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The latest Triassic was characterised by protracted biotic extinctions concluding in the End-Triassic Extinction (~ 200 Ma) and a global carbon cycle perturbation. The onset of declining diversity is closely related to reducing conditions that spread globally from upper Sevatian (uppermost Norian) to across the Norian-Rhaetian boundary, likely triggered by unusually high volcanic activity. We correlate significant organic carbon cycle perturbations to an increase of CO2 in the ocean-atmosphere system, likely outgassed by the Angayucham igneous province, the onset of which is indicated by the initiation of a rapid decline in 87Sr/86Sr and 188Os/187Os seawater values. A possible causal mechanism involves elevated CO2 levels causing global warming and accelerating chemical weathering, which increased nutrient discharge to the oceans and greatly increased biological productivity. Higher export production and oxidation of organic matter led to a global O2 decrease in marine water across the Norian/Rhaetian boundary (NRB). Biotic consequences of dysoxia/anoxia include worldwide extinctions in some fossil groups, such as bivalves, ammonoids, conodonts, radiolarians.
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Fósiles , Océanos y Mares , Agua de Mar , Agua de Mar/química , Extinción Biológica , Ciclo del Carbono , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análisis , Oxígeno/metabolismo , Atmósfera/química , AnimalesRESUMEN
OBJECTIVES: Motor neuron disease (MND) is an incurable progressive neurodegenerative disease with limited treatment options. There is a pressing need for innovation in identifying therapies to take to clinical trial. Here, we detail a systematic and structured evidence-based approach to inform consensus decision making to select the first two drugs for evaluation in Motor Neuron Disease-Systematic Multi-arm Adaptive Randomised Trial (MND-SMART: NCT04302870), an adaptive platform trial. We aim to identify and prioritise candidate drugs which have the best available evidence for efficacy, acceptable safety profiles and are feasible for evaluation within the trial protocol. METHODS: We conducted a two-stage systematic review to identify potential neuroprotective interventions. First, we reviewed clinical studies in MND, Alzheimer's disease, Huntington's disease, Parkinson's disease and multiple sclerosis, identifying drugs described in at least one MND publication or publications in two or more other diseases. We scored and ranked drugs using a metric evaluating safety, efficacy, study size and study quality. In stage two, we reviewed efficacy of drugs in MND animal models, multicellular eukaryotic models and human induced pluripotent stem cell (iPSC) studies. An expert panel reviewed candidate drugs over two shortlisting rounds and a final selection round, considering the systematic review findings, late breaking evidence, mechanistic plausibility, safety, tolerability and feasibility of evaluation in MND-SMART. RESULTS: From the clinical review, we identified 595 interventions. 66 drugs met our drug/disease logic. Of these, 22 drugs with supportive clinical and preclinical evidence were shortlisted at round 1. Seven drugs proceeded to round 2. The panel reached a consensus to evaluate memantine and trazodone as the first two arms of MND-SMART. DISCUSSION: For future drug selection, we will incorporate automation tools, text-mining and machine learning techniques to the systematic reviews and consider data generated from other domains, including high-throughput phenotypic screening of human iPSCs.
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Enfermedad de la Neurona Motora , Humanos , Consenso , Células Madre Pluripotentes Inducidas , Enfermedad de la Neurona Motora/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Oligodendrocytes are implicated in amyotrophic lateral sclerosis pathogenesis and display transactive response DNA-binding protein-43 (TDP-43) pathological inclusions. To investigate the cell autonomous consequences of TDP-43 mutations on human oligodendrocytes, we generated oligodendrocytes from patient-derived induced pluripotent stem cell lines harbouring mutations in the TARDBP gene, namely G298S and M337V. Through a combination of immunocytochemistry, electrophysiological assessment via whole-cell patch clamping, and three-dimensional cultures, no differences in oligodendrocyte differentiation, maturation or myelination were identified. Furthermore, expression analysis for monocarboxylate transporter 1 (a lactate transporter) coupled with a glycolytic stress test showed no deficit in lactate export. However, using confocal microscopy, we report TDP-43 mutation-dependent pathological mis-accumulation of TDP-43. Furthermore, using in vitro patch-clamp recordings, we identified functional Ca2+-permeable α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor dysregulation in oligodendrocytes. Together, these findings establish a platform for further interrogation of the role of oligodendrocytes and cellular autonomy in TDP-43 proteinopathy.
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Glyphosate is the most common herbicide worldwide, and its impact on the environment has increasingly been scrutinized. Glyphosate-based formulations can contain co-formulants, among which are surfactants. This study aimed to investigate whether the presence of an alkyl polyglucoside-based surfactant, Triton CG-110, affects the adsorption, leaching, and mineralisation of glyphosate in the soil. The experiments were conducted in two soils with different textures (sandy and clay) and in washed sand. Glyphosate and surfactant mixtures were applied at realistic field rates. Because of ponding and scarce leaching from the field soil, the leaching experiments were conducted only with washed sand. The results indicate a reduction of glyphosate adsorption in washed sand (from Kfâ¯=â¯13.5 to 3.99 µg1-1/n (ml)1/nâ¯g-1) and in sandy soil (from Kf = 165 to 90.8⯵g1-1/ n (ml)1/nâ¯g-1) when using a Triton CG-110 concentration of 0.5 %, which corresponds to that of a spraying solution applied in the field, whereas adsorption in clay soil was unaffected. Triton CG-110 did not significantly affect glyphosate leaching in washed sand or mineralisation in any of the tested soils. The results indicate that Triton CG-110 is unlikely to significantly affect the environmental fate of glyphosate in the soil at environmentally relevant concentrations.
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Glyphosate is the most used pesticide worldwide and its impact on the environment is becoming increasingly significant. Glyphosate and its main metabolite AMPA are frequently detected in streams and rivers. In this study, an analytical method is presented that combines Ultra-High Performance Liquid Chromatography with mass spectrometry (UHPLC-ESI-MS/MS) for glyphosate and AMPA analysis in environmental water samples. The method was developed starting from an application of Waters Corporation, and involves the use of an alternative derivatizing reagent, the commercially available AccQ·Tag™ Ultra Derivatization Kit (Waters Corporation, Milford, MA, USA). The kit contains the derivatizing reagent 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC). Derivatization takes place directly in the injection vial and no sample pre-concentration is needed. The derivatization is simple, quick and robust, which fits well within the needs of a routine method for the analysis of glyphosate and AMPA. Derivatized glyphosate and AMPA were recorded in positive ion mode. The method demonstrates a good linear relationship in the concentration range from 0.2 µg/L for glyphosate and 0.05 µg/L for AMPA to 100 µg/L and an accurate recovery. The method developed has been successfully applied to the determination of glyphosate and AMPA in 23 runoff water samples collected from a field in the Po Valley (North-East Italy), an agricultural area where glyphosate is widely used.
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Monitoreo del Ambiente/métodos , Agua Dulce/química , Glicina/análogos & derivados , Cromatografía Líquida de Alta Presión , Glicina/análisis , Italia , Espectrometría de Masas en Tándem , Contaminantes Químicos del Agua/análisis , GlifosatoRESUMEN
Vegetated buffer strips (VBS) are recognized as a cost-effective way to reduce agricultural nonpoint-source pollution. In agroecosystems with high field fragmentation, only narrow VBS that partially compromise farmers' revenue are accepted. This study aimed to identify some ecosystem services as provided by VBS in terms of soil and water quality, and VBS performance in terms of wood for energy purposes. Buffer strip design (3 vs. 6 m wide) and composition were considered to define best practices for wood use at the farm level and for the local firewood market. Results showed that yearly wood pole production was 0.5 t 100 m, on average, ranging between a minimum of 0.22 t 100 m and a maximum of 0.72 t 100 m per row. Wood production had negligible effects on farmers' revenue. By contrast, water quality was enhanced, especially with 6-m-wide VBS. Specific subsidies for the maintenance of VBS increased total income despite a reduction in crop production (-17.5% in 6-m VBS with two rows). Subsidies might be better quantified at a site-specific level by taking into account all ecosystem services that are provided by VBS. Promising solutions to increase farmers' income are related to the wood seasoning process for firewood production; reducing the moisture content to <25% before the start of the winter season increases its market value.
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Agricultura , Contaminación Difusa/prevención & control , Ríos , Madera , Ecosistema , Suelo , Contaminación del Agua/prevención & controlRESUMEN
This study evaluates the effect of sewage amendment (SA) on the dissipation of terbuthylazine, its degradation compound desethyl-terbuthylazine, and S-metolachlor in the soil. The experiment was conducted at Padua Experimental Farm (Italy). Herbicides dissipation was evaluated in soils differently fertilized for three years: with inorganic fertilizer, with sewage sludge, and with a combination of them. Terbuthylazine and S-metolachlor were applied on sorghum as a formulated product at a dose of 2.8 L ha-1, and their dissipation was followed for 2.5 months. The concentrations of herbicides and one metabolite in soil were analyzed by liquid chromatography-mass spectrometry. The dissipation of terbuthylazine and S-metolachlor followed a pseudo first order kinetics; they dissipated faster in soil amended only with inorganic fertilizer than in soils amended with sewage or sewage + inorganic fertilizer. The reduction in mineralization of the herbicides after sewage addition can be attributed to the reduced herbicide availability to microorganisms. The degradation of terbuthylazine led to the formation of desethyl-terbuthylazine. SA slowed down the formation and the degradation of desethyl-terbuthylazine, leading to a higher amount measured at the end of the incubation. These findings have practical implications for the assessment of the environmental fate of terbuthylazine and S-metolachlor in agricultural areas.
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Acetamidas/metabolismo , Herbicidas/metabolismo , Aguas del Alcantarillado , Contaminantes del Suelo/metabolismo , Triazinas/metabolismo , Acetamidas/química , Agricultura , Biodegradación Ambiental , Cromatografía Liquida , Fertilizantes , Herbicidas/química , Italia , Espectrometría de Masas , Suelo/química , Contaminantes del Suelo/análisis , Contaminantes del Suelo/química , Triazinas/químicaRESUMEN
This study evaluates the dissipation of terbuthylazine, metolachlor, and mesotrione at different depths in soils with contrasting texture. The field trial was conducted at the Padua University Experimental Farm, north-east Italy. The persistence of three herbicides was studied in three different soil textures (clay soil, sandy soil, and loamy soil) at two depths (0-5 and 5-15 cm). Soil organic carbon content was highest in the clay (1.10%) followed by loam (0.67%) and sandy soil (0.24%); the pH of soils was sub-alkaline. Terbuthylazine, metolachlor, and mesotrione were applied on maize as a formulated product (Lumax®) at a dose of 3.5 L ha-1. Their dissipation in the treated plots was followed for 2 months after application. The concentrations of herbicides were analyzed by liquid chromatography-mass spectrometry. The dissipation of terbuthylazine, metolachlor, and mesotrione could be described by a pseudo first-order kinetics. Terbuthylazine showed the highest DT50, followed by metolachlor and mesotrione. Considering the tested soil, the highest DT50 value was found in clay soil for terbuthylazine and metolachlor, whereas for mesotrione there was no difference among soils. Significant differences were found between the two soil depths for terbuthylazine and metolachlor, whereas none were found for mesotrione. These results suggest that soil texture and depth have a strong influence on the dissipation of terbuthylazine and metolachlor, whereas no influence was observed on mesotrione because of its chemical and physical properties.
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Acetamidas/química , Ciclohexanonas/química , Herbicidas/química , Contaminantes del Suelo/química , Suelo/química , Triazinas/química , Zea mays/química , Monitoreo del Ambiente , Herbicidas/análisis , Italia , Contaminantes del Suelo/análisisRESUMEN
In intensive agricultural systems runoff is one of the major potential diffuse pollution pathways for pesticides and poses a risk to surface water. Ditches are common in the Po Valley and can potentially provide runoff mitigation for the protection of watercourses. The effectiveness depends on ditch characteristics, so there is an urgent need for site-specific field trials. The use of a fugacity model (multimedia model) can allows recognition of the mitigation main processes. A field experiment was conducted in order to evaluate the mitigation capacity of a typical vegetated ditch, and results were compared with predictions by a fugacity model. To evaluate herbicide mitigation after an extreme runoff, the ditch was flooded with water containing mesotrione, S-metolachlor and terbuthylazine. Two other subsequent floods with uncontaminated water were applied 27 and 82 days later to evaluate herbicides release. Results show that the ditch can immediately reduce runoff concentration of herbicides by at least 50% even in extreme flooding conditions. The half-distances were about 250 m. As a general rule, a runoff of 1 mm from 5 ha is mitigated by 99% in 100 m of vegetated ditch. Herbicides retention in the vegetated ditch was reversible, and the second flood mobilized 0.03-0.2% of the previous one, with a concentration below the drinking water limit of 0.1 µg L(-1). No herbicide was detected in the third flood, because the residual amount in the ditch was too low. Fugacity model results show that specific physical-chemical parameters may be used and a specific soil-sediment-plant compartment included for modelling herbicides behaviour in a vegetated ditch, and confirm that accumulation is low or negligible for herbicides with a half-life of 40 days or less. Shallow vegetated ditches can thus be included in a general agri-environment scheme for the mitigation of pesticides runoff together with wetlands and linear buffer strips. These structures are present in the landscape, and their environmental role can be exploited by proper management.
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Plaguicidas/toxicidad , Contaminación Química del Agua/prevención & control , Agricultura/métodos , Conservación de los Recursos Naturales , Drenaje de Agua/métodos , Inundaciones , Semivida , Herbicidas/farmacocinética , Herbicidas/toxicidad , Italia , Modelos Teóricos , Plaguicidas/farmacocinética , Plantas/metabolismo , Gestión de Riesgos , Suelo/química , Contaminantes Químicos del Agua/farmacocinética , Contaminantes Químicos del Agua/toxicidadRESUMEN
In alpine environments, colonies of snow vole (Chionomys nivalis Martins) cause strong pedoturbation, which may affect humification process and soil organic matter (SOM) cycling, with repercussions on the hormone-like activity of organics. We investigated the effect of snow vole pedoturbation on the chemical and spectroscopic features of soil organic fractions, and the potential hormone-like activity of humic and fulvic acids (HA, FA). The study site was located on the high-mountain environment of the Majella massif (central Italy). Pedoturbated and regular soils were morphologically described and characterized for pH and content of total organic carbon, total extractable carbon, HA, and FA. Both HA and FA were extracted and investigated using attenuated total reflectance/Fourier transform infrared (ATR/FTIR), nuclear magnetic resonance with high-resolution magic angle spinning (HRMAS-NMR), and (1)H-(13)C heteronuclear single quantum coherence (HSQC). HA and FA were also tested for their auxin-like and gibberellin-like activities. Results provide evidences that bioturbated and regular soils contain a poorly decomposed SOM, but HA and FA with a well-defined molecular structure. The HA and FA from both bioturbated and regular soils show a hormone-like activity with a different allocation along the soil profile. In the regular soil, the highest auxin-like activity was shown by HA and FA from Oe1 horizon, while gibberellin-like activity was expressed by FA from Oe2 horizon. Burrowing activity determines a redistribution of organics throughout the profile with a relatively high auxin-like activity in the FA from straw tunnel wall (STW) and gibberellin-like activity in the HA from vole feces (VF). The relative high presence of carboxylic acids, amides, proteins, and amino acids in the FA from STW and the aromatic moieties in the HA from VF put evidences for their different behavior. The fact that snow vole activity has modified the chemical and biological properties of SOM in these soils otherwise considered governed only by low temperature has important ecological implications such as the preservation of soil fertility and vegetal biodiversity.
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INTRODUCTION: In intensive agriculture areas the use of pesticides can alter soil properties and microbial community structure with the risk of reducing soil quality. MATERIALS AND METHODS: In this study the fatty acid methyl esters (FAMEs) evolution has been studied in a factorial lab experiment combining five substrates (a soil, two aged composts and their mixtures) treated with a co-application of three pesticides (azoxystrobin, chlorotoluron and epoxiconazole), with two extraction methods, and two incubation times (0 and 58 days). FAMEs extraction followed the microbial identification system (MIDI) and ester-linked method (EL). RESULTS AND DISCUSSION: The pesticides showed high persistence, as revealed by half-life (t1/2) values ranging from 168 to 298 days, which confirms their recalcitrance to degradation. However, t1/2 values were affected by substrate and compost age down to 8 days for chlorotoluron in S and up to 453 days for epoxiconazole in 12M. Fifty-six FAMEs were detected. Analysis of variance (ANOVA) showed that the EL method detected a higher number of FAMEs and unique FAMEs than the MIDI one, whereas principal component analysis (PCA) highlighted that the monosaturated 18:1ω9c and cyclopropane 19:0ω10c/19ω6 were the most significant FAMEs grouping by extraction method. The cyclopropyl to monoenoic acids ratio evidenced higher stress conditions when pesticides were applied to compost and compost+soil than solely soil, as well as with final time. CONCLUSION: Overall, FAMEs profiles showed the importance of the extraction method for both substrate and incubation time, the t1/2 values highlighted the effectiveness of solely soil and the less mature compost in reducing the persistence of pesticides.
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Ácidos Grasos/análisis , Plaguicidas/análisis , Suelo/química , Monitoreo del Ambiente , Compuestos Epoxi/análisis , Semivida , Metacrilatos/análisis , Compuestos de Fenilurea/análisis , Pirimidinas/análisis , Microbiología del Suelo , Estrobilurinas , Factores de Tiempo , Triazoles/análisisRESUMEN
Narrow vegetative filter strips proved to effectively reduce herbicide runoff from cultivated fields mainly due to the ability of vegetation to delay surface runoff, promote infiltration and adsorb herbicides. A field trial was conducted from 2007 to 2009 in north-east Italy in order to evaluate the effectiveness of various types of vegetative filter strips to reduce spring-summer runoff of the herbicides mesotrione, metolachlor and terbuthylazine, widely used in maize, and to evaluate the effect of the rainfall characteristics on the runoff volume and concentration. Results show that without vegetative filter strip the herbicide load that reaches the surface water is about 5-6 g ha(-1)year(-1) for metolachlor and terbuthylazine (i.e. 0.5-0.9% of the applied rate), confirming that runoff from flat fields as in the Po Valley can have a minor effect on the water quality, and that most of the risk is posed by a few, or even just one extreme rainfall event with a return period of about 25-27 years, causing runoff with a maximum concentration of 64-77 µg L(-1). Mesotrione instead showed rapid soil disappearance and was observed at a concentration of 1.0-3.8 µg L(-1) only after one extreme (artificial) rainfall. Vegetative filter strips of any type are generally effective and can reduce herbicide runoff by 80-88%. Their effectiveness is steady even under severe rainfall conditions, and this supports their implementation in an environmental regulatory scheme at a catchment or regional scale.
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Herbicidas/química , Contaminantes Químicos del Agua/química , Acetamidas/química , Adsorción , Ciclohexanonas/química , Monitoreo del Ambiente , Filtración , Lluvia , Estaciones del Año , Suelo/química , Propiedades de Superficie , Triazinas/químicaRESUMEN
Compost biobeds can promote biodegradation of pesticides. The microbial community structure changes during the composting process, and simple methods can potentially be used to follow these changes. In this study the microbial identification (MIDI) and ester-linked (EL) procedures were used to determine the composition of fatty acid methyl esters (FAMEs) in composts aged 3 and 12 months, inoculated with 3 recalcitrant pesticides (azoxystrobin, chlorotoluron, and epoxyconazole and a coapplication of all three) after 0, 56, and 125 days of degradation. Pesticide persistence was high, and after 125 days the residue was 22 to 70% of the applied amount depending mostly on the composting age. Seventy-one FAMEs belonging to nine groups were detected. The EL method provided three times as many detections as did the MIDI method and was more sensitive for all FAME groups except alcohol. Thirty-six and five FAMEs were unique to the EL and MIDI methods, respectively. The extraction method was of importance. The EL method provided a higher number of detections for 57 FAMEs, and the MIDI method provided a higher number for 9 FAMEs, while the two methods were equal for 5 FAMEs; thus, the EL method provided a more uniform overall FAME profile. Effects of the other factors were not always clear. Inoculation with pesticide did not influence the FAME profile with the MIDI method, while it influenced cyclopropane and monounsaturated content with the EL method. Composting age and degradation time had an effect on some groups of FAMEs, and this effect was greater with the EL method. The use of some FAMEs as biomarkers to follow microbial community succession was likely influenced by the type of compost and other factors.
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Ácidos Grasos/análisis , Plaguicidas/metabolismo , Microbiología del Suelo , Suelo/química , Humanos , Factores de TiempoRESUMEN
A 180 d laboratory experiment was conducted to investigate the degradation rates of chlorpyrifos (10 and 50 mg kg(-1)) and metalaxyl (100 mg kg(-1)) separately and co-applied in a biomix constituted by topsoil, vine-branches and urban-waste-garden compost. The effect of repeated application of metalaxyl was also investigated. Microbial biomass-C (MBC) content and metabolic quotient (qCO(2)) were measured to evaluate changes in microbial biomass size and activity induced by the presence of the two pesticides. Degradation rate decreased with increasing concentration of chlorpyrifos in all treatments. Metalaxyl half-life was significantly reduced in co-application with chlorpyrifos indicating a synergic interaction between the two pesticides in favour of enhanced degradation rate for metalaxyl but not for chlorpyrifos. Furthermore, repeated application resulted in a sharp reduction of metalaxyl half-life from 37 d after first application to 4 d after third application. MBC content was negatively influenced by the addition of pesticides but it started to recover immediately, in both separate and co-applied treatments, reaching the control value when pesticide residues were about 50% of the initial concentration. The qCO(2) reached a steady-state after about 20 d in separately applied and 40 d in co-applied treatments, indicating a tendency to arrive at a new metabolic equilibrium. In conclusion, the biomix tested has been shown to degrade pesticides relatively fast and to have a microbial community that is varied enough to allow selection of those microorganisms able to degrade metalaxyl and chlorpyrifos.
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Plaguicidas/química , Alanina/análogos & derivados , Alanina/química , Alanina/metabolismo , Biodegradación Ambiental , Reactores Biológicos/microbiología , Cloropirifos/química , Cloropirifos/metabolismo , Plaguicidas/metabolismoRESUMEN
A field experiment is reported to ascertain the drift of two pesticides (chlorpyrifos and metalaxyl) in a vineyard in Italian climatic conditions and the effect of mitigation measures, such as buffer zones and tree rows, on pesticide drift contamination in a small aquatic system located inside the field. Results indicated that, in typical Italian agricultural conditions, spray drift in vineyards occurs at a distance of more than 24 m and adequate buffer zones are required to protect surface water bodies from direct contamination. The presence of tree rows in front of the water body inside the agricultural field, against the main wind direction, resulted in a very high reduction of the spray drift and of the ecotoxicological risk for aquatic ecosystem. In addition, a comparison between the data obtained in the experiment and the Drift Calculator procedure showed that the model failed when the procedure is used for short distances. However, concordance was found in terms of maximum drift distances.