Tobacco policies in the European Union: a need for state and continental harmonisation?
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European Union↗
Biomedical subjects
Roberto Rodríguez
Publications and source records attributed to Roberto Rodríguez.
A strategy for blood vessels segmentation based on the threshold which combines statistical and scale space filter. Application to the study of angiogenesis.
This paper presents a strategy for segmenting blood vessels based on the threshold, which combines statistics and scale space filter. By incorporating statistical information, the strategy is capable of reducing over-segmentation. We propose a two-stage strategy which involves: (1) optimal selection of window size and (2) optimal selection of scale. We compared our strategy to two commonly used thresholding techniques. Experimental results showed that our method is much more robust and accurate. Our strategy suggested a modification to Otsu's method. In this application the important information to be extracted from images is only the number of blood vessels present in the images. The proposed segmentation technique is tested on manual segmentation, where segmentation errors less than 3% were observed. The work presented in this paper is a part of a global image analysis process. Therefore, these images will be subject to a further morphometrical analysis in order to diagnose and predict automatically malign tumors.
Algorithms↗
Liquid chromatographic method for quantifying polyphenols in ciders by direct injection.
An analytical method for the quantitative determination of the principal phenolic compounds (benzoic acids, hydroxycinnamic acids, 3-phenylpropionic acids, flavanols, procyanidins, dihydrochalcones, quercetin glycosides) in ciders, which successfully employs a RP-HPLC and photodiode-array detection system without prior treatment of the sample, is described. Parameters usually examined in the method validation were evaluated. Good linearity was obtained with correlation coefficients exceeding 0.999 and the detection limits ranged from 0.07 mg/L (p-hydroxybenzoic acid) to 2 mg/L (hydrocaffeic acid). Recoveries ranging between 90 and 104% and the reproducibility of the method was always < 8% (RSD). The method was applied to a set of commercial samples and the results obtained may be helpful to establish a phenolic profile in Asturian cider.
Beverages↗
Simple and inexpensive method for the reliable determination of additions of soybean proteins in heat-processed meat products: an alternative to the AOAC official method.
Despite the existence of an AOAC official method based on an enzyme-linked immunosorbent assay (ELISA) for the determination of additions of soybean proteins in meat products, its use for quantitative assessment is limited. Accordingly, a simple and inexpensive method has been developed and validated in this work. The method involves defatting the meat samples with acetone, solubilization of soybean proteins in a 30 mM Tris-HCl buffer (pH 8) containing 0.5% (v/v) 2-mercaptoethanol, and the identification of two peaks from soybean proteins in the chromatogram obtained by perfusion reversed-phase chromatography and UV detection. Determination of soybean proteins by the proposed method did not suffer from matrix interferences, with a good linear correlation up to a concentration of 12.50 mg/mL soybean proteins being observed. The proposed method was proven to be specific, precise, accurate, robust, and sensitive, making possible the detection and the quantitation of additions of 0.07% (w/w) and 0.25% (w/w), respectively, of soybean proteins in meat products (related to 1 g of initial product). The method has been applied to the determination of the soybean protein content in commercial heat-processed meat products, obtaining results that were statistically similar to those obtained by the official ELISA method but with a higher reliability and simplicity and a lower cost and analysis time.
Animals↗
A new strategy to obtain robust markers for blood vessels segmentation by using the watersheds method.
The watersheds method is a powerful segmentation tool developed in mathematical morphology. In order to prevent its over-segmentation, in this paper, we present a new strategy to obtain robust markers for segmentation of blood vessels from malignant tumors. For this purpose, we introduced a new algorithm. We propose a two-stage segmentation strategy which involves: (1) extracting an approximate region containing the blood vessel and part of the background near the blood vessel, and (2) segmenting the blood vessel from the background within this region. The approach effectively reduces the influence of peripheral background intensities on the extraction of a blood vessel region. In this application the important information to be extracted from images is only the number of blood vessels present in the images. The proposed strategy was tested on manual segmentation, where segmentation errors less than 10% for false positives and 0% for false negatives are observed. It is demonstrated by extensive experimentation, by using real images, that the proposed strategy was suitable for our application in the environment of a personal computer.
Algorithms↗
Statistical analyses: possible reasons for unreliability of source tracking efforts.
Analyses for the presence of indicator organisms provide information on the microbiological quality of water. Indicator organisms recommended by the United States Environmental Protection Agency for monitoring the microbiological quality of water include Escherichia coli, a thermotolerant coliform found in the feces of warm-blooded animals. These bacteria can also be isolated from environmental sources such as the recreational and pristine waters of tropical rain forests in the absence of fecal contamination. In the present study, E. coli isolates were compared to E. coli K12 (ATCC 29425) by restriction fragment length polymorphism using pulsed-field gel electrophoresis. Theoretically, genomic DNA patterns generated by PFGE are highly specific for the different isolates of an organism and can be used to identify variability between environmental and fecal isolates. Our results indicate a different band pattern for almost every one of the E. coli isolates analyzed. Cluster analysis did not show any relations between isolates and their source of origin. Only the discriminant function analysis grouped the samples with the source of origin. The discrepancy observed between the cluster analysis and discriminant function analysis relies on their mathematical basis. Our validation analyses indicate the presence of an artifact (i.e., grouping of environmental versus fecal samples as a product of the statistical analyses used and not as a result of separation in terms of source of origin) in the classification results; therefore, the large genetic heterogeneity observed in these E. coli populations makes the grouping of isolates by source rather difficult, if not impossible.
Animals↗
A Pinus radiata AAA-ATPase, the expression of which increases with tree ageing.
Age-dependent changes in gene expression profiles were studied in vegetative Pinus radiata buds by means of differential display. Among several candidate cDNAs, a 327 bp fragment that shows high homology with an Arabidopsis thaliana 20S proteasome ATPase designated RPT5a was found. Northern hybridization confirmed that the accumulation of this transcript increases with tree ageing, suggesting a possible role of this AAA-ATPase gene in development-related specific proteolysis.
Adenosine Triphosphatases↗
Changes in polyamine concentration associated with aging in Pinus radiata and Prunus persica.
Endogenous polyamine concentrations in apical buds of peach (Prunus persica (L.) Batsch cv. 'Hakuho') and monterey pine (Pinus radiata D. Don) seedlings, saplings and mature trees were analyzed by high performance liquid chromatography coupled with fluorescence detection to establish physiological correspondences and disparities between the species. Although there were many differences in polyamine metabolism between peach and monterey pine, several similarities were found. Specifically, in both species, the ratio between concentrations of free polyamines and low molecular-weight polyamine conjugates was greater than and less than unity in juvenile and adult plants, respectively. Free putrescine concentration decreased with age in both species.
Biogenic Polyamines↗
Reinvigoration of Pinus radiata is associated with partial recovery of juvenile-like polyamine concentrations.
Polyamine concentrations in consecutive radiata pine (Pinus radiata D. Don) grafts of 30-year-old trees on 1-year-old seedling rootstocks were analyzed by high performance liquid chromatography coupled with fluorescence detection to determine whether reinvigoration is associated with the recovery of polyamine concentrations typical of those in juvenile tissues. Reinvigoration of radiata pine was correlated with the attainment of some, but not all, polyamines characteristic of juvenile trees. In response to reinvigoration, free putrescine, the ratio of free polyamines to low molecular weight polyamine conjugates, and the relative content of putrescine versus spermidine plus spermine increased to values approaching those characteristic of juvenile tissue. In contrast, there was no noticeable change in the concentrations of low molecular weight polyamine conjugates during reinvigoration even though these conjugates increased greatly during tree maturation. We conclude that certain polyamines defined as reinvigoration markers can be used in forestry upgrading programs to assess the morphogenic ability of reinvigorated trees.
Biogenic Polyamines↗
Phase-change related epigenetic and physiological changes in Pinus radiata D. Don.
DNA methylation and polyamine levels were analysed before and after Pinus radiata D. Don. phase change in order to identify possible molecular and physiological phase markers. Juvenile individuals (without reproductive ability) were characterised by a degree of DNA methylation of 30-35% and a ratio of free polyamines to perchloric acid-soluble polyamine conjugates greater than 1, while mature trees (with reproductive ability) had 60% 5-methylcytosine and a ratio of free polyamines to perchloric acid-soluble polyamine conjugates of less than 1. Results obtained with trees that attained reproductive capacity during the experimental period confirmed that changes in the degree of DNA methylation and polyamine concentrations found among juvenile and mature states come about immediately after the phase change. We suggest that both indicators may be associated with the loss of morphogenic ability during ageing, particularly after phase change, through a number of molecular interactions, which are subsequently discussed.
DNA Methylation↗
High-performance capillary electrophoretic method for the quantification of 5-methyl 2'-deoxycytidine in genomic DNA: application to plant, animal and human cancer tissues.
A new approach to the evaluation of the relative degree of genomic DNA methylation through the quantification of 2'-deoxynucleosides is proposed. Detection and quantification of 5-methyl 2'-deoxycytidine in genomic DNA has been performed using micellar high-performance capillary electrophoresis (HPCE) with UV-Vis detection. This approach has been demonstrated to be more sensitive and specific than other HPCE methods for the quantification of DNA methylation degree and also to be faster than other HPLC-based methods. The detection and quantification of nucleosides through enzymatic hydrolyses notably increases the specificity of the technique and allows its exploitation in the analysis of poorly purified and/or concentrated DNA samples such as those obtained from meristematic plant regions and paraffin-embedded tissues.
Animals↗
Genomic DNA methylation-demethylation during aging and reinvigoration of Pinus radiata.
In animals, DNA methylation is related to gene silencing during ontogenic development. Little is known about DNA methylation in plants, although occasional changes in the DNA methylation state of specific gene promoters have been reported in angiosperms during some developmental processes. We found large differences in the extent of DNA methylation between meristematic areas of juvenile and mature Pinus radiata D. Don. trees, whereas differences in the extent of DNA methylation between differentiated tissues of juvenile and mature trees were small. In meristematic areas, there was a gradual decrease in extent of DNA methylation as the degree of reinvigoration increased. The observed changes in extent of DNA methylation during aging and reinvigoration indicate that reinvigoration could be a consequence of epigenetic modifications opposite in direction to those that occur during aging.
DNA Methylation↗
[Drugs in the European Union: the health-market complex].
OBJECTIVES: To characterize the peculiar economic nature of the pharmaceutical market in the EU, to study potential groupings of countries based on several pharmaceutical variables, to analyze some recent regulations designed to create the single market, and to present some thoughts on the decision making process in public health from the perspective of current public health budgets. METHOD: We performed an economic analysis of health and pharmaceutical macrovariables, cluster analysis, review of EU pharmaceutical and industrial regulations and review of pharmaceutical budgeting legislation in the member states. RESULTS: The pharmaceutical market of the EU was characterized and EU countries were classified into two principal groups according to 5 selected variables. EU regulations tend to promote R + D and drug production and thus the EU industrial sector is backed up. National regulations differ in terms of pricing and drugs reimbursement. CONCLUSIONS: The creation of a single market for drugs in the EU should take this regulatory diversity into account and seek equilibrium between economic factors and public health. This single market may be a dangerous strategy if it becomes a general dogma and even more so if deadlines are fixed and short.
Cluster Analysis↗
[Compendium of the first 100 years of scientific articles, writings, documents, editorials, and historical facts about medicine in the light of the times of the Boletín Científico de la Asociación Médica de Puerto Rico].
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Health Services↗