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1.
Sensors (Basel) ; 22(7)2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35408363

RESUMO

Soil spectroscopy in the visible-to-near infrared (VNIR) and mid-infrared (MIR) is a cost-effective method to determine the soil organic carbon content (SOC) based on predictive spectral models calibrated to analytical-determined SOC reference data. The degree to which uncertainty in reference data and spectral measurements contributes to the estimated accuracy of VNIR and MIR predictions, however, is rarely addressed and remains unclear, in particular for current handheld MIR spectrometers. We thus evaluated the reproducibility of both the spectral reflectance measurements with portable VNIR and MIR spectrometers and the analytical dry combustion SOC reference method, with the aim to assess how varying spectral inputs and reference values impact the calibration and validation of predictive VNIR and MIR models. Soil reflectance spectra and SOC were measured in triplicate, the latter by different laboratories, for a set of 75 finely ground soil samples covering a wide range of parent materials and SOC contents. Predictive partial least-squares regression (PLSR) models were evaluated in a repeated, nested cross-validation approach with systematically varied spectral inputs and reference data, respectively. We found that SOC predictions from both VNIR and MIR spectra were equally highly reproducible on average and similar to the dry combustion method, but MIR spectra were more robust to calibration sample variation. The contributions of spectral variation (ΔRMSE < 0.4 g·kg−1) and reference SOC uncertainty (ΔRMSE < 0.3 g·kg−1) to spectral modeling errors were small compared to the difference between the VNIR and MIR spectral ranges (ΔRMSE ~1.4 g·kg−1 in favor of MIR). For reference SOC, uncertainty was limited to the case of biased reference data appearing in either the calibration or validation. Given better predictive accuracy, comparable spectral reproducibility and greater robustness against calibration sample selection, the portable MIR spectrometer was considered overall superior to the VNIR instrument for SOC analysis. Our results further indicate that random errors in SOC reference values are effectively compensated for during model calibration, while biased SOC calibration data propagates errors into model predictions. Reference data uncertainty is thus more likely to negatively impact the estimated validation accuracy in soil spectroscopy studies where archived data, e.g., from soil spectral libraries, are used for model building, but it should be negligible otherwise.


Assuntos
Carbono , Solo , Calibragem , Carbono/química , Análise dos Mínimos Quadrados , Reprodutibilidade dos Testes , Solo/química
2.
Int J Mol Sci ; 22(2)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466918

RESUMO

DNA methylation changes may predispose becoming IgE-sensitized to allergens. We analyzed whether DNA methylation in peripheral blood mononuclear cells (PBMC) is associated with IgE sensitization at 5 years of age (5Y). DNA methylation was measured in 288 PBMC samples from 74 mother/child pairs from the birth cohort ALADDIN (Assessment of Lifestyle and Allergic Disease During INfancy) using the HumanMethylation450BeadChip (Illumina). PBMCs were obtained from the mothers during pregnancy and from their children in cord blood, at 2 years and 5Y. DNA methylation levels at each time point were compared between children with and without IgE sensitization to allergens at 5Y. For replication, CpG sites associated with IgE sensitization in ALADDIN were evaluated in whole blood DNA of 256 children, 4 years old, from the BAMSE (Swedish abbreviation for Children, Allergy, Milieu, Stockholm, Epidemiology) cohort. We found 34 differentially methylated regions (DMRs) associated with IgE sensitization to airborne allergens and 38 DMRs associated with sensitization to food allergens in children at 5Y (Sidak p ≤ 0.05). Genes associated with airborne sensitization were enriched in the pathway of endocytosis, while genes associated with food sensitization were enriched in focal adhesion, the bacterial invasion of epithelial cells, and leukocyte migration. Furthermore, 25 DMRs in maternal PBMCs were associated with IgE sensitization to airborne allergens in their children at 5Y, which were functionally annotated to the mTOR (mammalian Target of Rapamycin) signaling pathway. This study supports that DNA methylation is associated with IgE sensitization early in life and revealed new candidate genes for atopy. Moreover, our study provides evidence that maternal DNA methylation levels are associated with IgE sensitization in the child supporting early in utero effects on atopy predisposition.


Assuntos
Ilhas de CpG/genética , Metilação de DNA , Imunoglobulina E/sangue , Leucócitos Mononucleares/metabolismo , Mães/estatística & dados numéricos , Adulto , Alérgenos/imunologia , Células Cultivadas , Pré-Escolar , Estudos de Coortes , Feminino , Sangue Fetal/imunologia , Predisposição Genética para Doença/genética , Humanos , Hipersensibilidade/genética , Hipersensibilidade/imunologia , Imunoglobulina E/imunologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Masculino , Gravidez
3.
Environ Geochem Health ; 43(10): 4299-4313, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33860411

RESUMO

Pharmaceutically active compounds (PhACs) released into the environment have an adverse impact on the soil and water ecosystem as well as human health. Sorption of PhACs by soils and its potential modification through introduced DOM in the applied animal manure or treated wastewater (TWW) determines the mobility and environmental relevance of PhACs. Sulfadiazine, caffeine and atenolol were selected as target PhACs to investigate their sorption behaviors by five selected arable soils in the absence and presence of pig manure DOM. Sulfadiazine was least sorbed, followed by caffeine and atenolol according to the Freundlich sorption isotherm fit (soil average Kf [µg(1-n) mLn g-1] 4.07, 9.06, 18.92, respectively). The addition of manure DOM (31.34 mg C L-1) decreased the sorption of sulfadiazine and especially of caffeine and atenolol (average Kf 3.04, 6.17, 5.79, respectively). Freundlich sorption isotherms of the PhACs became more nonlinear in the presence of manure DOM (Freundlich exponent n changed from 0.74-1.40 to 0.62-1.12), implying more heterogeneous sorption of PhACs in soil-DOM binary systems. Sorption competition of DOM molecules with sulfadiazine and caffeine mostly contributed to their decreased soil sorption when DOM was present. In contrast, the formation of DOM-atenolol associates in the solution phase caused the largely decreased soil sorption of atenolol in the presence of DOM. It is suggested that DOM concentration (e.g., ≥ 60 mg C L-1) and its interaction with PhACs should be taken into consideration when assessing the environmental impact of land application of animal manure or irrigation with TWW.


Assuntos
Preparações Farmacêuticas , Poluentes do Solo , Adsorção , Animais , Atenolol , Cafeína , Ecossistema , Esterco , Solo , Poluentes do Solo/análise , Sulfadiazina , Suínos
5.
Environ Res ; 168: 14-24, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30253312

RESUMO

State of art metagenomics were used to investigate the microbial population, antibiotic resistance genes and plasmids of medical interest in wastewater used for urban agriculture in Ouagadougou (Burkina Faso). Wastewater samples were collected from three canals near agricultural fields in three neighbourhoods. Assessment of microbial population diversity revealed different microbial patterns among the different samples. Sequencing reads from the wastewaters revealed different functional specializations of microbial communities, with the predominance of carbohydrates and proteins metabolism functions. Eleven pathogen-specific and 56 orthologous virulence factor genes were detected in the wastewater samples. These virulence factors are usually found in human pathogens that cause gastroenteritis and/or diarrhoea. A wide range of antibiotic resistance genes was identified; 81 are transmissible by mobile genetic elements. These included seven different extended spectrum ß-lactamase genes encoding synthesis of four enzyme families, including two metallo-ß-lactamases (blaAIM-1 and blaGES-21). Ten different incompatibility groups of Enterobacteriaceae plasmid replicons (ColE, FIB, FIC, FII, P, Q, R, U, Y, and A/C), and 30 plasmid replicon types from Gram-positive bacteria. All are implicated in the wide distribution of antibiotic resistance genes. We conclude that wastewater used for urban agriculture in the city represents a high risk for spreading bacteria and antimicrobial resistance among humans and animals.


Assuntos
Irrigação Agrícola , Farmacorresistência Bacteriana , Fatores de Virulência , Águas Residuárias , Agricultura , Animais , Antibacterianos , Burkina Faso , Farmacorresistência Bacteriana/genética , Humanos , Fatores de Virulência/genética , Águas Residuárias/microbiologia , beta-Lactamases
6.
Ecotoxicol Environ Saf ; 178: 146-158, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31002969

RESUMO

Animal manure or bio-solids used as fertilizers are the main routes of antibiotic exposure in the agricultural land, which can have immense detrimental effects on plants. Sulfadiazine (SDZ), belonging to the class of sulfonamides, is one of the most detected antibiotics in the agricultural soil. In this study, the effect of SDZ on the growth, changes in antioxidant metabolite content and enzyme activities related to oxidative stress were analysed. Moreover, the proteome alterations in Arabidopsis thaliana roots in response to SDZ was examined by means of a combined iTRAQ-LC-MS/MS quantitative proteomics approach. A dose-dependent decrease in leaf biomass and root length was evidenced in response to SDZ. Increased malondialdehyde content at higher concentration (2 µM) of SDZ indicated increased lipid peroxidation and suggest the induction of oxidative stress. Glutathione levels were significantly higher compared to control, whereas there was no increase in ascorbate content or the enzyme activities of glutathione metabolism, even at higher concentrations. In total, 48 differentially abundant proteins related to stress/stimuli response followed by transcription and translation, metabolism, transport and other functions were identified. Several proteins related to oxidative, dehydration, salinity and heavy metal stresses were represented. Upregulation of peroxidases was validated with total peroxidase activity. Pathway analysis provided an indication of increased phenylpropanoid biosynthesis. Probable molecular mechanisms altered in response to SDZ are highlighted.


Assuntos
Antibacterianos/toxicidade , Arabidopsis/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteoma/metabolismo , Poluentes do Solo/toxicidade , Sulfadiazina/toxicidade , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Fertilizantes/análise , Esterco/análise , Proteômica/métodos , Solo/química
7.
PLoS Genet ; 10(1): e1004059, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24391521

RESUMO

Altered DNA methylation patterns in CD4(+) T-cells indicate the importance of epigenetic mechanisms in inflammatory diseases. However, the identification of these alterations is complicated by the heterogeneity of most inflammatory diseases. Seasonal allergic rhinitis (SAR) is an optimal disease model for the study of DNA methylation because of its well-defined phenotype and etiology. We generated genome-wide DNA methylation (N(patients) = 8, N(controls) = 8) and gene expression (N(patients) = 9, Ncontrols = 10) profiles of CD4(+) T-cells from SAR patients and healthy controls using Illumina's HumanMethylation450 and HT-12 microarrays, respectively. DNA methylation profiles clearly and robustly distinguished SAR patients from controls, during and outside the pollen season. In agreement with previously published studies, gene expression profiles of the same samples failed to separate patients and controls. Separation by methylation (N(patients) = 12, N(controls) = 12), but not by gene expression (N(patients) = 21, N(controls) = 21) was also observed in an in vitro model system in which purified PBMCs from patients and healthy controls were challenged with allergen. We observed changes in the proportions of memory T-cell populations between patients (N(patients) = 35) and controls (N(controls) = 12), which could explain the observed difference in DNA methylation. Our data highlight the potential of epigenomics in the stratification of immune disease and represents the first successful molecular classification of SAR using CD4(+) T cells.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Metilação de DNA/genética , Epigênese Genética , Rinite Alérgica Sazonal/genética , Adulto , Alérgenos/genética , Alérgenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Expressão Gênica , Genoma Humano , Humanos , Patologia Molecular , Pólen/imunologia , Rinite Alérgica Sazonal/imunologia , Rinite Alérgica Sazonal/patologia
8.
RNA ; 19(11): 1552-62, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24062574

RESUMO

MicroRNAs (miRNAs) play a key role in regulating mRNA expression, and individual miRNAs have been proposed as diagnostic and therapeutic candidates. The identification of such candidates is complicated by the involvement of multiple miRNAs and mRNAs as well as unknown disease topology of the miRNAs. Here, we investigated if disease-associated miRNAs regulate modules of disease-associated mRNAs, if those miRNAs act complementarily or synergistically, and if single or combinations of miRNAs can be targeted to alter module functions. We first analyzed publicly available miRNA and mRNA expression data for five different diseases. Integrated target prediction and network-based analysis showed that the miRNAs regulated modules of disease-relevant genes. Most of the miRNAs acted complementarily to regulate multiple mRNAs. To functionally test these findings, we repeated the analysis using our own miRNA and mRNA expression data from CD4+ T cells from patients with seasonal allergic rhinitis. This is a good model of complex diseases because of its well-defined phenotype and pathogenesis. Combined computational and functional studies confirmed that miRNAs mainly acted complementarily and that a combination of two complementary miRNAs, miR-223 and miR-139-3p, could be targeted to alter disease-relevant module functions, namely, the release of type 2 helper T-cell (Th2) cytokines. Taken together, our findings indicate that miRNAs act complementarily to regulate modules of disease-related mRNAs and can be targeted to alter disease-relevant functions.


Assuntos
MicroRNAs/genética , Rinite Alérgica Sazonal/genética , Células Th2/metabolismo , Carcinoma de Células Renais/genética , Diabetes Mellitus Tipo 2/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Interleucina-13/metabolismo , Interleucina-5/metabolismo , Neoplasias Renais/genética , MicroRNAs/metabolismo , Neoplasias Pancreáticas/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Doença Pulmonar Obstrutiva Crônica/genética , RNA Mensageiro , Células Th2/imunologia
9.
J Biol Chem ; 288(22): 16017-30, 2013 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-23564460

RESUMO

Nicotinic acid adenine dinucleotide phosphate (NAADP) is the most potent Ca(2+)-releasing second messenger known to date. Here, we report a new role for NAADP in arrhythmogenic Ca(2+) release in cardiac myocytes evoked by ß-adrenergic stimulation. Infusion of NAADP into intact cardiac myocytes induced global Ca(2+) signals sensitive to inhibitors of both acidic Ca(2+) stores and ryanodine receptors and to NAADP antagonist BZ194. Furthermore, in electrically paced cardiac myocytes BZ194 blocked spontaneous diastolic Ca(2+) transients caused by high concentrations of the ß-adrenergic agonist isoproterenol. Ca(2+) transients were recorded both as increases of the free cytosolic Ca(2+) concentration and as decreases of the sarcoplasmic luminal Ca(2+) concentration. Importantly, NAADP antagonist BZ194 largely ameliorated isoproterenol-induced arrhythmias in awake mice. We provide strong evidence that NAADP-mediated modulation of couplon activity plays a role for triggering spontaneous diastolic Ca(2+) transients in isolated cardiac myocytes and arrhythmias in the intact animal. Thus, NAADP signaling appears an attractive novel target for antiarrhythmic therapy.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Arritmias Cardíacas/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Isoproterenol/farmacologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , NADP/análogos & derivados , Animais , Arritmias Cardíacas/tratamento farmacológico , Arritmias Cardíacas/patologia , Células Cultivadas , Camundongos , Miocárdio/patologia , Miócitos Cardíacos/patologia , NADP/antagonistas & inibidores , NADP/metabolismo , Ácidos Nicotínicos/farmacologia , Canal de Liberação de Cálcio do Receptor de Rianodina/imunologia , Retículo Sarcoplasmático/metabolismo , Retículo Sarcoplasmático/patologia
10.
Appl Microbiol Biotechnol ; 98(14): 6487-95, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24743980

RESUMO

Sulfadiazine (SDZ) is an antibiotic frequently administered to livestock, and it alters microbial communities when entering soils with animal manure, but understanding the interactions of these effects to the prevailing climatic regime has eluded researchers. A climatic factor that strongly controls microbial activity is soil moisture. Here, we hypothesized that the effects of SDZ on soil microbial communities will be modulated depending on the soil moisture conditions. To test this hypothesis, we performed a 49-day fully controlled climate chamber pot experiments with soil grown with Dactylis glomerata (L.). Manure-amended pots without or with SDZ contamination were incubated under a dynamic moisture regime (DMR) with repeated drying and rewetting changes of >20 % maximum water holding capacity (WHCmax) in comparison to a control moisture regime (CMR) at an average soil moisture of 38 % WHCmax. We then monitored changes in SDZ concentration as well as in the phenotypic phospholipid fatty acid and genotypic 16S rRNA gene fragment patterns of the microbial community after 7, 20, 27, 34, and 49 days of incubation. The results showed that strongly changing water supply made SDZ accessible to mild extraction in the short term. As a result, and despite rather small SDZ effects on community structures, the PLFA-derived microbial biomass was suppressed in the SDZ-contaminated DMR soils relative to the CMR ones, indicating that dynamic moisture changes accelerate the susceptibility of the soil microbial community to antibiotics.


Assuntos
Antibacterianos/análise , Biota/efeitos dos fármacos , Esterco , Microbiologia do Solo , Solo/química , Água/análise , Animais , Antibacterianos/farmacologia , Clima , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Fosfolipídeos/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sulfadiazina/farmacologia
11.
J Environ Manage ; 141: 95-103, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24768839

RESUMO

Sulfonamides (SAs) are one of the most frequently used antibiotics in the veterinary industry, showing high mobility in soils. Objectives of this research were to determine the sorption, distribution coefficients and involvement of different ionic forms of sulfamethazine (SMZ), a representative SAs, and to evaluate the transport of SMZ in biochar treated soils. Biochars were produced from an invasive plant, burcucumber (Sicyos angulatus L.), under slow pyrolysis conditions at peak temperatures of 300 °C (biochar-300) and 700 °C (biochar-700), respectively. The abilities of the biochars to retain SMZ in loamy sand and sandy loam soils were examined under different pHs and SMZ loadings. Soil column experiments were performed with and without biochars addition. Results showed that biochar-700 had a high degree of SMZ retention, with resultant decreased pH in both soils. Modeled effective sorption coefficients (KD,eff) values indicated that the observed high SMZ retention at pH 3 could be attributed to the π-π electron donor-acceptor interaction and electrostatic cation exchange, whereas at pH 5 and 7, cation exchange was the main mechanisms responsible. There was no temporal retardation of SMZ in biochar treated soil as compared to the untreated soil. However, biochar-700 treatment achieved up to 89% and 82% increase in the SMZ retention in sandy loam and loamy sand soils, respectively. The overall results demonstrated that burcucumber biochar produced at higher temperature was effective in reducing the mobility of SMZ in the studied soils.


Assuntos
Antibacterianos/química , Carvão Vegetal , Cucurbitaceae , Poluentes do Solo/química , Sulfametazina/química , Gerenciamento de Resíduos/métodos , Adsorção , Agricultura , Antibacterianos/análise , Espécies Introduzidas , Poluentes do Solo/análise , Sulfametazina/análise , Temperatura
12.
Artigo em Inglês | MEDLINE | ID: mdl-37372741

RESUMO

Pharmaceutically active compounds (PhACs) enter soil with organic waste materials such as manure. Such complex substrates differently affect PhACs' soil sorption. For the first time, batch experiments were conducted using five selected chemicals as model constituents to elucidate the effects. Urea, phosphate (KH2PO4), acetic acid, phenol and nonadecanoic acid (C:19) altered the sorption strength and/or nonlinearity of sulfadiazine, caffeine, and atenolol in an arable Cambisol topsoil. The nonlinear Freundlich model best described sorption. Overall, the PhACs' Freundlich coefficients (sorption strength) increased in the sequence urea < phosphate < phenol < C:19 < acetic acid, while the Freundlich exponents largely decreased, indicating increasing sorption specificity. The effects on sulfadiazine and caffeine were rather similar, but in many cases different from atenolol. Phosphate mobilized sulfadiazine and caffeine and urea mobilized sulfadiazine, which was explained by sorption competition resulting from specific preference of similar sorption sites. Soil sorbed phenol strongly increased the sorption of all three PhACs; phenolic functional groups are preferred sorption sites of PhACs in soil. The large increase in sorption of all PhACs by acetic acid was attributed to a loosening of the soil organic matter and thus the creation of additional sorption sites. The effect of C:19 fatty acid, however, was inconsistent. These results help to better understand the sorption of PhACs in soil-manure mixtures.


Assuntos
Poluentes do Solo , Solo , Solo/química , Esterco , Atenolol , Cafeína , Adsorção , Sulfadiazina , Fenóis , Poluentes do Solo/análise , Preparações Farmacêuticas
13.
Artigo em Inglês | MEDLINE | ID: mdl-36767832

RESUMO

To identify the sources of contamination with potentially toxic elements (PTEs) in roadside orchard soils and to evaluate the potential ecological and environmental impacts in Gaziantep, soil samples from 20 mixed pistachio and olive orchards on roadsides with different traffic densities and at different distances to the roads were analyzed. Concentrations were 23,407.36 ± 4183.76 mg·kg-1 for Fe, 421.78 ± 100.26 mg·kg-1 for Mn, 100.20 ± 41.92 mg·kg-1 for Ni, 73.30 ± 25.58 mg·kg-1 for Cr, 65.03 ± 12.19 mg·kg-1 for Zn, 60.38± 7.91 mg·kg-1 for Pb, 17.74 ± 3.35 mg·kg-1 for Cu, 14.93 ± 4.94 mg·kg-1 for Co, and 0.30 ± 0.12 mg·kg-1 for Cd. It was found that the Ni content in 51% and the Cr content in 18% of orchard soils were above the legal limits for agricultural soils (pH > 6) in Türkiye. Factor analysis (FA) showed that Co, Cr, Cu, Fe, Mn, Ni, and Pb loaded on the first factor (FC1), while Cd and Zn loaded mostly on the second factor (FC2). It was found that Cr, Ni, and Pb were primarily enriched through pedogenic processes, whereas Cd most likely originated from agricultural activities, while the impact of road traffic as source of PTE contamination was insignificant. It has been revealed that the soils are of low quality for agricultural production due to PTE contamination (PIave ≥ 1). The SOPI values from environmental and ecological individual indices showed that the soil pollution level was moderate for Cd, Ni, and Pb, and low for Cr. The soil pollution index (SOPI) proved to be suitable for evaluating and comparing PTE pollution in regions with different soil properties.


Assuntos
Metais Pesados , Poluentes do Solo , Solo/química , Metais Pesados/análise , Monitoramento Ambiental , Cádmio/análise , Chumbo/análise , Poluentes do Solo/análise , Medição de Risco , China
14.
Sci Rep ; 13(1): 2818, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36797309

RESUMO

Redox-driven biogeochemical cycling of iron plays an integral role in the complex process network of ecosystems, such as carbon cycling, the fate of nutrients and greenhouse gas emissions. We investigate Fe-(hydr)oxide (trans)formation pathways from rhyolitic tephra in acidic topsoils of South Patagonian Andosols to evaluate the ecological relevance of terrestrial iron cycling for this sensitive fjord ecosystem. Using bulk geochemical analyses combined with micrometer-scale-measurements on individual soil aggregates and tephra pumice, we document biotic and abiotic pathways of Fe released from the glassy tephra matrix and titanomagnetite phenocrysts. During successive redox cycles that are controlled by frequent hydrological perturbations under hyper-humid climate, (trans)formations of ferrihydrite-organic matter coprecipitates, maghemite and hematite are closely linked to tephra weathering and organic matter turnover. These Fe-(hydr)oxides nucleate after glass dissolution and complexation with organic ligands, through maghemitization or dissolution-(re)crystallization processes from metastable precursors. Ultimately, hematite represents the most thermodynamically stable Fe-(hydr)oxide formed under these conditions and physically accumulates at redox interfaces, whereas the ferrihydrite coprecipitates represent a so far underappreciated terrestrial source of bio-available iron for fjord bioproductivity. The insights into Fe-(hydr)oxide (trans)formation in Andosols have implications for a better understanding of biogeochemical cycling of iron in this unique Patagonian fjord ecosystem.

15.
Chemosphere ; 312(Pt 1): 137210, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36368544

RESUMO

Manure is widely used as a fertilizer and applied to agricultural land. It may contain highly active chemicals like veterinary medicinal products or biocides, which enter into the environment by this pathway. This is recognized by several regulatory frameworks, however, a detailed method for examining the transformation of chemicals in manure was lacking. This article describes the validation of a method for studying the anaerobic transformation of chemicals in pig and cattle liquid manure. Different steps are covered with an emphasis on the validation ring test and the OECD (Organisation for Economic Cooperation and Development) process that led to the recent adoption of the method as OECD Test Guideline (TG) 320.


Assuntos
Esterco , Organização para a Cooperação e Desenvolvimento Econômico , Animais , Bovinos , Suínos , Anaerobiose , Fertilizantes , Agricultura
16.
Cytokine ; 60(3): 736-40, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22981205

RESUMO

The Th2 cytokine IL-13 plays a key role in allergy, by regulating IgE, airway hyper secretion, eosinophils and mast cells. In this study, we aimed to identify novel transcription factors (TFs) that potentially regulated IL-13. We analyzed Th2 polarized naïve T cells from four different blood donors with gene expression microarrays to find clusters of genes that were correlated or anti-correlated with IL13. These clusters were further filtered, by selecting genes that were functionally related. In these clusters, we identified three transcription factors (TFs) that were predicted to regulate the expression of IL13, namely CEBPB, E2F6 and AHR. siRNA mediated knockdowns of these TFs in naïve polarized T cells showed significant increases of IL13, following knockdown of CEBPB and E2F6, but not AHR. This suggested an inhibitory role of CEBPB and E2F6 in the regulation of IL13 and allergy. This was supported by analysis of E2F6, but not CEBPB, in allergen-challenged CD4+ T cells from six allergic patients and six healthy controls, which showed decreased expression of E2F6 in patients. In summary, our findings indicate an inhibitory role of E2F6 in the regulation of IL-13 and allergy. The analytical approach may be generally applicable to elucidate the complex regulatory patterns in Th2 cell polarization and allergy.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Fator de Transcrição E2F6/metabolismo , Interleucina-13/metabolismo , Rinite Alérgica Sazonal/metabolismo , Adulto , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteína beta Intensificadora de Ligação a CCAAT/genética , Linfócitos T CD4-Positivos/metabolismo , Análise por Conglomerados , Fator de Transcrição E2F6/genética , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Interleucina-5/análise , Ativação Linfocitária , Masculino , Interferência de RNA , RNA Interferente Pequeno , Receptores de Hidrocarboneto Arílico/genética , Rinite Alérgica Sazonal/genética , Rinite Alérgica Sazonal/imunologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Chemosphere ; 303(Pt 2): 135163, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35654230

RESUMO

Urea is the most commonly used nitrogen fertilizer worldwide. However, depending on soil and environmental conditions, high nitrogen losses can occur due to gaseous ammonia emissions. Urease inhibitors like N-(n-butyl)thiophosphoric triamide (NBPT) reduce these losses by blocking the urease enzyme, which catalyzes urea hydrolysis. With the increasing use of NBPT its environmental fate and features of urease inhibition become increasingly important. This study aimed to further elucidate major NBPT degradation pathways and related urease inhibition in soil. This was investigated in a 14-d incubation experiment using practice-relevant application rates of NBPT and four of its metabolites N-(n-butyl)phosphoric triamide (NBPTO), diamido phosphoric acid (DAP), diamido thiophosphoric acid (DATP) and rac-N-(n-butyl)thiophosphoric diamide (NBPD), covering three postulated degradation pathways. Additionally, the urease inhibition by these compounds was determined and further investigated in 2-h tests. The latter provided dose-response curves, showing that all substances inhibited urease, with NBPTO being the most effective. Inhibition of urease in NBPT-spiked soil was also largely, but not completely, attributed to NBPTO formed within the test period. In 14-d incubation tests, all investigated compounds dissipated quickly by >90% within 6 d (NBPTO), 3 d (NBPT) and ≤1 d (DAP, DATP and NBPD). Extensive oxidation of NBPT to NBPTO and subsequent minor formation of DAP was identified as the preferred degradation pathway. Abiotic degradation processes in sterile soil corresponded to 65-90% of total degradation in microbial active soil. Furthermore, pseudo-first order dissipation kinetics were retarded in sterile soil. Urease activity, calculated as a percentage of activity in the urea-fertilized control, was lowest after about 2 d when NBPTO was spiked to soil (17.9%), followed by NBPT (35.7%), DATP (51.3%), NBPD (54.0%), and DAP (54.4%). This shows that urease inhibition depends on the interplay of NBPT and its degradation products.


Assuntos
Solo , Urease , Fertilizantes/análise , Nitrogênio/metabolismo , Compostos Organofosforados/farmacologia , Ureia/metabolismo , Ureia/farmacologia
18.
Environ Pollut ; 292(Pt A): 118256, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34606970

RESUMO

Batch sorption of metformin hydrochloride (MET) onto a specially designed biochar mix consisting of both macro (MAC) and micro (MIC) algae, rice husk and pine sawdust was conducted. Pyrolysis of both MAC and MIC algae mixture was done followed by chemical activation with hydrogen-peroxide. Additionally, sorption of MET under the influence of pH was separately investigated. Batch studies of isotherms were well described by Freundlich model with high non-linearity and Freundlich exponent values ranged anywhere from 0.12 to 1.54. Heterogeneity of MET adsorption to the bonding sites was attributed to the surface functional groups of the modified biochar. Amongst the four biochars, the activated macroalgae biochar (MACAC) and microalgae biochar (MICAC) depicted favourable adsorption of MET with maximum adsorption at pH 7. Up to 76% of MET removal from the environment was obatained using the MACAC biochar. Scanning electron micrographs coupled with energy dispersive X-ray, as well as elemental analyses confirmed formation of oxygen containing surface functional groups due to activation strengthening chemisorption as the main sorption mechanism. Further, Fourier transform infra-red spectroscopy and other surface functional group analyses along with Zeta potential measurements reinforced our proposed sorption mechanism. Lowest zeta potential observed at pH 7 enhanced the electrostatic force of attraction for both the biochars. Negative zeta potential value of the biochars under different pH indicated potential of the biochars to adsorb other positively charged contaminants. From a techno-economic perspective, capital expenditure cost is not readily available, however, it is envisaged that production of pyrolyzed biochar from algal biomass could make the process economically attractive especially when the biochar could be utilised for high-end applications.


Assuntos
Metformina , Oryza , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Estudos de Viabilidade , Lignina , Poluentes Químicos da Água/análise
19.
Sci Total Environ ; 817: 152977, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35016939

RESUMO

Rock weathering and pedogenesis are fundamental processes for element mobility in terrestrial bio-geochemical cycles and for the regulation of primary productivity in adjacent coastal marine ecosystems. Here, soils developed from volcanic ash under extreme climate conditions could play a particular role. We therefore investigated rock weathering, soil formation and the associated mobilization of trace elements and micronutrients in a pristine South Patagonian ecosystem. Weathered and unweathered basement lithologies, tephra of the 4.216 kyrs BP Mt. Burney eruption and four soil profiles are considered. The approach combines mineralogical (XRD, SEM) and inorganic geochemical (XRF, ICP-OES/MS) with organic geochemical analyses (TOC, TN, δ13C, δ15N, DOC extracts) of representative samples. Chemical weathering is quantified by mass balance calculations and 14C age constraints allow a correlation of pedogenic processes with the paleoenvironmental history of the area. Our data document that pedogenesis with initial peat formation occurred since ~2.5 kyrs BP. In these acidic peaty Andosols, intensive alteration of volcanic glass mobilized large quantities of elements, considerably surpassing leachates provided by basement rock weathering. Clay production is limited in favor of the formation of amorphous Al- and crystalline Fe-(hydr)oxides. However, tephra alteration, soil organic matter turnover rates, enhanced dissolved organic carbon export, and Fe-/Al-(hydr)oxide precipitation are closely linked and ultimately controlled by rainfall-induced water-level fluctuations, highlighting the dominant influence of the southern westerly wind belt. The transport of mobilized trace elements and micronutrients adsorbed onto suspended colloids (dissolved organic carbon, Al-humus complexes and Fe-(hydr)oxides) is redox-pH-dependent, highly variable and ultimately regulated by westerly intensity. Broader implications of this work include a new perspective on the climate-controlled micronutrient delivery for primary productivity in South Patagonian fjords, which is strongly affected by Andosol formation. Furthermore, a careful evaluation of 'ordinary' geochemical proxies in regional paleoenvironmental archives is needed to account for these unique pedogenic processes.


Assuntos
Ecossistema , Solo , Clima , Solo/química , Erupções Vulcânicas , Tempo (Meteorologia)
20.
Appl Environ Microbiol ; 77(7): 2527-30, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21296942

RESUMO

Two soils were amended three times with pig manure. The abundance of sulfonamide resistance genes was determined by quantitative PCR 2 months after each application. In both soils treated with sulfadiazine-containing manure, the numbers of copies of sul1 and sul2 significantly increased compared to numbers after treatments with antibiotic-free manure or a control and accumulated with repeated applications.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Genes Bacterianos , Esterco , Metagenoma , Microbiologia do Solo , Sulfadiazina/farmacologia , Animais , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Proteínas de Escherichia coli/genética , Reação em Cadeia da Polimerase , Suínos
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