978 resultados para degree of polymerization (DP)
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Numerous health benefits have been attributed to cocoa and its derived products in the last decade including antioxidant, anti-platelet and positive effects on lipid metabolism and vascular function. Inflammation plays a key role in the initiation and progression of atherosclerosis. However, cocoa feeding trials focused on inflammation are still rare and the results yielded are controversial. Health effects derived from cocoa consumption have been partly attributed to its polyphenol content, in particular of flavanols. Bioavailability is a key issue for cocoa polyphenols in order to be able to exert their biological activities. In the case of flavanols, bioavailability is strongly influenced by several factors, such as their degree of polymerization and the food matrix in which the polyphenols are delivered. Furthermore, gut has become an active site for the metabolism of procyanidins (oligomeric and polymeric flavanols). Estimation of polyphenol consumption or exposure is also a very challenging task in Food and Nutrition Science in order to correlate the intake of phytochemicals with in vivo health effects. In the area of nutrition, modern analytical techniques based on mass spectrometry are leading to considerable advances in targeted metabolite analysis and particularly in Metabolomics or global metabolite analysis. In this chapter we have summarized the most relevant results of our recent research on the bioavailability of cocoa polyphenols in humans and the effect of the matrix in which cocoa polyphenols are delivered considering both targeted analysis and a metabolomic approach. Furthermore, we have also summarized the effect of long-term consumption of cocoa powder in patients at high risk of cardiovascular disease (CVD) on the inflammatory biomarkers of atherosclerosis.
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CONTEXT: Compensatory increases in FGF23 with increasing phosphate intake may adversely impact health. However, population and clinical studies examining the link between phosphate intake and FGF23 levels have focused mainly on populations living in highly industrialized societies in which phosphate exposure may be homogenous. OBJECTIVE: Contrast dietary phosphate intake, urinary measures of phosphate excretion and FGF23 levels across populations that differ by level of industrialization. DESIGN: Cross-sectional analysis of three populations Setting: Maywood, IL, U.S., Mah|fe Island, Seychelles, and Kumasi, Ghana Participants: Adults with African ancestry aged 25-45 years Main Outcome: Fibroblast growth factor 23 (FGF23) levels Results: The mean age was 35.1 (6.3) years and 47.9% were male. Mean phosphate intake and fractional excretion of phosphate were significantly higher in the U.S. vs. Ghana while no significant difference in phosphate intake or fractional excretion of phosphate was noted between U.S. and Seychelles for men or women. Overall, median FGF23 values were 57.41 RU/ml (IQR 43.42, 75.09) in U.S., 42.49 RU/ml (IQR 33.06, 55.39) in Seychelles and 33.32 RU/ml (IQR 24.83, 47.36) in Ghana. In the pooled sample, FGF23 levels were significantly and positively correlated with dietary phosphate intake (r=0.11; P < 0.001), and the fractional excretion of phosphate (r=0.13; P < 0.001) but not with plasma phosphate levels (-0.001; P = 0.8). Dietary phosphate intake was significantly and positively associated with the fractional excretion of phosphate (r=0.23; P < 0.001). CONCLUSION: The distribution of FGF23 levels in a given population may be influenced by the level of industrialization, likely due to differences in access to foods preserved with phosphate additives.
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A multicompartment compliance aid (MCA) is a blister-type repackaging system that aims to facilitate drug administration and thereby increase patient adherence. One of the characteristics of the MCA that should be taken into account is the moisture permeability, since this atmospheric condition is one of the most important factors that can modify the stability of medicines. In the current paper we report the moisture permeability tests performed on a MCA according to the US Pharmacopeia. This information on the suitability of the device will help pharmacists implement a high-quality professional service.
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Aim: To investigate and understand patient's satisfaction with nursing care in the intensive care unit to identify the dimensions of the concept of"satisfaction" from the patient's point of view. To design and validate a questionnaire that measures satisfaction levels in critical patients. Background: There are many instruments capable of measuring satisfaction with nursing care; however, they do not address the reality for critical patients nor are they applicable in our context. Design: A dual approach study comprising: a qualitative phase employing Grounded Theory and a quantitative and descriptive phase to prepare and validate the questionnaire. Methods: Data collection in the qualitative phase will consist of: in-depth interview after theoretical sampling, on-site diary and expert discussion group. The sample size will depend on the expected theoretical saturation n = 27-36. Analysis will be based on Grounded Theory. For the quantitative phase, the sampling will be based on convenience (n = 200). A questionnaire will be designed on the basis of qualitative data. Descriptive and inferential statistics will be used. The validation will be developed on the basis of the validity of the content, the criteria of the construct and reliability of the instrument by the Cronbach's alpha and test-retest approach. Approval date for this protocol was November 2010. Discussion: Self-perceptions, beliefs, experiences, demographic, socio-cultural epistemological and political factors are determinants for satisfaction, and these should be taken into account when compiling a questionnaire on satisfaction with nursing care among critical patients.
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Locomotor problems prevent the bird to move freely, jeopardizing the welfare and productivity, besides generating injuries on the legs of chickens. The objective of this study was to evaluate the influence of age, use of vitamin D, the asymmetry of limbs and gait score, the degree of leg injuries in broilers, using data mining. The analysis was performed on a data set obtained from a field experiment in which it was used two groups of birds with 30 birds each, a control group and one treated with vitamin D. It was evaluated the gait score, the asymmetry between the right and left toes, and the degree of leg injuries. The Weka ® software was used in data mining. In particular, C4.5 algorithm (also known as J48 in Weka environment) was used for the generation of a decision tree. The results showed that age is the factor that most influences the degree of leg injuries and that the data from assessments of gait score were not reliable to estimate leg weakness in broilers.
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Purpose To evaluate the compliance and degree of satisfaction of nulligravida (has not given birth) and parous (had already given birth) women who are using intrauterine devices (IUDs). Methods A cross-sectional cohort study was conducted comparing nulligravida and parous women who had had an IUD inserted between July 2009 and November 2011. A total of 84 nulligravida women and 73 parous women were included. Interviews were conducted with women who agreed to participate through telephone contact. Statistical analysis was performed with Student s t-test and Mann-Whitney test for numeric variables; Pearson s chi-square test to test associations; and, whenever pertinent, Fisher s exact test for categorical variables. A survival curve was constructed to estimate the likelihood of each woman continuing the use of the IUD. A significance level of 5% was established. Results When compared with parous women, nulligravida women had a higher education level (median: 12 vs. 10 years). No statistically significant differences were found between the nulligravida and parous women with respect to information on the use of the IUD, prior use of other contraceptive methods, the reason for having chosen the IUD as the current contraceptive method, reasons for discontinuing the use and adverse effects, compliance, and degree of satisfaction. The two groups did not show any difference in terms of continued use of the IUD (p = 0.4). Conclusion There was no difference in compliance or the degree of satisfaction or continued use of IUDs between nulligravida and parous women, suggesting that IUD use may be recommended for women who have never been pregnant.
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High dimensional dynamical systems has intricate behavior either on temporal or on spatial evolution properties. Nevertheless, most of the work on chaotic dynamics has been concentrated on temporal behavior of low-dimensional systems. This contribution is concerned with the chaotic response of a two-degree of freedom Duffing oscillator. Since the equations of motion are associated with a five-dimensional system, the analysis is performed by considering two Duffing oscillators, both with single-degree of freedom, coupled by a spring-dashpot system. With this assumption, it is possible to analyze the transmissibility of motion between the two oscillators.
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This thesis describes work related to the in-depth characterization of the phenolic compounds of silver birch (Betula pendula) inner bark. Phenolic compounds are the most ubiquitous class of plant secondary compounds. The unifying feature of this structurally diverse group is an aromatic ring containing at least one hydroxyl group. Due to the structural diversity, phenolics have various roles in the plant defense against biotic and abiotic stresses. In addition, they can confer several health-promoting properties to humans. Furthermore, the structural diversity of this class of compounds causes challenges for their analysis. The study species in the present work, silver birch, is economically the most important hard wood species in northern Europe. Its inner bark contains a high level of phenolic compounds and it has shown one of the strongest antioxidant activities among 92 Finnish plant materials. The literature review surveys the diversity and organ specific distribution of phenolic compounds in silver birch as well as the proposed ecological functions of phenolic compounds in nature. In addition, the basis for the characterization of phenolics by mass spectrometry (MS), nuclear magnetic resonance spectroscopy (NMR), and circular dichroism spectroscopy (CD) are reviewed. The objective of the experimental work was to extract, purify, characterize, and quantify the inner bark phenolic compounds. Overall 36 compounds were characterized by MS and ultraviolet spectroscopy (UV). 24 compounds were isolated and their structures confirmed by NMR and CD spectroscopy. Five novel natural compounds were identified. Special emphasis was placed on the establishment of a method for the characterization of proanthocyanidins (PAs). Hydrophilic interaction liquid chromatography (HILIC) was utilized because of its high resolution power and predictable elution order of oligomeric and polymeric PAs according to an increasing degree of polymerization. The combination of HILIC and high-resolution MS detection allowed the identification of procyanidin (PC) polymers up to the degree of polymerization of 22. In addition, a series of oligomeric and polymeric PC monoxylosides were observed for the first time in nature. Season and genotype influenced the quantities of the main inner bark phenolics, yet qualitative differences were not observed. However, manual wounding of the inner bark induced the production of ellagitannins (ETs) in the wounded tissues, i.e. callus. Since ETs were not detected in the intact inner bark, this finding may reflect the capacity of silver birch to exploit ellagitannins in its defense.
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The underground organs of Vernonia herbacea (Vell.) Rusby, known as rhizophores, acumulate 80% of their dry mass as fructans of the inulin type. In view of the growing industrial use of fructans as dietetic and general food products, and of their medical application, the present investigation aimed at evaluating the effect of mineral fertilization and period of cultivation on the production of these carbohydrates in field trials. Plants used in the experiments were obtained by vegetative propagation from rhizophores collected from plants growing in natural areas of the cerrado, and cultivated for two years. Fertilization consisted of N:P2O5:K2O (80:200:150 kg.ha-1) plus 80 kg.ha-1 nitrogen as dressing. Soil fertilization did not stimulate biomass or inulin production, but in the second year of cultivation a dramatic gain in biomass and inulin was detected in both treated and control plants. Inulin production varied from 113 to 674 kg.ha-1 which corresponds to 43% of the rhizophore dry mass. The composition of fructans was not altered by fertilization, although treated plants had a higher proportion of sucrose and fructans with degree of polymerization 3-8 in the second year of cultivation. The results identify this species as a fructan source similar to other commercial crops and recommend further agronomic studies, aimed at increasing the production of this polysaccharide.
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Recent reports showing a decrease in sperm count in men have brought new concerns about male infertility. Animal models have been widely used to provide some relevant information about the human male gamete, and extrapolations are made to men and to the clinical context. The present study assesses one of the methods used for separation of germ cells of the adult rat testis, namely centrifugal elutriation followed by density gradients (Percoll®). This method was chosen since it presents the best results for cell purity in separating germ cells from the rat testis. A comparison between continuous and discontinuous Percoll® gradients was performed in order to identify the best type of gradient to separate the cells. Maximal cell purity was obtained for spermatocytes (81 ± 8.2%, mean ± SEM) and spermatids (84 ± 2.6%) using centrifugal elutriation followed by continuous Percoll® gradients. A significant difference in purity was observed between elongating spermatids harvested from continuous Percoll® gradients and from discontinuous gradients. Molecular analysis was used to assess cell contamination by employing specific probes, namely transition protein 2 (TP2), mitochondrial cytochrome C oxidase II (COX II), and sulfated glycoprotein 1 (SGP1). Molecular analysis of the samples demonstrated that morphological criteria are efficient in characterizing the main composition of the cell suspension, but are not reliable for identifying minimal contamination from other cells. Reliable cell purity data should be established using molecular analysis
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Hypolactasia associated with severe iron-deficiency anemia has been reported in several studies. The objective of the present study was to determine whether hypolactasia is associated with the degree and duration of iron-deficiency anemia. Newly weaned male Wistar rats were divided into a control group receiving a diet supplemented with iron (C) and an experimental group (E) receiving a diet not supplemented with iron (iron-deficiency diet). The animals were studied on the 3rd, 5th, 7th, 14th, 21st, 28th and 35th days of the experiment, when overall and iron nutritional status and disaccharidase activity in the small intestine were determined by the Dahlqvist method. A reduction in weight occurred in the anemic animals starting on the 5th day of the study. Anemia was present in the experimental animals, with a progressive worsening up to the 14th day (hemoglobin: C = 13.27 and E = 5.37) and stabilizing thereafter. Saccharase and maltase activities did not differ significantly between groups, whereas lactase showed a significant reduction in total (TA) and specific activity (SA) in the anemic animals starting on the 21st day of the study. Median lactase TA for the C and E groups was 2.27 and 1.25 U on the 21st day, 2.87 and 1.88 U on the 28th day, and 4.20 and 1.59 U on the 35th day, respectively. Median lactase SA was 0.31 and 0.20 U/g wet weight on the 21st day, 0.39 and 0.24 U/g wet weight on the 28th day, and 0.42 and 0.23 U/g wet weight on the 35th day, respectively. These findings suggest a relationship between the enzymatic alterations observed and both the degree and duration of the anemic process. Analysis of other studies on intestinal disaccharidases in anemia suggests that the mechanism of these changes may be functional, i.e., that the enterocytes may suffer a reduction in their ability to synthesize these enzymes.
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The intake of carotenoids is associated with antioxidant properties and some of these substances have activity of pro-vitamin A. This study aimed to estimate the intake of carotenoids (average values) by the Brazilian population focusing on beneficiaries of the 'Bolsa Família' Program and identify the dietary sources, according to the purpose and degree of processing and the inclusion of food additives. The database used is the personal food consumption module of the Household Budget Survey of 2008-2009, conducted by the Brazilian Institute of Geography and Statistics. The content of carotenoids in foods was obtained primarily from a National data source. Food products were classified into three categories: 1) fresh and minimally processed foods; 2) processed foods (containing food additives, except for flavoring and coloring agents); and 3) highly processed foods (containing flavoring and coloring agents). Insufficient intakes were identified for the conditional cash transfer program beneficiaries (3,547.1 µg). Fresh and minimally processed foods supplied between 48.6% (for girls) and 65.7% (for male adults) of pro-vitamin carotenoids. Processed foods were sources of between 55.5% and 57.0% of lutein + zeaxanthin for elderly and between 58.0% and 67.8% of lycopene for adults. Highly processed foods contributed to less than 5.0% of total carotenoids.
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Abstract The objective of this work was to evaluate the antioxidant activity of protein hydrolysates obtained by the enzymatic hydrolysis of okara using an endopeptidase (Alcalase) and exopeptidase (Flavourzyme). The reaction was monitored by the pH-stat procedure in which five aliquots were collected during the hydrolysis by each enzyme, corresponding to different degrees of hydrolysis (DH). The antioxidant activities of the aliquots were evaluated by the ABTS, DPPH and FRAP methods. For the hydrolysates obtained using Alcalase, the antioxidant activities increased from: 68.6 to 99.5% (ABTS), 14.5 to 17.7% (DPPH) and 222.6 to 684.9 µM Trolox (FRAP), when the DH varied from 0 to 33.6%. With respect to Flavourzyme, the results were: 67.2 to 88.2% (ABTS), 9.5 to 18.5% (DPPH) and 168.0 to 360.3 µM Trolox (FRAP), when the DH increased up to 5.8%. The results showed that the protein hydrolysates had antioxidant capacities, which were influenced by the degree of hydrolysis and the type of enzyme.
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Collection : Publications of the University of Pennsylvania ; n° 6
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The purpose of this qualitative research study was to foster an understanding of the rehabilitation counselling practice offamilies of the brain-injured. Specifically, the study explores the perceptions of stakeholders in regards to the degree of satisfaction with the quality of service received. Questionnaires were administered, and semi-structured, openended interviews were conducted, with six participating families (n=8). Preliminary data were collected via two instruments: (i) the Family Participant Questionnaire, consisting of participants' sample characteristics, information pertaining to the history of the family, details of the injury, and information relating to the type, use, and need offamily services utilized; and (ii) the Community Integration Questionnaire, a measurement of the degree of social displacementllevel of community integration of the injured family member. Utilizing the procedural steps outlined by Colaizzi's (1978) method of protocol analysis, recommendations for a future program based on related and current family needs are discussed in detail. Substantiating and supporting information are offered to rehabilitation practitioners, educational planners, and policymakers alike, concerning the degree of satisfaction with rehabilitative service, and the means of improving upon the overall quality of health care to families of the brain-injured. Implications for clinical practice and research are also raised for discussion.