, nutriente del que depende el ciclo visual para una visión normal. En el presente trabajo se ha llevado a cabo el estudio de los carotenoides de la dieta más relevantes para la salud ocular humana considerando de forma simultánea parámetros relacionados con la ingesta, el estatus y la función visual, así como diversas variables que pueden modificar el estatus nutricional, como son la concentración de lípidos en sangre, y la bioaccesibilidad de los carotenoides a partir de alimentos de amplio consumo...

¿Qué son los microARNs?: posibles biomarcadores y dianas terapéuticas en la enfermedad osteoporótica

Los micro-ARN (miRs) son pequeñas moléculas de ARN no codificantes que regulan la expresión génica a nivel post-transcripcional. Generalmente actúan sobre la expresión genética mediante el silenciamiento o degradación de los ARNm, y están implicados en la regulación de varios procesos biológicos, como la diferenciación celular, la proliferación, la apoptosis y en el desarrollo embrionario y tisular. Actualmente son un importante foco de interés para el estudio de diversas enfermedades como el cáncer o la diabetes mellitus tipo 2. A nivel del metabolismo óseo, están surgiendo diversos miRs implicados en su regulación, abriendo un campo de investigación importante para identificar nuevos biomarcadores para el diagnóstico de la enfermedad osteoporótica, de su evolución, así como para diseñar nuevas terapias farmacológicas.

Análise de compostos orgânicos voláteis (BTEX) no ar da Cidade de Évora

A poluição atmosférica é um dos principais factores de degradação da qualidade de vida da população. O conjunto BTEX (benzeno, tolueno, etilbenzeno e xilenos) constitui o grupo mais importante dos compostos orgânicos voláteis (VOCs) na atmosfera uma vez que participam na química da atmosfera e constituem um perigo para a saúde, nomeadamente o benzeno, por ser altamente cancerígeno. São maioritariamente libertados pelo tráfego automóvel. Neste trabalho foi determinada a concentração dos BTEX em nove pontos da cidade de Évora no período de 21 Março a 1 de Julho de 2009 tendo-se recorrido à técnica de amostragem passiva, com amostradores Radiello™, seguida de desadsorção líquida, usando CS2, e subsequente análise por GC-MS. A concentração de benzeno no ar da cidade de Évora não excedeu o valor legislado de 5 g/m3 neste período de amostragem, sendo as concentrações obtidas para os poluentes em geral muito baixas e na sua maioria inferiores ao LOQ do método analítico. ABSTRACT; Air pollution is the major factor in the degradation of the population quality of life. BTEX (benzene, toluene, ethylbenzene and xylenes) is the most important group of volatile organic compounds (VOCs) in the atmosphere because of their role in atmospheric chemistry and the risk they posed to human health, with benzene, being a highly carcinogenic compound. BTEX are released mainly by road traffic. Concentrations of BTEX were determined at nine sampling points in the city of Évora in the period from 21 March to 1 July 2009, using passive samplers Radiello™, followed by liquid desorption with CS2, and subsequent analysis by GC-MS. During the sampling period, the concentration of benzene in the outdoor air of Évora city did not exceed 5 g/m3, the maximum value admissible by legislation. The concentrations measured of the other pollutants were, in general, very low and mostly below the LOQ of the analytical method.

Fenóis voláteis em vinhos tintos

As leveduras Dekkera/Brettanomyces são responsáveis pela formação de fenóis voláteis em vinhos tintos, tornando-se numa grande preocupação para a produção enológica a nível mundial, devido à dificuldade em controlá-las. Os fenóis voláteis são responsáveis por aromas desagradáveis nos vinhos tintos, diminuindo a sua qualidade e resultando em grandes perdas económicas. Este trabalho teve como principal objectivo estudar um método de preparação de amostra e um método cromatográfico para analisar e quantificar os principais fenóis voláteis (4-etilfenol, 4-etilguaiacol, 4-etilcatecol, 4-vinilfenol e o 4-vinilguaiacol), em meio sintético e em vinhos tintos comerciais. A preparação de amostras foi efectuada através do método de extracção líquido-líquido e a separação dos compostos foi efectuada por cromatografia gasosa com detector de ionização de chama (GC-FID). Os resultados obtidos permitem concluir que é possível detectar e quantificar os fenóis voláteis com este método, incluindo o 4-etilcatecol. O 4-etilfenol foi o composto mais abundante nos vinhos tintos comerciais estudados. ABSTRACT: The yeasts Dekkera I Brettanomyces are responsible for the formation of volatile phenols in red wine, becoming a major concern for the enological production worldwide because of the difficulty in controlling them. The volatile phenols are responsible for unpleasant aromas in red wines, reducing its quality and resulting in great economic lasses. The main objective of this work was to study a sample preparation and a chromatographic method to analyze main volatile phenols (4-ethylphenol, 4-ethylguaiacol, 4-ethylcatechol, 4-vinylphenol and 4-vinylguaiacol) in synthetic wine and red wines. Sample preparation was done by liquid-liquid extraction and compounds separation was achieved by gas chromatography with flame ionization detector (GC­ FID) Results showed that it is possible to detect and quantified volatile phenols with the methodology proposed, including 4-ethylcatechol. 4-ethylphenol was the main compound found in commercial red wines.

Relación de biomarcadores de dosis interna con síntomas neurológicos y de conducta en pintores de carros de la ciudad de Bogotá, 2015

Introducción: El uso de solventes orgánicos es muy frecuente en diferentes industrias y sectores económicos a nivel mundial, estos generan una importante exposición ocupacional asociándose con efectos mutagénicos, carcinógenos, teratogénicos y otros trastornos principalmente de tipo neurológico y de conducta. Objetivo: Determinar la relación entre la presencia de biomarcadores de dosis interna para solventes orgánicos y la existencia de síntomas neurológicos y de conducta en pintores de carros de la ciudad de Bogotá. Materiales y Métodos: Estudio de corte transversal una muestra de 122 individuos, 62 expuestos y 60 en el grupo control. Se incluyeron variables sociodemográficas, ocupacionales, clínicas y los resultados de biomarcadores en orina para benceno, tolueno y xileno (ácido S-fenilmercapturico, ácido hipúrico y orto, para y meta-metilhipúrico respectivamente). Para el análisis de la información se obtuvieron medidas de tendencia central y dispersión. Se utilizó análisis de correlación de Spearman y la prueba Chi cuadrado de asociación para establecer la relación entre la exposición ocupacional y los síntomas presentes obtenidos de la aplicación del cuestionario Q 16. El nivel de significación para las pruebas fue 0.05. Resultados: Los valores del ácido hipúrico estuvieron por encima de los límites permisibles en 17,74% (11) de los trabajadores y los de ácido p-metilhipúrico en el 12,90% (8) de ellos. No se registraron valores de ácido fenil-mercaptúrico por fuera del límite permitido. El 25% (15) de la población expuesta manifestó síntomas neurológicos. Se encontró una relación significativa entre los siguientes síntomas y la presencia de biomarcadores: ácido hipúrico y somnolencia (p=0.009), perdida del deseo sexual (p= 0 .019); ácido metilhipúrico y olvida hacer cosas importantes (p=0 .019), pérdida de fuerza en brazos o piernas (p= 0.013) e insomnio (p= 0.028); ácido fenil-mercaptúrico y alucinaciones (p= 0.000). Dos síntomas tuvieron una relación significativa tanto para el ácido hipúrico como para el ácido metilhipúrico: anormalmente cansado (p= 0.001 y 0.046) y dificultad para abotonarse (p= 0.045 y 0.002). Conclusiones. La presencia de síntomas neurológicos y de conducta son indicadores importantes de la exposición a solventes orgánicos. La aparición y detección temprana de estos permitirán establecer medidas de promoción y prevención al igual que programas de vigilancia epidemiológica.

Inflammation markers in healthy and periodontitis patients: a preliminary data screening

Advances in diagnostic research are moving towards methods whereby the periodontal risk can be identified and quantified by objective measures using biomarkers. Patients with periodontitis may have elevated circulating levels of specific inflammatory markers that can be correlated to the severity of the disease. The purpose of this study was to evaluate whether differences in the serum levels of inflammatory biomarkers are differentially expressed in healthy and periodontitis patients. Twenty-five patients (8 healthy patients and 17 chronic periodontitis patients) were enrolled in the study. A 15 mL blood sample was used for identification of the inflammatory markers, with a human inflammatory flow cytometry multiplex assay. Among 24 assessed cytokines, only 3 (RANTES, MIG and Eotaxin) were statistically different between groups (p<0.05). In conclusion, some of the selected markers of inflammation are differentially expressed in healthy and periodontitis patients. Cytokine profile analysis may be further explored to distinguish the periodontitis patients from the ones free of disease and also to be used as a measure of risk. The present data, however, are limited and larger sample size studies are required to validate the findings of the specific biomarkers.

A method to determine volatile contaminants in polyethylene terephthalate (PET) packages by HDC-GC-FID and its application to post-consumer materials

A simple and low cost method to determine volatile contaminants in post-consumer recycled PET flakes was developed and validated by Headspace Dynamic Concentration and Gas Chromatography-Flame Ionization Detection (HDC-GC-FID). The analytical parameters evaluated by using surrogates include: correlation coefficient, detection limit, quantification limit, accuracy, intra-assay precision, and inter-assay precision. In order to compare the efficiency of the proposed method to recognized automated techniques, post-consumer PET packaging samples collected in Brazil were used. GC-MS was used to confirm the identity of the substances identified in the PET packaging. Some of the identified contaminants were estimated in the post-consumer material at concentrations higher than 220 ng.g-1. The findings in this work corroborate data available in the scientific literature pointing out the suitability of the proposed analytical method.

Quality of sausage elaborated using minced Nile Tilapia submmitted to cold storage

Filleting yield of Nile tilapia Oreochromis niloticus (L.) is low (30%) and generates large amount of wastes that may turn into environmental and economic problem. However, these wastes can be used for the extraction of minced fish (MF) which can be used in the preparation of sausages. The objective of this study was to assess the quality of sausages prepared with 0, 20, 40, 60, 80 and 100% of MF from Nile tilapia filleting waste during storage at 0±0.3ºC. Alterations in the instrumental color (L*, a* and b*), lipid oxidation (TBARS), total volatile nitrogenous bases (TVB-N), pH, microbiological condition (pathogenic bacteria and aerobic psychrotrophic bacteria), and sensory attributes (color, odor, flavor, texture and overall acceptability) were evaluated for up to 40 days. The addition of MF to sausages increased TBARS values and decreases TVB-N, L*, a* and b* values. Acceptability of color attribute decreased with increasing MF; best flavor, texture and overall acceptability scores were registered for sausages containing 40 and 60% MF; best odor was registered for 100% MF. Pathogenic microorganisms were not detected, but decrease in pH and proliferation of aerobic psychrotrophic bacteria which, however, did not compromise sensory evaluation of sausages were registered throughout storage. Sausages prepared with MF from tilapia filleting waste have a shelf-life of 40 days when stored at 0±0.3ºC, and the maximum recommended MF inclusion to maintain good sensory quality is 60%.

Sensory evaluation of black instant coffee beverage with some volatile compounds present in aromatic oil from roasted coffee

The oil obtained from Brazilian roasted coffee by supercritical CO2 extraction shows considerable aromatic properties, mainly composed by five aromatic compounds, 2-methylpyrazine; 2-furfurylalcohol, 2,5-dimethylpyrazine; γ-butyrolactone and 2-furfurylacetate. Sensory analyses were used to verify the influence of a mixture of these important classes of aromatic coffee compounds (pyrazines, furans and lactones) and of the roasted coffee aromatic oil on the coffee aroma and flavour of black instant freeze and spray-dried coffee beverages. In the acceptance evaluation of the aroma, the samples prepared with freeze-dried instant coffee without the mixture of volatile compounds (sample 4) were not significantly different from the freeze-dried instant coffee in which the aromatic coffee oil was added (sample 5) and from the sample prepared with freeze-dried coffee in which the mixture of the five volatile was added (sample 3), coincidentally from the same drying process. Therefore, sample (3) did not differ from samples prepared with spray dried instant coffee without (sample 1) and to which (sample 2) the mixture of volatile was added. Therefore, with respect to this attribute, the addition of this mixture did not interfere in this drink acceptance. Taking into consideration the flavor, samples prepared with freeze-dried instant coffee in which the aromatic coffee oil was added (5) and the samples with (3) and without (4) the mixture of the five volatile was added did not differ significantly, however sample (4) did not differ from samples (1) and (2). Regarding this attribute, the addition of the aromatic oil of roasted coffee or a mixture of volatile in samples of freeze-dried instant coffee had a better acceptance than those dried by spray dryer (1) and (2). Thus, the enrichment of drinks with the aromatic oil of roasted coffee, or even with the mixture of the five components did not influence the consumer acceptance with respect to the aroma, but exerts influence with respect to flavour.

Efeitos de dietas com níveis crescentes de milho no metabolismo ruminal de energia e proteína em bubalinos

Avaliaram-se os efeitos de dietas com níveis crescentes de milho em grão moído (0, 22, 37 e 49% na MS) em substituição ao feno de coast-cross mantendo-se diferentes relações proteína:carboidratos não-fibrosos (PB:CNF = 1,01; 0,39; 0,33 e 0,27) sobre o metabolismo ruminal de búfalos. Utilizaram-se quatro búfalos fistulados no rúmen, mantidos em delineamento quadrado latino 4 × 4, para a coleta de amostras do líquido ruminal, colhidas em cada período experimental (de 28 dias) nos tempos 0, 2, 4 e 8 horas após a alimentação. Em geral, os bubalinos apresentaram boa capacidade tamponante no rúmen, com pH médio alto (6,70) e aumento da ingestão de milho em grão moído. O acréscimo nos níveis de milho na dieta promoveu aumento da produção de ácido butírico. Somente a dieta com 49% de milho promoveu melhor fermentação ruminal, com menor propoção de ácidos acético:propiônico. A relação PB:CNF de 1,01 indica deficiência de energia da dieta disponível para microrganismos no rúmen ao longo do dia, enquanto dietas com PB:CNF entre 0,39 e 0,27 promovem fermentações ruminais semelhantes, o que indica sincronismo na utilização de nitrogênio e energia pelos microrganismos no rúmen nessas condições.

Efeitos de dietas contendo Leucaena leucocephala e Saccharomyces cerevisiae sobre a fermentação ruminal e a emissão de gás metano em bovinos

Este trabalho foi realizado com o objetivo de avaliar os efeitos do uso de leucena e levedura em dietas para bovinos sobre o metabolismo ruminal, incluindo o pH e as produções de ácido graxos voláteis (AGV), amônia e gás metano. Quatro bovinos machos com 800 kg e fistulados no rúmen foram mantidos em quadrado latino 4 × 4, em arranjo fatorial 2 × 2, composto de dois níveis de leucena (20 e 50% MS) e feno de capim coast-cross na presença ou ausência de levedura. Não houve influência das dietas nos valores médios de pH (média 6,82) e nas concentrações de amônia no rúmen, que variaram de 18 a 21 mg/100 mL. Houve interação entre níveis de leucena e levedura na concentração total de AGV. As dietas não diferiram quanto à concentração de ácido acético, mas os animais alimentados com a dieta com 50% de leucena e contendo levedura apresentaram maiores concentrações médias de ácido propiônico (média 19,14 mM). A emissão de metano reduziu em12,3% em relação à mesma dieta sem levedura e em 17,2% quando os animais foram alimentados com 20% de leucena com levedura. Verificou-se efeito associativo de leucena, quando fornecida em alto nível na dieta (50% MS), e levedura na redução da emissão de metano e na melhoria no padrão de fermentação no rúmen, o que pode reduzir as perdas de energia e melhorar eficiência energética do animal.

Effects of dietary energy and nitrogen supplements on rumen fermentation and protozoa population in buffalo and zebu cattle

The effects were assessed of two energy sources in concentrate (ground grain corn vs. citrus pulp) and two nitrogen sources (soybean meal vs. urea) on rumen metabolism in four buffaloes and four zebu cattle (Nellore) with rumen cannula and fed in a 4 × 4 Latin square design with feeds containing 60% sugar cane. Energy supplements had no effect on the rumen ammonia concentration in cattle, but ground grain corn promoted higher ammonia level than citrus pulp in buffalo. Urea produced higher ammonia level than soybean meal in both animal species. On average, the buffaloes maintained a lower rumen ammonia concentration (11.7 mg/dL) than the cattle (14.5 mg/dL). Buffaloes had lower production of acetic acid than cattle (58.7 vs. 61.6 mol/100 mol) and higher of propionic acid (27.4 vs. 23.6 mol/100 mol). There was no difference in the butyric acid production between the buffaloes (13.6 mol/100 mol) and cattle (14.8 mol/100 mol) and neither in the total volatile fatty acids concentration (82.5 vs. 83.6 mM, respectively). The energy or nitrogen sources had no effect on rumen protozoa count in either animal species. The zebu cattle had higher rumen protozoa population (8.8 × 10(5)/mL) than the buffaloes (6.1 × 10(5)/mL). The rumen protozoa population differed between the animal species, except for Dasytricha and Charonina. The buffaloes had a lower Entodinium population than the cattle (61.0 vs 84.9%, respectively) and a greater percentage of species belonging to the Diplodiniinae subfamily than the cattle (28.6 vs. 1.4%, respectively). In cattle, ground corn is a better energy source than citrus pulp for use by Entodinium and Diplodiniinae. In the buffaloes, the Entodinium are favored by urea and Diplodiniinae species by soybean meal.