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1.
Public Health Nutr ; 24(12): 3662-3673, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33517942

RESUMEN

OBJECTIVE: We hypothesise that exposure to aflatoxins and fumonisins, measured in serum, alters protein synthesis, reducing serum protein and insulin-like growth factor 1 (IGF-1), increasing inflammation and infection, leading to child's linear growth failure. DESIGN: Children 6-35 months, stratified by baseline stunting, were subsampled from an intervention trial on quality protein maize consumption and evaluated at two time-points. SETTING: Blood samples and anthropometric data were collected in the pre-harvest (August-September 2015) and post-harvest (February 2016) seasons in rural Ethiopia. PARTICIPANTS: 102 children (50 stunted and 52 non-stunted). RESULTS: Proportions of children exposed to aflatoxin G1, aflatoxin G2 and aflatoxin M1 were higher in the pre-harvest (8, 33 and 7, respectively) compared to post-harvest season (4, 28 and 4, respectively). The proportion of children exposed to any aflatoxin was higher in the pre-harvest than post-harvest season (51 % v. 41 %). Fumonisin exposure ranged from 0 % to 11 %. In joint statistical tests, aflatoxin exposure was associated with serum biomarkers of inflammation (C-reactive protein, α-1-glycoprotein) and protein status (transthyretin, lysine, tryptophan), IGF-1 and linear growth (all P < 0·01). However, exposure to specific aflatoxins was not significantly associated with any biomarkers or outcomes (all P > 0·05). CONCLUSIONS: Aflatoxin exposure among rural Ethiopian children was high, with large variation between seasons and individual aflatoxins. Fumonisin exposure was low. There was no clear association between aflatoxin exposure and protein status, inflammation or linear growth. A larger study may be needed to examine the potential biological interactions, and the assessment of aflatoxins in food is needed to determine sources of high exposure.


Asunto(s)
Aflatoxinas , Fumonisinas , Niño , Etiopía , Contaminación de Alimentos/análisis , Fumonisinas/análisis , Fumonisinas/toxicidad , Humanos , Estudios Longitudinales
3.
Acta Neuropathol ; 138(3): 415-441, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31011860

RESUMEN

Multiple system atrophy (MSA) is characterized by the presence of distinctive glial cytoplasmic inclusions (GCIs) within oligodendrocytes that contain the neuronal protein alpha-synuclein (aSyn) and the oligodendroglia-specific phosphoprotein TPPP/p25α. However, the role of oligodendroglial aSyn and p25α in the formation of aSyn-rich GCIs remains unclear. To address this conundrum, we have applied human aSyn (haSyn) pre-formed fibrils (PFFs) to rat wild-type (WT)-, haSyn-, or p25α-overexpressing oligodendroglial cells and to primary differentiated oligodendrocytes derived from WT, knockout (KO)-aSyn, and PLP-haSyn-transgenic mice. HaSyn PFFs are readily taken up by oligodendroglial cells and can recruit minute amounts of endogenous aSyn into the formation of insoluble, highly aggregated, pathological assemblies. The overexpression of haSyn or p25α accelerates the recruitment of endogenous protein and the generation of such aberrant species. In haSyn PFF-treated primary oligodendrocytes, the microtubule and myelin networks are disrupted, thus recapitulating a pathological hallmark of MSA, in a manner totally dependent upon the seeding of endogenous aSyn. Furthermore, using oligodendroglial and primary cortical cultures, we demonstrated that pathology-related S129 aSyn phosphorylation depends on aSyn and p25α protein load and may involve different aSyn "strains" present in oligodendroglial and neuronal synucleinopathies. Importantly, this hypothesis was further supported by data obtained from human post-mortem brain material derived from patients with MSA and dementia with Lewy bodies. Finally, delivery of haSyn PFFs into the mouse brain led to the formation of aberrant aSyn forms, including the endogenous protein, within oligodendroglia and evoked myelin decompaction in WT mice, but not in KO-aSyn mice. This line of research highlights the role of endogenous aSyn and p25α in the formation of pathological aSyn assemblies in oligodendrocytes and provides in vivo evidence of the contribution of oligodendroglial aSyn in the establishment of aSyn pathology in MSA.


Asunto(s)
Atrofia de Múltiples Sistemas/patología , Proteínas del Tejido Nervioso/metabolismo , Sinucleinopatías/patología , alfa-Sinucleína/metabolismo , Animales , Encéfalo/metabolismo , Encéfalo/patología , Modelos Animales de Enfermedad , Humanos , Ratones , Ratones Transgénicos , Atrofia de Múltiples Sistemas/metabolismo , Neuronas/metabolismo , Neuronas/patología , Oligodendroglía/metabolismo , Ratas , Sinucleinopatías/metabolismo
4.
Environ Sci Pollut Res Int ; 23(20): 20517-20527, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27464655

RESUMEN

The environmental fate of metazachlor herbicide was investigated under field conditions in rapeseed cultivated and uncultivated plots, over a period of 225 days. The cultivation was carried out in silty clay soil plots with two surface slopes, 1 and 5 %. The herbicide was detectable in soil up to 170 days after application (DAA), while the dissipation rate was best described by first-order kinetics and its half-life ranged between 10.92 and 12.68 days. The herbicide was detected in the soil layer of 10-20 cm from 5 to 48 DAA, and its vertical movement can be described by the continuous stirred tank reactor (CSTR) in series model. Relatively low amounts of metazachlor (less than 0.31 % of the initial applied active ingredient) were transferred by runoff water. More than 80 % of the total losses were transferred at the first runoff event (12 DAA), with herbicide concentrations in runoff water ranging between 70.14 and 79.67 µg L-1. Minor amounts of the herbicide (less than 0.07 % of the initial applied active ingredient) were transferred by the sediment, with a maximum concentration of 0.57 µg g-1 (12 DAA), in plots with 5 % inclination. Finally, in rapeseed plants, metazachlor was detected only in the first sampling (28 DAA) at concentrations slightly higher than the limit of quantification; when in seeds, no residues of the herbicide were detected.


Asunto(s)
Acetamidas , Brassica rapa , Herbicidas , Movimientos del Agua , Contaminantes del Agua , Acetamidas/análisis , Acetamidas/química , Acetamidas/farmacocinética , Brassica rapa/química , Brassica rapa/metabolismo , Monitoreo del Ambiente , Herbicidas/análisis , Herbicidas/química , Herbicidas/farmacocinética , Contaminantes del Agua/análisis , Contaminantes del Agua/química , Contaminantes del Agua/farmacocinética
5.
Environ Sci Pollut Res Int ; 23(4): 3481-90, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26490927

RESUMEN

In the present study, the field dissipation and transport of quizalofop-p-ethyl by water and sediment runoff were investigated in sunflower experimental cultivation under Mediterranean conditions. The cultivation was carried out in silty clay soil plots with two different slopes of 1 and 5%. The soil dissipation rate of quizalofop-p-ethyl was fast and can be described by both single first-order (SFO) and Gustafson and Holden (first-order multi compartment (FOMC)) kinetics. The half-life of quizalofop-p-ethyl ranged from 0.55 to 0.68 days and from 0.45 to 0.71 days when SFO and FOMC kinetics were applied, respectively. No herbicide residues were detected below the 10-cm soil layer. A single detection of quizalofop-p-ethyl was observed in runoff water (3 days after application (DAA)) at relatively low concentrations (from 1.70 to 2.04 µg L(-1)). In sediment, it was detected in the samplings of 3 and 25 DAA at concentrations that never exceeded 0.126 µg g(-1). The estimated total losses of quizalofop-p-ethyl as percentage of the initial applied active ingredient were low both in water and sediment (less than of 0.021 and 0.005%, respectively). Quizalofop-p-ethyl residues were detectable for 18 DAA in the stems and leaves of the plants and 6 DAA in the root system. No herbicide residues were detected in inflorescences and seeds of sunflower plants. Experimental data showed minimal risk for the contamination of soil and adjacent water bodies.


Asunto(s)
Helianthus , Herbicidas/análisis , Residuos de Plaguicidas/análisis , Propionatos/análisis , Quinoxalinas/análisis , Contaminantes del Suelo/análisis , Flores/química , Semivida , Herbicidas/química , Residuos de Plaguicidas/química , Hojas de la Planta/química , Tallos de la Planta/química , Propionatos/química , Quinoxalinas/química , Semillas/química , Suelo/química , Contaminantes del Suelo/química , Agua/química
6.
Chemosphere ; 77(8): 1099-105, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19772980

RESUMEN

The degradation and mineralisation of (400 mL, 3.15 mM) aqueous solutions of 2-hydroxypyridine (2-HPY), a primary intermediate formed during the photolytic degradation of 2-chloropyridine (2-CPY), 2-bromopyridine (2-BPY) and 2-iodopyridine (2-IPY), was studied at 50 degrees C, under 254 nm UV irradiation in a range of conditions. The rate of 2-HPY disappearance was found to heavily depend on agitation, dissolved oxygen, pH and hydroxyl radical scavenger presence. pH has a pronounced effect on the phototreatment of 2-HPY, i.e. 2-HPY removal is faster at lower pH, but except for their influence on the solution pH, Cl(-) or F(-) do not appear to affect 2-HPY rate of removal or mineralisation. 2-HPY removal rate increases with dissolved oxygen, thus indicating a prominent 2-HPY photooxidation pathway. Helium purging of the solution before and during the measurement reduced 2-HPY removal rate, thus supporting the existence of a photooxidation pathway. Pure photolytic 2-HPY removal, i.e. when photooxidation is limited, fits pseudo-first order kinetics, and a kinetic model was developed for 2-HPY formation and removal during 2-CPY, 2-BPY and 2-IPY photolytic degradation under laminar flow. The addition of radical scavenger (tert-butanol) had a detrimental effect on the photolytic degradation of 2-HPY. Complete total organic carbon removal was achieved.


Asunto(s)
Fotólisis , Piridonas/química , Rayos Ultravioleta , Contaminantes Químicos del Agua/química , Cloro/química , Flúor/química , Depuradores de Radicales Libres/química , Concentración de Iones de Hidrógeno , Cinética , Modelos Químicos , Oxígeno/química
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