Contaminación atmosférica en Dock Sud, pcia. de Buenos Aires, Argentina : Análisis de su comportamiento temporal en el período 2011-2017

El Polo Petroquímico de Dock Sud es considerado un ícono de la contaminación en el Riachuelo. Desde finales del año 2010, se lleva adelante un monitoreo de la calidad de aire. El objetivo de este trabajo es caracterizar el comportamiento temporal de los contaminantes atmosféricos (NO, NO2, NOx, O3, CO, COVs, SO2, PM10 y PM2.5) medidos en el área de Dock Sud, Pcia. de Buenos Aires. Para ello se utilizó información de la estación de monitoreo continuo y automático EMC I Dock Sud, provista por ACUMAR, del período comprendido entre enero de 2011 y febrero de 2017. Se elaboró un análisis temporal de los contaminantes, que incluyó el estudio de las concentraciones en función de distintas variables ambientales y su comparación con normativas vigentes. PM10, PM2.5, O3 y SO2 sobrepasaron los niveles guía de OMS en múltiples oportunidades al cabo de un año.Centro de Investigaciones del Medio Ambient

Historical Archaeology in the Iberian Peninsula

UID/HIS/04209/2019 DL 57/2016/CP1453/CT0084authorsversionpublishe

Differential effects of combined trk receptor mutations on dorsal root ganglion and inner ear sensory neurons

We have generated double mutant mice deficient in pairs of two different Trk receptors and have analysed the effects on survival and differentiation of dorsal root ganglion (DRG), inner ear cochlear and vestibular sensory neurons, In most combinations of mutant trk alleles, the defects observed in double compared to single mutant mice were additive. However, double homozygous trkA(-/-);trkB(-/-)DRG and trkB(-/-);trkC(-/-) vestibular neurons showed the same degree of survival as single trkA(-/-) and trkB(-/-) mice, respectively, suggesting that those neurons required both Trk signaling pathways for survival, In situ hybridisation analysis of DRG neurons of double mutant mice revealed differential expression of excitatory neuropeptides. Whereas calcitonin-gene-related peptide expression correlated with the trkA phenotype, substance P expression was detected in all combinations of double mutant mice. In the inner ear, TrkB- and TrkC-dependent neurons were shown to at least partially depend on each other for survival, most likely indirectly due to abnormal development of their common targets. This effect was not observed in DRGs, where neurons depending on different Trk receptors generally innervate different targets

Survival of inner ear sensory neurons in trk mutant mice

Analysis of trkB(-/-); trkC(-/-) double mutant mice revealed that peripheral and central inner ear sensory neurons are affected in these mice. However, a substantial amount of cochlear and vestibular neurons survive, possibly due to maintenance or upregulation of TrkA expression. To clarify the function of the TrkA receptor during development of the cochlear and vestibular ganglion we analysed trkA(-/-) mice and the expression of this receptor in inner ear sensory neurons of trkB(-/-); trkC(-/-) animals. TrkA homozygous mutant mice showed normal numbers of neurons and no TrkA expression was detected in neurons of trkB(-/-); trkC(-/-) double mutant mice. We conclude that TrkA is not essential for inner ear development and that in the absence of any of the known catalytic Trk receptors peripheral inner ear sensory neurons are prone to undergo cell death or must use a different signaling mechanism to survive. (C) 1997 Elsevier Science Ireland Ltd

Developing inner ear sensory neurons require TrkB and TrkC receptors for innervation of their peripheral targets

The trkB and trkC genes are expressed during the formation of the vestibular and auditory system. To elucidate the function of trkB and trkC during this process, we have analysed mice carrying a germline mutation in the tyrosine kinase catalytic domain of these genes. Neuroanatomical analysis of homozygous mutant mice revealed neuronal deficiencies in the vestibular and cochlear ganglia. In trkB (-/-) animals vestibular neurons and a subset of cochlear neurons responsible for the innervation of outer hair cells were drastically reduced. The peripheral targets of the respective neurons showed severe innervation defects. A comparative analysis of ganglia from trkC (-/-) mutants revealed a moderate reduction of vestibular neurons and a specific loss of cochlear neurons innervating inner hair cells. No nerve fibres were detected in the sensory epithelium containing inner hair cells. A developmental study of trkB (-/-) and trkC (-/-) mice showed that some vestibular and cochlear fibres initially reached their peripheral targets but failed to maintain innervation and degenerated. TrkB and TrkC receptors are therefore required for the survival of specific neuronal populations and the maintenance of target innervation in the peripheral sensory system of the inner ear