RESUMEN
UNLABELLED: Little information is available about the health risks associated with time spent in underground parking garages. The objective of this study was to determine whether it is possible to quantify the health risks associated with these garages without epidemiologic data on the subject. We followed the standard procedure for health risk assessment. We searched the literature for pollutant concentrations in the air samples of underground parking garages, the hazards associated with their inhalation, and their toxicological reference values. Conditions of occupational and user exposure were estimated by scenarios and taken into account to discuss toxicological reference values by modifying (with Haber's law) the adjustment factors for exposure frequency and duration. Risk quantification was possible for 39 pollutants. Acute exposures to CO and NO2 exceed toxicological reference values, as does chronic exposure to benzene for threshold effects. The risk of a carcinogenic effect associated with benzene may be greater than 10(-5). Excess exposure to air pollution indicators (PM and NO2) is also elevated, judging by the WHO Air Quality Guidelines, and also when comparing to levels with reported effects in epidemiologic studies. The risk associated with underground parking garages can be evaluated only in part. The information available is nonetheless sufficient to justify actions to reduce exposure. PRACTICAL IMPLICATIONS: The risks associated with exposure in underground parking garages cannot be thoroughly evaluated because of inadequate knowledge of exposures and of the toxicity of pollutants. The available knowledge is nonetheless sufficient to advise that risk management measures should be taken to reduce both acute and chronic exposures.
Asunto(s)
Contaminación del Aire Interior , Exposición Profesional/análisis , Estacionamientos , Humanos , Medición de RiesgoRESUMEN
A genomic DNA fragment containing the 5'-upstream sequence and part of the open reading frame corresponding to Triticum aestivum puroindoline-b cDNA, was isolated by inverse PCR. Promoter fragments extending to -1068, -388, -210 or -124 upstream of the translation initiation ATG codon and the sequence coding for the first 13 amino acids of the puroindoline-b, were translationally fused to the uidA reporter gene encoding beta-glucuronidase and transferred to rice calli via particle bombardment-mediated transformation. The 1068 bp and 124 bp promoters were also transcriptionally fused to the uidA reporter gene. Out of the 196 plants regenerated from transformed rice calli, 118 plants set seeds. No GUS activity was detectable in the stems, roots, leaves or pollen of the transgenic rice which had integrated the puroindoline-b promoter or its deletions; GUS activity was detected only in seeds, except in those having integrated the 124 bp promoter. Within seeds, histological localisation showed GUS activity as being restricted to the endosperm, aleurone cells and pericarp cell layers; no GUS activity was detected in the embryonic axis. Analysis of 5' promoter deletions identified the region between -388 and -210 as essential for endosperm expression, and the region between -210 and -124 as essential for expression in the epithelium of the scutellum. No difference of expression was observed between the translational and transcriptional fusion genes.
Asunto(s)
Regulación de la Expresión Génica de las Plantas , Oryza/genética , Proteínas de Plantas/genética , Regiones Promotoras Genéticas/genética , Semillas/genética , Triticum/genética , Secuencia de Bases , Biolística , Clonación Molecular , Endotelio/metabolismo , Genes Reporteros/genética , Datos de Secuencia Molecular , Especificidad de Órganos , Oryza/citología , Oryza/embriología , Oryza/crecimiento & desarrollo , Plantas Modificadas Genéticamente/genética , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes de Fusión , Eliminación de SecuenciaRESUMEN
A gene coding for a barley CMd protein was isolated from a genomic library using a cDNA probe encoding the wheat CM3 protein. Promoter sequence analysis reveals motifs found in genes specifically expressed in endosperm and aleurone cells, as well as TATA and other putative functional boxes. 720 bp of the Hv85.1 CMd protein gene promoter, when fused to a gus coding region, were unable to direct GUS activity in the seeds of transgenic tobacco plants. In contrast, the same construction delivered into immature maize kernels by microprojectile bombardment was able to direct expression of GUS in the outermost cell layers of maize endosperm in both a tissue-specific and a developmentally determined manner.
Asunto(s)
Hordeum/enzimología , Hordeum/genética , Nicotiana/genética , Proteínas de Plantas/genética , Plantas Tóxicas , Regiones Promotoras Genéticas , Zea mays/genética , Secuencia de Aminoácidos , Secuencia de Bases , Regulación de la Expresión Génica de las Plantas , Datos de Secuencia Molecular , Plantas Modificadas Genéticamente , Semillas/genética , Semillas/crecimiento & desarrollo , Transformación Genética , Inhibidores de Tripsina , Zea mays/crecimiento & desarrollo , alfa-Amilasas/antagonistas & inhibidoresRESUMEN
The CM (chloroform-methanol-soluble) proteins are low-molecular-weight cysteine-rich proteins that are found in wheat and barley endosperms. A cDNA clone encoding a Triticum durum (T. durum) CM3 protein has been isolated from a mid-maturation seed cDNA library. The T. durum CM3 protein is synthesized as a precursor including a signal peptide (SP) of 25 residues. Northern blot analysis shows that in developing seed the highest level of CM3 protein mRNA is detected at mid-maturation. The hybridization patterns obtained by Southern blot analysis indicated that T. durum CM proteins are encoded by a small multigene family. The similarity between the wheat and barley CM proteins encoded by homologous chromosomes is much higher than that between each of the three members of the T. durum family. All CM proteins contain ten cysteine residues organized in a conserved cysteine motif.
Asunto(s)
Proteínas de Plantas/química , Proteínas de Plantas/genética , Triticum/genética , Inhibidores de Tripsina/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Codón/genética , Regulación de la Expresión Génica de las Plantas , Hordeum/genética , Datos de Secuencia Molecular , Familia de Multigenes , Proteínas de Plantas/biosíntesis , ARN Mensajero/análisis , Semillas/genética , Homología de Secuencia de Ácido Nucleico , Factores de Tiempo , Triticum/metabolismoAsunto(s)
Proteínas de Plantas/genética , Triticum/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN , Sondas de ADN , Biblioteca Genómica , Datos de Secuencia Molecular , Señales de Clasificación de Proteína/genética , Homología de Secuencia de Ácido Nucleico , Especificidad de la EspecieRESUMEN
A Triticum durum cDNA library prepared from developing endosperm (22 days after flowering (DAF] was screened using synthetic oligonucleotide probes covering part of the CM3 and CM16 N-terminal protein sequences. A full-length cDNA clone (pTd78) encoding the CM16 protein (chloroform/methanol-soluble protein) was isolated and characterized. To our knowledge this is the first characterization of a clone coding for a wheat CM protein. The CM16 protein is synthesized as a preprotein with a signal peptide of 24 residues, the molecular weight of the mature protein being 13,438 Da. As other members of the cereal trypsin/alpha-amylase inhibitor family, the CM16 protein contains 10 cysteine residues, their position being well conserved. In developing endosperm the highest level of CM16 mRNA was detected at mid-maturation.
