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1.
Sheng Wu Gong Cheng Xue Bao ; 37(8): 2936-2946, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34472310

RESUMO

A stable Zr-based metal-organic framework (MOF, UiO-66-NH2) synthesized via micro-water solvothermal method was used to immobilize amidase by using the glutaraldehyde crosslinking method. The effect of immoblization conditions on enzyme immoblization efficiency was studied. An activity recovery rate of 86.4% and an enzyme loading of 115.3 mg/g were achieved under the optimal conditions: glutaraldehyde concentration of 1.0%, cross-linking time of 180 min, and the weight ratio of MOF to enzyme of 8:1. The optimal temperature and optimal pH of the immobilized amidase were determined to be 40 °C and 9.0, respectively, and the Km, Vmax and kcat of the immoblized amidase were 58.32 mmol/L, 16.23 µmol/(min·mg), and 1 670 s⁻¹, respectively. The immobilized enzyme was used for (S)-4-fluorophenylglycine synthesis and the optimal reaction conditions were 300 mmol/L of N-phenylacetyl-4-fluorophenylglycine, 10 g/L of immobilized enzyme loading, and reacting for 180 min at pH 9.0 and 40 °C. A conversion rate of 49.9% was achieved under the optimal conditions, and the conversion rate can be increased to 99.9% under the conditions of enantiomeric excess. The immobilized enzyme can be repeatedly used, 95.8% of its original activity can be retained after 20 cycles.


Assuntos
Estruturas Metalorgânicas , Amidoidrolases , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Glicina/análogos & derivados , Concentração de Íons de Hidrogênio , Temperatura
2.
Orv Hetil ; 162(36): 1451-1458, 2021 09 05.
Artigo em Húngaro | MEDLINE | ID: mdl-34482291

RESUMO

Összefoglaló. Bevezetés: A myeloma multiplex mindmáig alapvetoen gyógyíthatatlan betegség, ezért nagy klinikai jelentoségük van az eredményes mento kezeléseknek. A szájon át adható elso proteaszómagátlóval, az ixazomibbal kiegészített lenalidomid-dexametazon terápia jól tolerálható, csak orális szerekbol álló kombináció, mely hazánkban 2015 áprilisától kezdodoen a "Named Patient Program" keretén belül vált elérhetové relabált, refrakter myeloma multiplexes betegek kezelésére. Célkituzés: Kutatásunk célja az ixazomib-lenalidomid-dexametazon kezelés mellett a hosszú távon progressziómentes túlélok célzott vizsgálata. Módszer: A program keretében összesen 7 centrumban 80 visszaeso beteg részesült e triplet kezelésben, adataikat retrospektíven elemeztük. Leíró statisztikai és Kaplan-Meier-analízist végeztünk. Eredmények: A betegek nagyobb hányada reagált: 63,75%-os válaszarány mellett 14 (17,5%) betegnél nem volt terápiás válasz/stabil betegség alakult ki, és 15-nél (18,75%) a betegség a kezelés mellett is progrediált. A progressziómentes túlélés a teljes betegcsoportban 10,6 hónapnak adódott, ugyanakkor 16 beteg (18,75%) két éven túl progressziómentesnek bizonyult, sot közülük 11-nél a betegség még 3 év után sem progrediált. Tanulmányunkban a fenti, hosszú távú túlélo betegcsoport tulajdonságait tárjuk fel. Megbeszélés: A folyamatos terápia a myeloma multiplex kezelésében meghatározóvá vált. Ezért fontos ismernünk, hogy kik lehetnek azok a betegek, akik különösen sokat profitálnak egy bizonyos terápiából. A hosszú távon progressziómentes túlélok között az immunglobulin-nehézláncot érinto transzlokációk vagy triszómiák közül (trend szintjén) az utóbbiak kedvezobb progressziómentes túléléssel bírtak, de progressziómentes platót mindkét betegcsoportban észleltünk. A betegség tumortömegét méro nemzetközi stádiumbeosztás (ISS) nem jelezte elore a hosszú túlélést. Gyógyszerelhagyáshoz vezeto mellékhatást a hosszú távú túlélo csoportban egyet sem regisztráltunk; az észlelt mellékhatások nagy része enyhe volt. Következtetések: Munkánk során az ixazomib-lenalidomid-dexametazon kombinációt effektívnek és biztonságosnak találtuk relabált, refrakter myeloma multiplex kezelésére, mely a betegek mintegy hatodánál több éven át eredményesen alkalmazható. Cikkünkkel a hazai beteganyagon szerzett tapasztalatainkat szeretnénk megosztani a COVID-19-világjárvány alatt különösen aktuálissá vált, tisztán orális terápiás lehetoségrol. Orv Hetil. 2021; 162(36): 1451-1458. INTRODUCTION: Despite great advances in therapy, multiple myeloma is still a largely incurable disease, therefore the importance of salvage therapies is paramount. The first oral proteasome inhibitor ixazomib in combination with lenalidomide-dexamethasone is a tolerable, orally administered regime, which has become available for Hungarian relapsed, refractory multiple myeloma patients from April 2015 in the Named Patient Program. OBJECTIVE: Our goal was to investigate the long-time progression-free surviving patient population treated with the ixazomib-lenalidomide-dexamethasone triplet. METHOD: We retrospectively studied a total of 80 patients from 7 centers who received the triplet combination. Survival analyses were performed. RESULTS: Two-third of the patients responded: the overall response rate was 63.75%. 14 patients (17.5%) did not respond/had stable disease and 15 patients (18.75%) outright progressed upon therapy. Although progression-free survival was only 10.6 months for the entire patient cohort, the disease in a subgroup of 16 patients did not progress within two years. In fact, 11 of them were still in sustained remission after 3 years of therapy. Our goal was to analyze the characteristics of this subgroup. DISCUSSION: The idea of long-term therapy of multiple myeloma is gaining widespread acceptance. Therefore it is important to know which patients may benefit the most from certain therapies. Among these 16 long-term responder patients, reciprocal translocation of the immunoglobulin heavy chain seemed to lack an adverse impact on progression-free survival; comparable to trisomies, both curves had a progression-free plateau. The International Staging System (ISS) score at the start of therapy did not predict long-term survivorship. Most of the side effects in this subgroup were mild, manageable, none led to therapy discontinuation. CONCLUSION: Ixazomib-lenalidomide-dexamethasone was confirmed to be an effective and safe combination for relapsed, refractory multiple myeloma, and one-sixth of the treated patients were able to receive it for several years, effectively. This fully oral therapeutic option is at its best during the present COVID-19 pandemic. Orv Hetil. 2021; 162(36): 1451-1458.


Assuntos
Compostos de Boro/uso terapêutico , Dexametasona/uso terapêutico , Glicina/uso terapêutico , Lenalidomida/uso terapêutico , Mieloma Múltiplo , Glicina/análogos & derivados , Humanos , Mieloma Múltiplo/tratamento farmacológico , Intervalo Livre de Progressão , Estudos Retrospectivos
3.
Water Sci Technol ; 84(5): 1293-1301, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34534124

RESUMO

Glyphosate (GLP) is one of the most widely applied herbicides, and is found ubiquitously in the environment. The removal of glyphosate from waste water and soil is challenging and can be achieved with chemical or biological methods, which, nevertheless, suffer from different disadvantages. The application of a physical plasma for the removal of GLP in water was examined by the application of surface corona discharges in a wire-to-cylinder setup filled with argon. The plasma was ignited at the liquid surface without any additives. By applying a photometric method, GLP was detected after derivatisation with fluorenyl methoxycarbonyl chloride, whereas phosphate was determined with ammonium molybdate. A GLP degradation rate of 90.8% could be achieved within a treatment time of 30 minutes with an estimated energy efficiency of 0.32 g/kWh.


Assuntos
Herbicidas , Poluentes do Solo , Glicina/análogos & derivados , Herbicidas/análise , Águas Residuárias , Água
5.
Einstein (Sao Paulo) ; 19: eAO5657, 2021.
Artigo em Inglês, Português | MEDLINE | ID: mdl-34406313

RESUMO

OBJECTIVE: To evaluate the morphology and morphometry of the muscles extensor digitorium longus and soleus of C57BL/6 females, who were exposed to glyphosate during pregnancy and lactation. METHODS: Twelve female mice from the C57BL/6 lineage were used. After detection of pregnancy, they were divided into a Control Group, which received only water, and a Glyphosate Group, which received water with 0.5% glyphosate during pregnancy and lactation. Both groups received ad libitum standard diet. After weaning, the females were euthanized and weighed; naso-anal length was measured, and fats were collected and weighed. The muscles extensor digitorium longus and soleus were collected, and their length and weight were measured. Then, the muscles were fixed in Methacarn to perform the histological study of muscle fibers. RESULTS: Glyphosate Group presented lower weight gain during pregnancy and also lower final body weight and naso-anal length; however, the other body parameters evaluated did not present a significant difference in relation to the Control Group. Significant differences were also not observed in the analysis of muscle fibers and connective tissue. CONCLUSION: Exposure to 0.5% glyphosate during pregnancy and lactation resulted in lower weight gain during pregnancy, final weight, and naso-anal length. Despite not directly altering the morphology of muscle tissue, these results may indicate enough exposure to interfere with animal metabolism.


Assuntos
Fibras Musculares Esqueléticas , Músculo Esquelético , Animais , Feminino , Glicina/análogos & derivados , Lactação , Camundongos , Camundongos Endogâmicos C57BL , Gravidez
6.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360994

RESUMO

Cholangiocarcinoma is the first most common cancer of the biliary tract. To date, surgical resection is the only potentially curative option, but it is possible only for a limited percentage of patients, and in any case survival rate is quite low. Moreover, cholangiocarcinoma is often chemotherapy-resistant, and the only drug with a significant benefit for patient's survival is Gemcitabine. It is necessary to find new drugs or combination therapies to treat nonresectable cholangiocarcinoma and improve the overall survival rate of patients. In this work, we evaluate in vitro the antitumoral effects of Rigosertib, a multi-kinase inhibitor in clinical development, against cholangiocarcinoma EGI-1 cell lines. Rigosertib impairs EGI-1 cell viability in a dose- and time-dependent manner, reversibility is dose-dependent, and significant morphological and nuclear alterations occur. Moreover, Rigosertib induces the arrest of the cell cycle in the G2/M phase, increases autophagy, and inhibits proteasome, cell migration, and invasion. Lastly, Rigosertib shows to be a stronger radiosensitizer than Gemcitabine and 5-Fluorouracil. In conclusion, Rigosertib could be a potential therapeutic option, alone or in combination with radiations, for nonresectable patients with cholangiocarcinoma.


Assuntos
Antineoplásicos/farmacologia , Neoplasias dos Ductos Biliares/metabolismo , Colangiocarcinoma/metabolismo , Glicina/análogos & derivados , Radiossensibilizantes/farmacologia , Sulfonas/farmacologia , Autofagia/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Fluoruracila/farmacologia , Glicina/farmacologia , Humanos
7.
Environ Pollut ; 286: 117685, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34438504

RESUMO

Microcystin-LR (MC-LR) and glyphosate (GLY) have been classified as a Group 2B and Group 2A carcinogens for humans, respectively, and frequently found in aquatic ecosystems. However, data on the potential hazard of MC-LR and GLY exposure to the fish gut are relatively scarce. In the current study, a subacute toxicity test of zebrafish exposed to MC-LR (35 µg L-1) and GLY (3.5 mg L-1), either alone or in combination was performed for 21 d. The results showed that MC-LR or/and GLY treatment reduced the mRNA levels of tight junction genes (claudin-5, occludin, and zonula occludens-1) and altered the levels of diamine oxidase and D-lactic, indicating increased intestinal permeability in zebrafish. Furthermore, MC-LR and/or GLY treatment remarkably increased the levels of intestinal IL-1ß and IL-8 but decreased the levels of IL-10 and TGF-ß, indicating that MC-LR and/or GLY exposure induced an inflammatory response in the fish gut. MC-LR and/or GLY exposure also activated superoxide dismutase and catalase, generally upregulated the levels of p53, bax, bcl-2, caspase-3, and caspase-9, downregulated the levels of caspase-8 and caused notable histological injury in the fish gut. Moreover, MC-LR and/or GLY exposure also significantly altered the microbial community in the zebrafish gut and the expression of miRNAs (miR-146a, miR-155, miR-16, miR-21, and miR-223). Chronic exposure to MC-LR and/or GLY can induce intestinal damage in zebrafish, and this study is the first to demonstrate an altered gut microbiome and miRNAs in the zebrafish gut after MC-LR and GLY exposure.


Assuntos
Microbioma Gastrointestinal , MicroRNAs , Microbiota , Poluentes Químicos da Água , Animais , Glicina/análogos & derivados , Humanos , Intestinos , Toxinas Marinhas , Microcistinas/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
9.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360925

RESUMO

Mesenchymal stromal cell (MSC) therapy is making its way into clinical practice, accompanied by research into strategies improving their therapeutic potential. Preconditioning MSCs with hypoxia-inducible factors-α (HIFα) stabilizers is an alternative to hypoxic priming, but there remains insufficient data evaluating its transcriptomic effect. Herein, we determined the gene expression profile of 6 human bone marrow-derived MSCs preconditioned for 6 h in 2% O2 (hypoxia) or with 40 µM Vadadustat, compared to control cells and each other. RNA-Sequencing was performed using the Illumina platform, quality control with FastQC and adapter-trimming with BBDUK2. Transcripts were mapped to the Homo_sapiens. GRCh37 genome and converted to relative expression using Salmon. Differentially expressed genes (DEGs) were generated using DESeq2 while functional enrichment was performed in GSEA and g:Profiler. Comparison of hypoxia versus control resulted in 250 DEGs, Vadadustat versus control 1071, and Vadadustat versus hypoxia 1770. The terms enriched in both phenotypes referred mainly to metabolism, in Vadadustat additionally to vesicular transport, chromatin modifications and interaction with extracellular matrix. Compared with hypoxia, Vadadustat upregulated autophagic, phospholipid metabolism, and TLR cascade genes, downregulated those of cytoskeleton and GG-NER pathway and regulated 74 secretory factor genes. Our results provide valuable insight into the transcriptomic effects of these two methods of MSCs preconditioning.


Assuntos
Hipóxia Celular , Expressão Gênica , Glicina/análogos & derivados , Células-Tronco Mesenquimais , Ácidos Picolínicos/farmacologia , Adulto , Células Cultivadas , Feminino , Glicina/farmacologia , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Transcriptoma
10.
An Acad Bras Cienc ; 93(4): e20200233, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34378759

RESUMO

The toxic effects of the insecticides chlorpyrifos and cypermethrin, and the herbicide glyphosate on the growth, biovolume and ultrastructure of the green microalgae Selenastrum capricornutum were evaluated. Concentrations between 9.37-150 mg L-1 of chlorpyrifos, 3.12-100 mg L-1 of cypermethrin and 4.7-60 mg L-1 of glyphosate were assayed along with a control culture. The assayed concentrations were prepared using commercial formulations. After 48 h all tested concentrations of the three pesticides reduced significantly the population growth. The 96 h effective concentration 50 (EC50) was 14.45 mg L-1 for chlorpyrifos, 12.37 mg L-1 for cypermethrin and 15.60 mg L-1 for glyphosate. Cells exposed to the three pesticides showed an increase in the cellular size related to the increase in pesticide concentration and exposure time. The most significant damages observed on the ultrastructure of cells exposed to the three pesticides included thylakoids and mitochondria disruption, formation of electrodense bodies, accumulation of lipids and increase in the size and number of starch granules. The present study demonstrates that the effects of pesticides also extend to non-target organisms having significant ecological implications.


Assuntos
Clorófitas , Clorpirifos , Praguicidas , Piretrinas , Poluentes Químicos da Água , Clorpirifos/toxicidade , Glicina/análogos & derivados , Piretrinas/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
11.
Environ Sci Process Impacts ; 23(7): 1018-1028, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34288996

RESUMO

Glyphosate degradation has been extensively examined; however, only a few detailed computational studies have been performed on the topic so far. There are substantial differences between the degradation products of glyphosate, as AMPA (aminomethylphosphonic acid) is toxic while sarcosine intermediate is non-toxic. These species can have different effects on the environment and, indirectly, on the human body. We performed calculations using density functional theory and post-Hartree-Fock correlated ab initio methods to find the possible mechanisms for the degradation process by small (hydroxyl, peroxyl, and superoxide) radicals. We found that direct sarcosine formation is strongly dependent on the concentration of the radical species. AMPA and glycine were mostly formed as aldehyde derivatives, while in addition to the former, glyoxylate and bicarbonate are formed alternatively. A significant pH effect was also found for the competitive reactions determined by the calculated rate constants of the elementary steps. Overall barriers showed similarities by DFT but ab initio methods could separate them.


Assuntos
Herbicidas , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade , Humanos , Radical Hidroxila , Organofosfonatos
13.
Environ Int ; 156: 106769, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34274860

RESUMO

Since the 1970s, glyphosate has become the most used herbicide of the world. The general population is ubiquitously exposed to glyphosate. Its long-term toxicity, carcinogenic potential and other health effects are controversially discussed. Even though the possible health impacts of glyphosate are of global concern, no population-wide monitoring of glyphosate was done yet. This study presents the worldwide first population-representative data on glyphosate and its metabolite aminomethylphosphonic acid (AMPA) for children and adolescents. 2144 first-morning void urine samples of 3-17-year-old children and adolescents living in Germany were analysed for concentrations of glyphosate and AMPA in the German Environmental Survey for Children and Adolescents 2014-2017 (GerESV). In 52 % of the samples (46 % for AMPA) the urinary glyphosate concentrations were above the limit of quantification of 0.1 µg/L. The geometric mean concentrations were 0.107 µg/L (0.090 µg/gcreatinine) for glyphosate and 0.100 µg/L (0.085 µg/gcreatinine) for AMPA. No clear association between exposure to glyphosate or AMPA and vegetarian diet or consumption of cereals, pulses, or vegetables could be identified. The low quantification rate and the 95th percentiles for glyphosate and AMPA of around 0.5 µg/L demonstrate an overall low exposure of the young population in Germany.


Assuntos
Monitoramento Biológico , Herbicidas , Adolescente , Criança , Pré-Escolar , Monitoramento Ambiental , Alemanha , Glicina/análogos & derivados , Humanos , Organofosfonatos , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico
14.
Sci Total Environ ; 794: 148733, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34217079

RESUMO

Glyphosate application, even in low doses, changes the nutrient composition of crops. The objective of this research was to evaluate the effects of low doses of glyphosate and the sowing season on the macronutrient and micronutrient contents of early cycle common beans. Two experiments were conducted in the field, namely one in the winter season and one in the wet season, using the early cycle common bean cultivar IAC Imperador. The experimental design was a randomized complete block design consisting of the application of low doses of glyphosate [0.0, 1.8, 7.2, 12.0, 36.0, 54.0, and 108.0 g acid equivalent (a.e.) ha-1] in the phenological stage V4 with four replications. Environmental conditions, such as air temperature, interfered with the response of early cycle common beans to low doses of glyphosate. In the winter season, doses of 7.2 g a.e. ha-1 and 36.0 g a.e. ha-1 increased the nutrient composition in the bean leaves, whereas only the Cu content increased in the grains by the dose of 1.8 g a.e. ha-1. In the wet season, there was no increase in the nutrient composition in the bean leaves. The Cu, Zn, Mn, and Fe contents in the grains increased with from the dose of 12 g a.e. ha-1 to above the amount normally observed in common beans, thereby improving the nutritional quality of the food. Our study indicated that low doses of glyphosate alter the nutrient composition of common beans, whereas environmental conditions interfere with the response of common beans to low doses of glyphosate.


Assuntos
Phaseolus , Glicina/análogos & derivados , Glicina/toxicidade , Micronutrientes , Estações do Ano
15.
J Environ Sci (China) ; 106: 66-75, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34210440

RESUMO

Chemical exposure can indirectly affect leaf microbiota communities, but the mechanism driving this phenomenon remains largely unknown. Results revealed that the co-exposure of glyphosate and multi-carbon nanotubes (CNTs) caused a synergistic inhibitory effect on the growth and metabolism of Arabidopsis thaliana shoots. However, only a slight inhibitory effect was induced by nanotubes or glyphosate alone at the tested concentrations. Several intermediate metabolites of nitrogen metabolism and fatty acid synthesis pathways were upregulated under the combined treatment, which increased the amount of energy required to alleviate the disruption caused by the combined treatment. Additionally, compared with the two individual treatments, the glyphosate/nanotube combination treatment induced greater fluctuations in the phyllosphere bacterial community members with low abundance (relative abundance (RA) <1%) at both the family and genus levels, and among these bacteria some plant growth promotion and nutrient supplement related bacteria were markable increased. Strikingly, strong correlations between phyllosphere bacterial diversity and metabolites suggested a potential role of leaf metabolism, particularly nitrogen and carbohydrate metabolism, in restricting the range of leaf microbial taxa. These correlations between phyllosphere bacterial diversity and leaf metabolism will improve our understanding of plant-microbe interactions and the extent of their drivers of variation and the underlying causes of variability in bacterial community composition.


Assuntos
Arabidopsis , Microbiota , Nanotubos de Carbono , Glicina/análogos & derivados , Folhas de Planta
16.
J Environ Sci Health B ; 56(7): 658-669, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34218722

RESUMO

Glyphosate is a broad-spectrum herbicide that has been widely used for nonselective weed control in soybean fields. In the present study, RNA-seq of an Fusarium verticillioides isolate exhibiting resistance to 120 mM glyphosate revealed gene expression occurring in the presence of glyphosate and led to the identification and screening of candidate genes. A transcriptome analysis revealed 5,548 and 5,361 differentially expressed genes (DEGs) in the glyphosate resistant (GR) Fusarium verticillioides isolate treated with 45 and 90 mM glyphosate, respectively. The gene ontology (GO) pathways associated with these differentially expressed genes primarily included metabolic process, amine metabolic process, cellular aromatic compound metabolism and stress response. The primary Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathways included biosynthesis of secondary metabolites, carbon metabolism, glycolysis/gluconeogenesis, and nitrogen metabolism. The glyphosate degradation-related gene fv04, which belongs to the 3-isopropylalate dehydratase of the aconitase superfamily, was cloned to generate the prokaryotic expression vector pET-29b-fv04, which could be stably expressed in E. coli and promote the degradation of 52.3% of 500 mg/L glyphosate in 72 h. The results of the present study provide new ideas and insights for the acquisition of glyphosate resistance resources.


Assuntos
Fusarium , Escherichia coli , Fusarium/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glicina/análogos & derivados
17.
Biosens Bioelectron ; 191: 113434, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34225056

RESUMO

An electrochemical sensor based on molecularly imprinted polypyrrole nanotubes (MIPNs) has been developed for the detection of glyphosate (Gly) with high sensitivity and specificity. Herein, the MIPNs are prepared by imprinting Gly sites on the surface of polypyrrole (PPy) nanotubes. The synthesized MIPNs have high electrical conductivity and exhibit rapid adsorption rate, enhanced affinity and specificity to Gly. An electrochemical sensor for Gly detection is fabricated by assembling MIPNs-modified screen-printed electrodes with a 3D-printed electrode holder, which is highly portable and suitable for real-time detection. The results demonstrate that the MIPNs-based electrochemical sensor for Gly exhibits a wide detection range of 2.5-350 ng/mL with a limit of detection (LOD) of 1.94 ng/mL. Besides, the Gly sensor possessed good stability, reproducibility, and excellent selectivity against other interferents. The practicability of the sensor is verified by detecting Gly in orange juice and rice beverages, indicating that the sensor is suitable for monitoring pesticides in actual food and environmental samples.


Assuntos
Técnicas Biossensoriais , Impressão Molecular , Nanotubos de Carbono , Técnicas Eletroquímicas , Eletrodos , Glicina/análogos & derivados , Limite de Detecção , Polímeros , Pirróis , Reprodutibilidade dos Testes
18.
Toxicology ; 459: 152851, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34246717

RESUMO

Glyphosate (G) is the active ingredient of the most widely used herbicide products. It targets the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), which lacks in humans, suggesting to confer a low mammalian toxicity to G-based herbicides (GBHs). Despite this, the use of G is currently under intense debate. Many studies indicating its hazard and toxicity on non-target organisms are emerging, and associations between GBHs and immune-endocrine disturbances have been described. This review aims to investigate, based on recent epidemiological studies and studies performed in vitro and in vivo in animals, the possible association between GBHs and immune-endocrine alterations. Published data suggest that GBHs have endocrine disrupting potentiality targeting sex and thyroid hormones, although its relevance for humans will require further investigations. Evidence of immunotoxicity are limited compared to those on endocrine effects, but overall highlight possible noxious effects, including lung inflammation and rhinitis. An attractive hypothesis could be the one that connects microbiota dysbiosis with possible immune-endocrine outcomes. Indeed, several intestinal microorganisms express the enzyme EPSPS and, studies are emerging that highlight a possible G-induced dysbiosis. Considering the wide use of GBHs in agriculture, further studies investigating their noxious effects at levels relevant for human exposure should be performed. A critical analysis of emerging evidence of G toxicity is required to better characterize its safety profile. In addition, attention should be paid to the differences between G alone and its formulations, which, containing substances able to increase G absorption, may present a different toxicity profile.


Assuntos
Disruptores Endócrinos , Glicina/análogos & derivados , Herbicidas/efeitos adversos , Sistema Imunitário/efeitos dos fármacos , Animais , Glicina/efeitos adversos , Humanos , Microbiota/efeitos dos fármacos
19.
ACS Sens ; 6(7): 2738-2746, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34255489

RESUMO

Glyphosate (GLY) is a broad-spectrum herbicide and is the most used pesticide worldwide. This vast usage has raised strong interest in the ecotoxicological impacts and human risks, with contamination of water being a major concern. Decentralized analytical techniques for water monitoring are of high importance. In this work, we present a small, low-cost, and time-effective electrochemical, chip-based microfluidic device for direct electrochemical detection of GLY downstream of a molecularly imprinted polymer (MIP) concentrator. We studied the electrochemical behavior of GLY and its metabolite aminomethylphosphonic acid (AMPA) using cyclic voltammetry with noble metal electrodes in acidic, neutral, and basic media. A chronoamperometric sensor protocol was developed for sensitive and selective GLY measurements on gold electrodes. The optimized protocol was transferred to a chip-based microsensor platform for online and real-time detection of GLY in a microfluidic setup. The results in the range from 0 to 50 µM GLY in 0.5 M H2SO4 show high linearity and a sensitivity of 10.3 ± 0.6 µA mm-2 mM-1 for the chip-based microfluidic platform. Successful recovery of GLY concentrated from untreated tap water and its precise detection from low volumes demonstrates the advantages of our system.


Assuntos
Impressão Molecular , Glicina/análogos & derivados , Humanos , Microfluídica , Polímeros Molecularmente Impressos , Organofosfonatos , Água
20.
J Agric Food Chem ; 69(28): 7969-7978, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34232658

RESUMO

The tea shrub is grown in long-standing orchards, an environment that is suitable for persistent weed growth, which is increasingly controlled by herbicides. Therefore, there is increasing concern that tea consumers may be exposed to herbicide residues. In this study, the levels of glufosinate-ammonium (GLU), glyphosate [N-(phosphonomethyl) glycine; PMG], and its metabolite aminomethyl phosphoric acid (AMPA) were determined in tea samples by HPLC-MS/MS using several current purification methods and a new method that we developed herein. The matrix effect of our proposed method was between -27.3 and 27.7%, which was lower than that in other methods, indicating that this method effectively reduced the interference of tea matrix in the mass spectrometry process. This method was used to determine the levels of PMG, GLU, and AMPA in 780 samples, including six traditional Chinese teas (green tea, black tea, oolong tea, dark tea, white tea, and yellow tea) and a floral tea, from 14 provinces of China. Probability estimates showed that the 95th percentile risk entropy values of the three pesticide residues were far below the acceptable risk level. The risk assessment results showed that exposure to PMG, GLU, and AMPA caused by drinking tea beverages poses no significant risk to human health.


Assuntos
Herbicidas , Espectrometria de Massas em Tandem , Aminobutiratos , China , Cromatografia Líquida de Alta Pressão , Glicina/análogos & derivados , Herbicidas/análise , Humanos , Ácidos Fosfóricos , Medição de Risco , Chá
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