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1.
Mar Pollut Bull ; 187: 114558, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36652856

RESUMEN

We report the occurrence of plastics and associated persistent organic pollutants (POPs) in surface waters from Northern Chilean Patagonia. A total of 200 particles were found during the conducted survey. The highest number of particles found was 0.6 item m-3. We found that 53 % of the collected particles corresponded to plastic, with an average of 0.19 ± 0.18 item m-3. Microplastics (68 %) were the dominant size found in the area, followed by macroplastics (18 %) and mesoplastics (14 %). Most plastic particles were white (55 %) while others were <10 % each. Black and light blue represented 9 %; red, dark blue, and other colors 7 %; and green 6 %. Fragments were the most frequent shape of plastic debris (38 %), followed by Styrofoam (30 %) and fiber (27 %). Higher PBDE levels were found in the central zone, and those were higher than DDT, PeCB, HCB, and PCB levels. This study is the first report on POP occurrence in marine plastic debris from Chiloé Sea in the Northern Chilean Patagonia.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Plásticos , Contaminantes Químicos del Agua/análisis , Chile , Monitoreo del Ambiente , Microplásticos
2.
Sci Total Environ ; 804: 150221, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34798745

RESUMEN

Warming trends in Patagonia and severe droughts in recent decades are still poorly understood in terms of their hydrological effects. The effects of climate change on water dynamics in addition to human water management could generate a future water scarcity scenario in one of the regions with the most abundant water resources of Chile. The aim of this work is to focus on assessing the impacts of warming trends on water dynamics in the Patagonian Simpson River watershed during the last two decades. We estimated anomalies in the main components of water balance such as precipitation (P), snow cover (SC), evapotranspiration (ET) and streamflows (Q) as well as surface variables and meteorological forcing (i.e. air temperature - Ta, solar radiation - RS, land surface temperature - LST). The processed data were obtained from remote sensing, reanalysis and in-situ data. We implemented a trend analysis for each variable in the period 2000-2019 at monthly, seasonal and annual scale. Results showed a warming trend in Ta and LST of about 1.2 °C and 2.1 °C, respectively, concentrated mainly in the autumn and winter seasons. Although P showed non-significant trends, Q diminished significantly at rates of more than 9.1 m3/s/decade, representing 36% of its historical mean. However, the decreases in Q are seen only in the maximum (spring) and minimum (summer) seasonal flows. These decreases are explained by significant increases in ET, led by a positive feedback of its drivers (LST, Ta and RS), which is directly linked to the impact of warming and an associated vegetation greenness in the watershed, as well as a decrease in SC during winter that feeds the Simpson River during spring and summer. The decrease in Q is reinforced by the intensification of water withdrawals in recent decades, as shown by an accelerated increase in water rights for agricultural and drinking uses. In a context of water scarcity and increasing and extreme droughts, this work contributes to further understanding water dynamics in western Patagonia, providing support for policy and decision-making when defining sustainable productive practices at watershed scale.


Asunto(s)
Monitoreo del Ambiente , Agua , Cambio Climático , Humanos , Ríos , Estaciones del Año
3.
Gene Ther ; 20(1): 69-83, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22278413

RESUMEN

Correction of perinatally lethal neurogenetic diseases requires efficient transduction of several cell types within the relatively inaccessible CNS. Intravenous AAV9 delivery in mouse has achieved development stage-specific transduction of neuronal cell types, with superior neuron-targeting efficiency demonstrated in prenatal compared with postnatal recipients. Because of the clinical relevance of the non-human primate (NHP) model, we investigated the ability of AAV9 to transduce the NHP CNS following intrauterine gene therapy (IUGT). We injected two macaque fetuses at 0.9 G with 1 × 10(13) vg scAAV9-CMV-eGFP through the intrahepatic continuation of the umbilical vein. Robust green fluorescent protein (GFP) expression was observed for up to 14 weeks in the majority of neurons (including nestin-positive cells), motor neurons and oligodendrocytes throughout the CNS, with a significantly lower rate of transduction in astrocytes. Photoreceptors and neuronal cell bodies in the plexiform and ganglionic retinal layers were also transduced. In the peripheral nervous system (PNS), widespread transduction of neurons was observed. Tissues harvested at 14 weeks showed substantially lower vector copy number and GFP levels, although the percentage of GFP-expressing cells remained stable. Thus, AAV9-IUGT in late gestation efficiently transduces both the CNS and PNS with neuronal predilection, of translational relevance to hereditary disorders characterized by perinatal onset of neuropathology.


Asunto(s)
Corteza Cerebral/metabolismo , Dependovirus/genética , Vectores Genéticos/administración & dosificación , Sistema Nervioso Periférico/metabolismo , Transducción Genética , Animales , Animales Recién Nacidos , Astrocitos/metabolismo , Citomegalovirus/genética , Femenino , Feto/metabolismo , Terapia Genética , Proteínas Fluorescentes Verdes/análisis , Proteínas Fluorescentes Verdes/genética , Macaca , Oligodendroglía/metabolismo , Embarazo , Retina/metabolismo
4.
Best Pract Res Clin Obstet Gynaecol ; 27(2): 209-19, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23062593

RESUMEN

Caesarean section incidence is steadily rising worldwide; the major contributor to this rise is pregnancies with previous caesarean section. Hence, it is important to scrutinise carefully the indication of primary caesarean sections. Preterm births, breech presentation and twin pregnancies together complicate 12-18% of all births. The role of caesarean section in these pregnancies is controversial and lacks good evidence-based guidelines. Policy on mode of delivery in these three important obstetric groups is bound to influence overall primary caesarean section rates. In this chapter, we review the evidence on the place of caesarean delivery in these three important groups.


Asunto(s)
Presentación de Nalgas/cirugía , Cesárea , Embarazo Gemelar , Nacimiento Prematuro/cirugía , Femenino , Humanos , Embarazo , Resultado del Tratamiento
6.
Plant Mol Biol ; 34(6): 879-89, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9290640

RESUMEN

The expression of Brazil nut storage albumin genes is highly regulated during seed development. Several sequences in the promoter of one of these genes show homologies with the target sites of the maize O2 bZIP regulatory protein. We therefore asked whether the O2 protein would recognize these promoter sequences. We show that the O2 protein binds to three different sequences (F1, F2 and F3). F1 and F3 are hybrid C/G and A/G boxes, respectively, that are homologous to the O2-binding site of a maize alpha-zein gene. F2 is a new O2-binding sequence related to the O2 target sites of the Coix alpha-coxin, the maize b-32 genes and the AP-1 pseudopalindrome. Molecular modelling showed that an Asn and a Ser in the 02 DNA binding domain make different base-specific contacts with each operator. 5' Promoter deletions of the be2S1 gene showed that the domain containing the O2 target sites F1 and F2 is required for detectable reporter gene expression in transgenic tobacco seeds. Moreover, the homologous coix O2 protein was shown to in situ transactivate the promoter region encompassing the three O2-binding sites F1, F2 and F3. Thus, these sites may be in vivo regulatory sequences mediating activation by bZIP regulatory proteins.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica de las Plantas , Nueces/genética , Proteínas de Plantas/genética , Regiones Promotoras Genéticas , Precursores de Proteínas/genética , Factores de Transcripción/metabolismo , Albuminas 2S de Plantas , Secuencia de Aminoácidos , Antígenos de Plantas , Secuencia de Bases , Sitios de Unión , Simulación por Computador , Huella de ADN , Leucina Zippers , Modelos Moleculares , Datos de Secuencia Molecular , Nueces/crecimiento & desarrollo , Proteínas de Plantas/metabolismo , Unión Proteica , Semillas/genética , Semillas/crecimiento & desarrollo , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Transformación Genética , Árboles/genética , Árboles/crecimiento & desarrollo
7.
An Med Interna ; 8(4): 185-7, 1991 Apr.
Artículo en Español | MEDLINE | ID: mdl-1912173

RESUMEN

A case of granulomatous peritonitis produced by starch is presented. This is a rare pathology caused by abdominal contamination with starch from surgical gloves during an operation. The symptoms can be very similar to acute abdomen, therefore, it is sometimes necessary to carry out a second operation in order to confirm the diagnosis. A peritoneal biopsy or cytology of the ascitic liquid usually provides the correct diagnosis as the typical starch granules show up. With non-steroid analgesics, or steroids in some cases, the process can controlled.


Asunto(s)
Granuloma/inducido químicamente , Peritonitis/inducido químicamente , Almidón/efectos adversos , Abdomen Agudo/diagnóstico , Adulto , Diagnóstico Diferencial , Femenino , Guantes Quirúrgicos , Granuloma/diagnóstico , Granuloma/cirugía , Humanos , Peritonitis/diagnóstico , Peritonitis/cirugía , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Reoperación
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