RESUMEN
Three catch crop species, ryegrass, forage rape and black oat, were grown between successive rotations of maize to reduce nitrogen leaching due to maize fertilization with digested dairy manure. Catch crops showed a high nutrient uptake, but with a wide range, depending on the year and the specie. Ensiling was shown to be a feasible storing method increasing catch crop methane production per hectare between 14-36% compared with fresh catch crop. In semi-continuous co-digestion experiments, methane production was increased between 35-48%, in comparison with anaerobic digestion of dairy manure alone. Catch crops were shown to be a good co-substrate, being a sustainable option to prevent leaching of nutrients to the environment, thus closing the loops from production to utilization by optimal recycling measures.
Asunto(s)
Biocombustibles , Estiércol , Anaerobiosis , Digestión , Metano , Nutrientes , Zea maysRESUMEN
The presence of potentially toxic elements (PTEs) may hinder a more widespread application of biosolids in agriculture. At present, the European Directive 86/278/CEE limit the total concentrations of seven metals (Cu, Cr, Ni, Pb, Zn, Cd and Hg) in agricultural soils and in sewage sludges used as fertilizers but it has not taken into consideration the potential impacts of other emerging micropollutants that may be present in the biosolids as well as their mobility. The aim of this study was to evaluate the accumulation and mobility of 13 elements (including regulated metals and other inorganic species) in agricultural soils repeatedly amended with biosolids for 15 years. Firstly, three digestions programs using different acid mixtures were tested to evaluate the most accurate and efficient method for analysis of soil and sludge. Results demonstrated that sewage sludge application increased concentrations of Pb and Hg in soil, but values did not exceed the quality standard established by legislation. In addition, other elements (As, Co, Sb, Ag, Se and Mn) that at present are not regulated by the Spanish and European directives were identified in the sewage sludge, and significant differences were found between Ag content in soils amended with biosolids in comparison with control soils. This fact can be related to the increasing use of silver nanoparticles in consumer products due to their antibacterial properties. Results from the leaching tests show up that, in general, the mobility degree for both regulated and non-regulated elements in soils amended with biosolids was quite low (<10 %).
Asunto(s)
Fertilizantes , Aguas del Alcantarillado/análisis , Contaminantes del Suelo/análisis , Suelo , Agricultura , Fertilizantes/toxicidad , Metales Pesados/análisisRESUMEN
The behavioural responses of the haematophagous bug Triatoma infestans towards some previously identified components of its faeces: 4-methylquinazoline, 2,4- dimethylquinazoline and their mixtures were evaluated using a video tracking system. Fifth instar nymphs and females but not males were significantly attracted to polyethylene glycol formulations of 4-methyl + 2,4-dimethylquinazoline (50 microg each). Fifth instar nymphs were also attracted to 4-methylquinazoline alone (50 microg) but females were only attracted by the mixture of both methyl quinazolines (50 microg each). Syntheses of both methyl quinazolines were carried out starting from 2-aminoacetophenone by modifying the conditions of reported procedures.
Asunto(s)
Conducta Animal/efectos de los fármacos , Quinazolinas/farmacología , Triatoma/efectos de los fármacos , Animales , Bioensayo , Femenino , Masculino , Ninfa/efectos de los fármacos , Quinazolinas/químicaRESUMEN
The female sex pheromones of the Mediterranean processionary moths (Thaumetopoea sp.) are conjugated dienes or enynes of 16 carbon atoms with the unsaturations located at C11 and C13. To investigate the biochemical basis of this phenotypic variation, the biosynthetic pathway of T. processionea sex pheromone, a diene acetate, has been elucidated and compared to that reported for the enyne-producing species T. pityocampa. Mass labeling experiments showed that T. processionea sex pheromone is biosynthesized from palmitic acid, by subsequent (Z)-11 and (Z)-13 desaturations and final reduction and acetylation. The Pheromone Biosynthesis Activating Neuropeptide (PBAN) activates this biosynthetic pathway downstream of the dienoate intermediate. When either 11-hexadecynoic acid or (Z)-13-hexadecen-11-ynoic acid were administered to T. processionea, this species was able to produce the enyne sex pheromone of T. pityocampa upon PBAN stimulation. In contrast, T. pityocampa does not produce either 11-hexadecynyl acetate or (Z,Z)-11,13-hexadecadienyl acetate, despite having the corresponding precursors in the pheromone gland. However, both acetates are detected after administration of the corresponding alcohols. These overall results suggest that the absence of delta(11) acetylenase and the existence of an enynoate specific reductase in the diene and enyne-producing Thaumetopeae, respectively, account for the different sex pheromones produced by the two groups.
Asunto(s)
Variación Genética , Mariposas Nocturnas/fisiología , Atractivos Sexuales/genética , Animales , Femenino , Masculino , Mariposas Nocturnas/genética , Fenotipo , Pupa , Especificidad de la EspecieRESUMEN
In order to investigate the potential utility of thiafatty acids as tracers for biosynthetic studies of moth sex pheromones, a series of thiatetradecanoic acids, namely 8-, 9-, 10-, 11-, 12- and 13-thiatetradecanoic, were prepared and their metabolism was investigated in pheromone glands of Spodoptera littoralis. Analysis by gas chromatography coupled to mass spectrometry of extracts from pheromone glands treated with the above acids showed that only 8-thiatetradecanoic acid and 13-thiatetradecanoic acid were metabolized by desaturation and were incorporated into the sex pheromone biosynthetic pathway. 13-Thiatetradecanoic acid was converted into (E)- and (Z)-13-thiatetradec-11-enoic acids, (Z,E)-13-thiatetradeca-9,11-dienoic acid, 11-thiadodecanoic acid, (E)- and (Z)-11-thiadodec-9-enoic acids and 15-thiahexadecanoic acid. 8-Thiatetradecanoic acid gave rise to two monoenoic thiafatty acids and two dienoic thiafatty acids, which were assigned to (Z)- and (E)-8-thiatetradec-11-enoic acids, (Z,E)-8-thiatetradeca-9,11-dienoic acid and (E,E)-8-thiatetradeca-10,12-dienoic acid. The other thiafatty acids tested, 9-, 10-, 11- and 12-thiatetradecanoic acids, were not metabolized by desaturation, although the corresponding products of beta-oxidation and chain elongation were detected. The occurrence of sulfoxides was not detected in this case, in disagreement with results on the metabolism of some thiaacids previously reported by other authors in yeast, Saccharomyces cerevisiae.
Asunto(s)
Ácidos Mirísticos/metabolismo , Atractivos Sexuales/biosíntesis , Spodoptera/metabolismo , Compuestos de Azufre/metabolismo , Animales , Glándulas Exocrinas/metabolismo , Ácidos Grasos Insaturados/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Ácidos Mirísticos/química , Compuestos de Azufre/químicaRESUMEN
Moth pheromone glands contain desaturases that catalyze the formation of conjugated dienoic fatty acids. In this article we present the first stereochemical study on one of these enzymes, namely the Delta(9) desaturase of (E)-11-tetradecenoic acid, using the moth Spodoptera littoralis as a biological model and enantiopure deuterated probes derived from tridecanoic acid. Gas chromatography coupled to mass spectrometry analysis of methanolyzed lipidic extracts from glands incubated with each individual probe showed that in the transformation of (E)-11-tetradecenoic acid into (Z,E)-9,11-tetradecadienoic acid both pro-(R) hydrogen atoms at C9 and C10 are removed from the substrate.
Asunto(s)
Ácido Graso Desaturasas/metabolismo , Ácidos Grasos Monoinsaturados/metabolismo , Ácidos Grasos Insaturados/metabolismo , Atractivos Sexuales/biosíntesis , Animales , Conformación Molecular , Spodoptera/metabolismo , Estearoil-CoA DesaturasaRESUMEN
(Z)-11-Hexadecenyl acetate, the main pheromone component of Sesamia nonagrioides sex pheromone, is biosynthesized from palmitic acid by Delta(11)-desaturation followed by reduction and acetylation. Production of (Z)-11-hexadecenyl acetate is regulated by the Pheromone Biosynthesis Activating Neuropeptide (PBAN). Transformation of (Z)-11-hexadecen-1-ol into the corresponding acetate is a target step for PBAN in the regulation of this biosynthetic sequence, thus being the first example of a PBAN-activated acetylation. The production of the minor component (Z)-11-hexadecenal is also stimulated by PBAN. The usefulness of pentafluorobenzyloxime-derivatives for the analysis of aldehyde pheromone constituents by gas chromatography coupled to mass spectrometry is also reported.
Asunto(s)
Hidroxilaminas/síntesis química , Neuropéptidos/metabolismo , Atractivos Sexuales/biosíntesis , Animales , Femenino , Estructura Molecular , Mariposas Nocturnas , Atractivos Sexuales/químicaRESUMEN
The structure of the hypertrehalosemic neuropeptide of the German cockroach, Blattella germanica, was found to be identical to that of the cockroach species, Blaberus discoidalis and Nauphoeta cinerea (Glp-Val-Asn-Phe-Ser-Pro-Gly-Trp-Gly-Thr-NH2). Since Blattella germanica is not closely related to Blaberus discoidalis and Nauphoeta cinerea, this supports the hypothesis that in this peptide family evolution of peptide structure may be related to evolution of peptide function.
Asunto(s)
Cucarachas/análisis , Neuropéptidos/química , Secuencia de Aminoácidos , Animales , Cucarachas/clasificación , Datos de Secuencia Molecular , Mapeo Peptídico , Especificidad de la EspecieRESUMEN
The synthesis of new acetylenic and cyclopropane fatty acids, as potential inhibitors of the beta-oxidation step in the proposed biosynthesis of the sex pheromone of the Egyptian armyworm Spodoptera littoralis, is reported. The biological activity of the compounds has been determined by in vitro and in vivo bioassays, and among all the compounds tested, dichlorocyclopropane acid has shown the highest inhibition activity displayed so far.
Asunto(s)
Ácidos Grasos/farmacología , Atractivos Sexuales/antagonistas & inhibidores , Animales , Ácidos Grasos/síntesis química , Ácidos Grasos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Mariposas Nocturnas , Espectrofotometría InfrarrojaRESUMEN
Lipid extracts of Spodoptera littoralis pheromone glands submitted to acid methanolysis using: (i) sulfuric acid/methanol/benzene (0.1:4:2, by vol) at 90 degrees C for 1 h; (ii) 12 N HCI/methanol (1:2, vol/vol) at 90 degrees C for 1 h, or (iii) 14% BF3-MeOH at 90 degrees C for 1 h did not reveal the presence of either 11- or 12-hydroxytetradecanoic acid in the extracts, as concluded from the gas chromatography-mass spectrometry analyses. Under the above methanolysis conditions, a synthetic sample of methyl (14, 14, 14-2H3) 12-hydroxytetradecanoate remained unaltered. These results may indicate that formation of (E)-11-tetradecenoic acid from tetradecanoic acid does not occur in the pheromone gland by dehydration of an intermediate hydroxyacid. Acid methanolysis of a lipidic extract using BF3-MeOH led to the formation of a mixture of methoxy fatty acid methyl esters, identified by gas chromatography-mass spectrometry. These methoxy derivatives should arise from BF3-catalyzed addition of methanol to the double bond of the natural monounsaturated fatty acyl derivatives present in the gland. Thus, under the same conditions, a synthetic sample of methyl (Z)-11-tetradecenoate was partially transformed into methyl 11-methoxytetradecanoate and methyl 12-methoxytetradecanoate. This reaction might be a useful alternative procedure to obtain methoxy derivatives of olefins, which are very helpful for the structural characterization of the parent alkenes.
Asunto(s)
Miristatos/análisis , Feromonas/química , Animales , Cromatografía de Gases y Espectrometría de Masas , Hidroxilación , Feromonas/metabolismo , SpodopteraRESUMEN
Sertaconazole is a pharmaceutical product in the form of a cream, gel, powder and solution for dermatological use and vaginal cream, tablets and ovules for gynecological use. It is marketed in 24 countries and registered in a further 22. The active ingredient is 2% sertaconazole nitrate. Sertaconazole nitrate is an azole antifungal agent, with notable antifungal activity. Its molecule has a highly lipophilic fragment. This is a review of the efficacy and safety of all pharmaceutical forms of sertaconazole in order to provide data on vaginal sertaconazole for marketing purposes.
Asunto(s)
Antifúngicos/uso terapéutico , Candidiasis Vulvovaginal/tratamiento farmacológico , Dermatomicosis/tratamiento farmacológico , Imidazoles/uso terapéutico , Micosis/tratamiento farmacológico , Tiofenos/uso terapéutico , Femenino , Humanos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
The high prevalence of beta-thalassemia minor and the occurrence of thalassemia major in Minorca prompted us to develop a prevention campaign. The selected population consisted of primary school students. The campaign was operative during the terms 1986-87 and 1987-88 and had three stages: 1.) informative; 2.) analytical study and diagnosis of carriers; 3.) report of the results and genetic counselling. We studied overall 1862 schoolchildren. The prevalence of beta-thalassemia minor was 3.38%. We discuss the methodology, the results and the effectiveness of the campaign.
Asunto(s)
Talasemia/epidemiología , Adolescente , Femenino , Tamización de Portadores Genéticos , Humanos , Masculino , Tamizaje Masivo , España/epidemiología , Talasemia/genética , Talasemia/prevención & controlRESUMEN
Researches related in this study were done on normal optic papillae. Their aim is to measure: a) the surface of the optic disc, the surface of the cup and the surface of the rim surrounding the cup; b) the depth of the cup; c) the diameters of the disc, the diameters of the cup and the width of the rim. Photographs were taken with a stereoscopic fundus camera and analysed by photogrammetry. There is a positive correlation between: a) the surface of the disc and the surface of the cup; b) the surface of the disc and the surface of the rim; c) the surface of the disc and the depth of the cup; d) the diameters of the disc and the diameters of the cup. There is no correlation between the diameter of the disc and the width of the rim. The ratio C/D is high when the disc is large.
Asunto(s)
Disco Óptico/anatomía & histología , Humanos , Fotogrametría , FotograbarRESUMEN
CASE REPORT: This case report presents a 36 year-old male with a sudden loss of vision while taking part in an expedition in the Daulaghiri (8,167 metres high peak located in the Himalayan Mountain Range). DISCUSSION: High altitude retinal haemorrhage is a common condition in those mountaineers who reach altitudes over 5,500m. Depending on its location it may not present any symptoms and the condition improves with no further complications. However, in case of macular involvement the vision decreases dramatically and the consequences are uncertain.