RESUMEN
Air pollution and particulate matter (PM) are classified as carcinogenic to humans. Pollutants evidence for public health concern include coarse (PM10) and fine (PM2.5) particles. However, ultrafine particles (PM0.1) are assumed to be more toxic than larger particles, but data are still needed to better understand their mechanism of action. In this context, the aim of our work was to investigate the in vitro and in vivo genotoxic potential of fine (PM2.5-018) and quasi ultra-fine (PM0.18) particles from an urban-industrial area (Dunkirk, France) by using comet, micronucleus and/or gene mutation assays. In vitro assessment was performed with 2 lung immortalized cell lines (BEAS-2B and NCI-H292) and primary normal human bronchial epithelial cells (NHBE) grown at the air-liquid interface or in submerged conditions (5⯵g PM/cm2). For in vivo assessment, tests were performed after acute (24â¯h, 100⯵g PM/animal), subacute (1â¯month, 10⯵g PM/animal) and subchronic (3â¯months, 10⯵g PM/animal) intranasal exposure of BALB/c mice. In vitro, our results show that PM2.5-018 and PM0.18 induced primary DNA damage but no chromosomal aberrations in immortalized cells. Negative results were noted in primary cells for both endpoints. In vivo assays revealed that PM2.5-018 and PM0.18 induced no significant increases in DNA primary damage, chromosomal aberrations or gene mutations, whatever the duration of exposure. This investigation provides initial answers regarding the in vitro and in vivo genotoxic mode of action of PM2.5-018 and PM0.18 at moderate doses and highlights the need to develop standardized specific methodologies for assessing the genotoxicity of PM. Moreover, other mechanisms possibly implicated in pulmonary carcinogenesis, e.g. epigenetics, should be investigated.
Asunto(s)
Contaminación del Aire , Contaminantes Atmosféricos , Animales , Daño del ADN , Francia , Pulmón , Ratones , Ratones Endogámicos BALB C , Tamaño de la Partícula , Material ParticuladoRESUMEN
The axillary arch (AA) has been thoroughly studied and described as a supernumerary muscle, present unilaterally or bilaterally. This study aims to provide an in vivo demonstration of the influence of an AA on vascular, biometrical, and hemodynamic parameters. Two-hundred thirty-nine subjects with a mean age of 21.3 ± 2.7 years participated in this study. After visual screening by two independent experts, 20 subjects (8.4%) presented with an AA unilaterally (n = 12) or bilaterally (n = 8). An echo-Doppler examination of the vena and arteria axillaris was performed to measure blood flow, velocity of circulating elements, and blood vessel diameter in different positions of the arm (abduction: 45°, 90°, 90° combined with exorotation 'ER', 120°). The arteria axillaris parameters, measured in the test (n = 9; six women, three men) and control group (n = 11; six women, five men), were equivalent for all tested positions. The axillary vein parameters, compared to variations within the groups, revealed no significant differences. However, when comparing variation between groups, significant differences were found for (i) diameter in 90° abduction + ER and 120° abduction; (ii) velocity in 90° and 120° abduction. Blood flow demonstrated no significant difference between groups in any of the positions. The results of this study indicate that there is no functional vascular implication of the AA in the test samples. This study also questions the interpretation of some hypotheses regarding the AA and entrapment syndromes.
Asunto(s)
Axila/irrigación sanguínea , Músculo Esquelético/anomalías , Axila/anomalías , Estudios de Casos y Controles , Femenino , Hemodinámica , Humanos , Masculino , Adulto JovenRESUMEN
The study of several structural variations (the length, the degree of unsaturation and hydroxylation of the alkyl chains, the number and nature of osidic residues) helped understand the behaviour of neutral glycosphingolipids (GSLs) on porous graphitic carbon stationary phase (PGC). Atmospheric pressure photoionization mass spectrometry (APPI) and tandem mass spectrometry were used to perform the detection and the identification of molecular species in positive mode where [M+H](+) and [M-H(2)O+H](+) ions provided structural information on the fatty acid and the sphingoid base. The retention of GSLs increased with the hydrocarboneous volume of their alkyl chains and with the number of osidic residues in agreement with hydrophobic properties and polar retention effect of graphite, respectively. The presence of polar groups, such as OH-group or double bond within alkyl chains, decreased their retention. The coupling of chromatography on PGC with APPI tandem mass spectrometry detection appeared a powerful technique to discriminate isobaric molecules. Isobaric solutes differing by the position of two double bonds or by the repartition of hydrocarboneous skeleton were discriminated according to their chromatographic comportment or their mass spectrum, respectively. Among isobaric molecules, only few structures differing by the nature of osidic residue were not discriminated (i.e. glucosylceramide and galactosylceramide with similar ceramide skeleton were co-eluted and no difference in mass spectra was observed).
Asunto(s)
Cromatografía Liquida/métodos , Glicoesfingolípidos/análisis , Grafito/química , Presión Atmosférica , Secuencia de Carbohidratos , Datos de Secuencia MolecularRESUMEN
Seed beetles belonging to the Old World genus Caryedon feed in the seeds of various Caesalpinioideae, Mimosoideae, and Combretaceae. In an attempt to resolve broad phylogenetic relationships within the genus, we obtained 332 base pair sequences of mitochondrial 12S ribosomal DNA and morphological data for the 16 West African Caryedon species. Morphological characters were analyzed under maximum parsimony and sequences were compared under maximum parsimony, maximum likelihood, and neighbor joining. Using a partition homogeneity test, we determined that morphological and molecular data sets were combinable. Combined data were analyzed under maximum parsimony. Morphological and molecular trees were congruent at the species group level and total evidence analyses yielded the same topologies as molecular data with each of the three outgroups used. Four main terminal clades are recognized, each corresponding with a group of species generally feeding on the same host plant family, subfamily, genus, or species. The monophyly of legume feeding Caryedon is supported by both data sets, and Combretaceae feeders split in two monophyletic assemblages.