Guia de lípids i risc cardiovascular

Colesterol; Risc coronari; HipercolesterolèmiaCholesterol; Coronary risk; HypercholesterolemiaColesterol; Riesgo coronario; HipercolesterolemiaL’objectiu general d’aquesta guia és disposar d’unes recomanacions basades en l’evidència científica sobre el maneig dels lípids segons el risc cardiovascular (RCV). Aquesta guia engloba tot el procés assistencial i inclou els objectius comuns per tal d’augmentar la qualitat assistencial i disminuir la variabilitat assistencial en l’abordatge dels lípids i l’RCV

La Bioremediació

La biotecnologia de la bioremediació es basa a aprofitar les capacitats metabòliques dels microorganismes per degradar els contaminants químics presents en diferents matrius ambientals, majoritàriament sòls, incloent-hi les aigües subterrànies. Fins avui dia, la tipologia de contaminants amb la qual s'ha mostrat més eficaç són els hidrocarburs. En la majoria de casos es basa a estimular les poblacions microbianes presents a l'emplaçament mateix, atesa la seva adaptació a la presència dels contaminants. En altres ocasions s'afegeixen inòculs microbians obtinguts al laboratori amb les capacitats catabòliques adients. Abans de portar a terme una bioremediació s'han de conèixer les poblacions microbianes presents i els factors ambientals que les condicionen amb l'aplicació dels assaigs de tractabilitat. A diferència d'altres països europeus, el nostre país està tot just començant, a causa del retard en l'aparició de la legislació pertinent. No obstant això, atès que les estimacions efectuades a Catalunya xifren en unes trenta mil les activitats potencialment contaminants del sòl, l'aplicació de les normatives aparegudes recentment comportarà un impuls per a aquesta matèria. En el cas concret de Catalunya es descriuen tres casos desenvolupats a escala pilot. Finalment, s'apunten diferents aspectes necessitats d'investigació que haurien de permetre ampliar la tipologia de contaminants susceptibles de ser tractats i reduir el temps de procés.The biotechnology of the bioremediation is based on the metabolic capacities of the microorganisms to degrade the chemical pollutants in different environmental compartments, especially soil including underground waters. Until the present time, the type of pollutants more suitable to be treated by bioremediation are the hydrocarbons. In most of cases it is based on stimulating the microbial populations present in the location, given their high adaptation to the presence of the pollutants. In other cases microbial inócula, obtained in the laboratory with the appropriate metabolic capacities, are added. Before carrying out a bioremediation it is important to know the microbial populations present in the site and the environmental factors that they condition the biodegradation process by means of the application of feasibility assays. Contrary to other European countries, our country is in its beginnings due to the delay in the pertinent appearance of the normative ones. Nevertheless, keeping in mind that the estimates made in Catalonia calculate potentially in 30.000 the pollutants activities of the soil, the application of the normative recently appeared behaved an impulse in the matter. In the case of Catalonia, three scale pilot cases are described. Finally, different needy aspects of research are aimed that must allow to enlarge the typology of susceptible pollutants of being treated by bioremediation as well as reduce the time of the process

New metabolites in the degradation of fluorene by Arthrobacter sp. strain F101

8 pages, 3 figures, 1 table.-- PMID: 9055403 [PubMed].-- PMCID: PMC168377.Identification of new metabolites and demonstration of key enzyme activities support and extend the pathways previously reported for fluorene metabolism by Arthrobacter sp. strain F101. Washed-cell suspensions of strain F101 with fluorene accumulated 9-fluorenone, 4-hydroxy-9-fluorenone, 3-hydroxy-1-indanone, 1-indanone, 2-indanone, 3-(2-hydroxyphenyl) propionate, and a compound tentatively identified as a formyl indanone. Incubations with 2-indanone produced 3-isochromanone. The growth yield with fluorene as a sole source of carbon and energy corresponded to an assimilation of about 34% of fluorene carbon. About 7.4% was transformed into 9-fluorenol, 9-fluorenone, and 4-hydroxy-9-fluorenone. Crude extracts from fluorene-induced cells showed 3,4-dihydrocoumarin hydrolase and catechol 2,3-dioxygenase activities. These results and biodegradation experiments with the identified metabolites indicate that metabolism of fluorene by Arthrobacter sp. strain F101 proceeds through three independent pathways. Two productive routes are initiated by dioxygenation at positions 1,2 and 3,4, respectively. meta cleavage followed by an aldolase reaction and loss of C-1 yield the detected indanones. Subsequent biological Baeyer-Villiger reactions produce the aromatic lactones 3,4-dihydrocoumarin and 3-isochromanone. Enzymatic hydrolysis of the former gives 3-(2-hydroxyphenyl) propionate, which could be a substrate for a beta oxidation cycle, to give salicylate. Further oxidation of the latter via catechol and 2-hydroxymuconic semialdehyde connects with the central metabolism, allowing the utilization of all fluorene carbons. Identification of 4-hydroxy-9-fluorenone is consistent with an alternative pathway initiated by monooxygenation at C-9 to give 9-fluorenol and then 9-fluorenone. Although dioxygenation at 3,4 positions of the ketone apparently occurs, this reaction fails to furnish a subsequent productive oxidation of this compound.This research was funded by a grant from the National Plan for Research (AMB93-0693-C02-02) of the Spanish government. M.C. was in receipt of a doctoral fellowship from the Spanish Ministry of Education.Peer reviewe

Alcanivorax strain detected among the cultured bacterial community from sediments affected by the 'Prestige' oil spill

12 pages.Sediments sampled next to the Cíes Islands, a natural reserve of the National Park of Atlantic Islands in Ría de Vigo (Spain), 3 mo after the first tide of fuel from the ‘Prestige’ tanker arrived, were chemically and microbiologically characterized. The chemical analysis of the sediments, using oil fingerprinting techniques, showed the occurrence of fresh ‘Prestige’ fuel oil with a background of older hydrocarbon contamination. The cultured bacterial community of the contaminated sediments harbored a high population of total heterotrophs and alkane degraders and a small proportion of aromatic-degrading bacteria. Based on partial 16S ribosomal RNA gene sequence data, 37 different bacterial strains, isolated in diluted marine agar, were detected. Most of them were classified as members of the groups Gammaproteobacteria (59%) and Alphaproteobacteria (21%), although members of the Bacteroidetes (10%) and of Firmicutes (10%) were also found. Some of the different identified bacteria have previously been described as fuel oil–degrading species such as Alcanivorax, Shewanella, Vibrio, Pseudoalteromonas and Marinomonas. Seven independent isolates were able to grow with hexadecane. However, these 7 strains are grouped under the same phylotype, based on the 16S rRNA gene sequence, and were closely related to Alcanivorax borkumensis (Gammaproteobacteria). No aromatic-degrading activities were detected among the culturable bacteria. The presence of fresh fuel without a detected level of biodegradation suggests that Alcanivorax was an early colonizer after the ‘Prestige’ oil spill. To our knowledge, the isolation of Alcanivorax from environmental samples without the aid of an enrichment procedure has not been previously reported. Our results suggest the ability of Alcanivorax to compete and coexist with other heterotrophic marine bacteria in an oil polluted marine environment rich in the nutrients N and P.Peer reviewe

Bacterial Community Dynamics and Polycyclic Aromatic Hydrocarbon Degradation during Bioremediation of Heavily Creosote-Contaminated Soil

Bacterial community dynamics and biodegradation processes were examined in a highly creosote-contaminated soil undergoing a range of laboratory-based bioremediation treatments. The dynamics of the eubacterial community, the number of heterotrophs and polycyclic aromatic hydrocarbon (PAH) degraders, and the total petroleum hydrocarbon (TPH) and PAH concentrations were monitored during the bioremediation process. TPH and PAHs were significantly degraded in all treatments (72 to 79% and 83 to 87%, respectively), and the biodegradation values were higher when nutrients were not added, especially for benzo(a)anthracene and chrysene. The moisture content and aeration were determined to be the key factors associated with PAH bioremediation. Neither biosurfactant addition, bioaugmentation, nor ferric octate addition led to differences in PAH or TPH biodegradation compared to biodegradation with nutrient treatment. All treatments resulted in a high first-order degradation rate during the first 45 days, which was markedly reduced after 90 days. A sharp increase in the size of the heterotrophic and PAH-degrading microbial populations was observed, which coincided with the highest rates of TPH and PAH biodegradation. At the end of the incubation period, PAH degraders were more prevalent in samples to which nutrients had not been added. Denaturing gradient gel electrophoresis analysis and principal-component analysis confirmed that there was a remarkable shift in the composition of the bacterial community due to both the biodegradation process and the addition of nutrients. At early stages of biodegradation, the α-Proteobacteria group (genera Sphingomonas and Azospirillum) was the dominant group in all treatments. At later stages, the γ-Proteobacteria group (genus Xanthomonas), the α-Proteobacteria group (genus Sphingomonas), and the Cytophaga-Flexibacter-Bacteroides group (Bacteroidetes) were the dominant groups in the nonnutrient treatment, while the γ-Proteobacteria group (genus Xathomonas), the β-Proteobacteria group (genera Alcaligenes and Achromobacter), and the α-Proteobacteria group (genus Sphingomonas) were the dominant groups in the nutrient treatment. This study shows that specific bacterial phylotypes are associated both with different phases of PAH degradation and with nutrient addition in a preadapted PAH-contaminated soil. Our findings also suggest that there are complex interactions between bacterial species and medium conditions that influence the biodegradation capacity of the microbial communities involved in bioremediation processes

The Prestige oil spill: bacterial community dynamics during a field biostimulation assay

11 pages, 5 figures, 3 tables.-- PMID: 17943279 [PubMed].-- Printed version published Dec 2007.A further paper on the Prestige oil spill series available at: http://digital.csic.es/handle/10261/11538A field bioremediation assay using the oleophilic fertilizer S200 was carried out 12 months after the Prestige heavy fuel-oil spill on a beach on the Cantabrian coast (north Spain). This assay showed that S200-enhanced oil degradation, particularly of high-molecular-weight n-alkanes and alkylated PAHs, suggesting an increase in the microbial bioavailability of these compounds. The bacterial community structure was determined by cultivation-independent analysis of polymerase chain reaction-amplified 16S rDNA by denaturing gradient gel electrophoresis. Bacterial community was mainly composed of α-Proteobacteria (Rhodobacteriaceae and Sphingomonadaceae). Representatives of γ-Proteobacteria (Chromatiales, Moraxellaceae, and Halomonadaceae), Bacteroidetes (Flavobacteriaceae), and Actinobacteria group (Nocardiaceae and Corynebacteriaceae) were also found. The addition of the fertilizer led to the appearance of the bacterium Mesonia algae in the early stages, with a narrow range of growth substrates, which has been associated with the common alga Achrosiphonia sonderi. The presence of Mesonia algae may be attributable to the response of the microbial community to the addition of N and P rather than indicating a role in the biodegradation process. The Rhodococcus group appeared in both assay plots, especially at the end of the experiment. It was also found at another site on the Galician coast that had been affected by the same spill. This genus has been associated with the degradation of n-alkanes up to C36. Taking into account the high content of heavy alkanes in the Prestige fuel, these microorganisms could play a significant role in the degradation of such fuel. A similar bacterial community structure was observed at another site that showed a similar degree of fuel weathering.This study was financially supported by the Spanish Ministry of Science and Technology (VEM2003-20068-C05) and by Tank Recovery S.A. (Santander, Spain). Finally, N.J. acknowledges a PhD fellowship from the Spanish Ministry of Education and Science. The authors declare that the experiments discussed in this paper complied with current Spanish law.Peer reviewe

Comparative assessment of bioremediation approaches to highly recalcitrant PAH degradation in a real industrial polluted soil

High recalcitrant characteristics and low bioavailability rates due to aging processes can hinder high molecular weight polycyclic aromatic hydrocarbons (HMW-PAHs) bioremediation in real industrial polluted soils. With the aim of reducing the residual fraction of total petroleum hydrocarbons (TPH) and (HMW-PAHs) in creosote-contaminated soil remaining after a 180-d treatment in a pilot-scale biopile, either biostimulation (BS) of indigenous microbial populations with a lignocellulosic substrate (LS) or fungal bioaugmentation with two strains of white-rot fungi (WRF) (i.e., Trametes versicolor and Lentinus tigrinus) were comparatively tested. The impact of bivalent manganese ions and two mobilizing agents (MAs) (i.e., Soybean Oil and Brij 30) on the degradation performances of biostimulated and bioaugmented microcosms was also compared. The results reveal soil colonization by both WRF strains was clearly hampered by an active native soil microbiota. In fact, a proper enhancement of native microbiota by means of LS amendment promoted the highest biodegradation of HMW-PAHs, even of those with five aromatic rings after 60 days of treatment, but HMW-PAH-degrading bacteria were specifically inhibited when non-ionic surfactant Brij 30 was amended. Effects of bioaugmentation and other additives such as non-ionic surfactants on the degrading capability of autochthonous soil microbiota should be evaluated in polluted soils before scaling up the remediation process at field scale

Biodegradation of the Prestige fuel oil under simulated conditions

25 pages.-- Presented at VERTIMAR 2005. Symposium on Marine Accidental Oil Spills, july 13-16, 2005, Vigo (Pontevedra), Spain.Peer reviewe

Chemical analysis and bacterial diversity associated to marine sediments affected by the “Prestige” oil-spill

37 pages.-- Presented at VERTIMAR 2005. Symposium on Marine Accidental Oil Spills, july 13-16, 2005, Vigo (Pontevedra), Spain.Peer reviewe