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1.
Appl Opt ; 60(21): 6097-6102, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34613273

RESUMO

Laser frequency stabilization plays an important role in high-precision spectroscopic measurements. Since high-accuracy commercial wavemeters became available, wavemeter-based frequency stabilization has found a broad application due to its convenience, flexibility, and wide applicability. However, such stabilization schemes frequently suffer from long-term drift, since the accuracy of the wavelength measurement of a wavemeter is affected by ambient temperature fluctuation. In this work, we demonstrate that such long-term drift can be suppressed by regularly calibrating the frequency of a wavemeter-locked laser utilizing an optical frequency comb, which has much better long-term stability. Under this dual-referenced locking scheme, the Allan deviation is reduced to 3.5 E-12 at 4000 s for a fiber laser operated at 548 nm, which when used in the optical Ramsey spectroscopic measurement of 7Li+, reduces the standard deviation by as much as 40%, compared to the case when only wavemeter locking is applied.

2.
Adv Mater ; : e2007778, 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34510563

RESUMO

Cancer has been one of the most common life-threatening diseases for a long time. Traditional cancer therapies such as surgery, chemotherapy (CT), and radiotherapy (RT) have limited effects due to drug resistance, unsatisfactory treatment efficiency, and side effects. In recent years, photodynamic therapy (PDT), photothermal therapy (PTT), and chemodynamic therapy (CDT) have been utilized for cancer treatment owing to their high selectivity, minor resistance, and minimal toxicity. Accumulating evidence has demonstrated that selective delivery of drugs to specific subcellular organelles can significantly enhance the efficiency of cancer therapy. Mitochondria-targeting therapeutic strategies are promising for cancer therapy, which is attributed to the essential role of mitochondria in the regulation of cancer cell apoptosis, metabolism, and more vulnerable to hyperthermia and oxidative damage. Herein, the rational design, functionalization, and applications of diverse mitochondria-targeting units, involving organic phosphine/sulfur salts, quaternary ammonium (QA) salts, peptides, transition-metal complexes, guanidinium or bisguanidinium, as well as mitochondria-targeting cancer therapies including PDT, PTT, CDT, and others are summarized. This review aims to furnish researchers with deep insights and hints in the design and applications of novel mitochondria-targeting agents for cancer therapy.

3.
J Clin Anesth ; 75: 110504, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34509960

RESUMO

STUDY OBJECTIVE: To evaluate the impact of intensive glucose control on diabetic patients undergoing surgery. DESIGN: A systematic review and meta-analysis of randomized controlled trials. PubMed, CENTRAL, EMBASE, ISI Web of Science, and CINAHL databases were searched from inception to 13 December 2020. SETTING: Operating room, postoperative recovery area and ward, up to 30 days after surgery. PATIENTS: Diabetic patients undergoing surgery. INTERVENTIONS: We used Review Manager 5.4 to pool the data with a random-effects model. The quality of evidence was rated using the Grading of Recommendations, Assessment, Development and Evaluation system. MEASUREMENTS: The primary outcomes were infectious complications, postoperative mortality, and hypoglycaemia. The secondary outcomes included atrial fibrillation, myocardial infarction, stroke, delirium, renal failure, postoperative mechanical ventilation time, length of intensive care unit (ICU) stay, and hospital stay. MAIN RESULTS: Thirteen studies involving 1582 participants were included. Compared with conventional glucose control, intensive glucose control was associated with a lower risk of infectious complications (risk ratio [RR], 0.35; 95% confidence interval [CI], 0.19-0.63; low-quality evidence), atrial fibrillation (RR, 0.55; 95% CI, 0.42-0.71; high-quality evidence), and renal failure (RR, 0.38; 95% CI, 0.15-0.95; moderate-quality evidence), as well as a shorter length of stay in the ICU (mean difference (MD), -0.55 day; 95% CI, -1.05 to -0.05 days; very-low-quality evidence) and hospital (MD, -1.61 days; 95% CI, -2.78 to -0.44 days; very-low-quality evidence). However, intensive glucose control was associated with a higher risk of hypoglycaemia (RR, 3.00; 95% CI, 1.97-4.55; high-quality evidence). There were no significant differences in postoperative mortality, myocardial infarction, stroke, delirium, or postoperative mechanical ventilation time. CONCLUSIONS: Intensive glucose control in diabetic patients is associated with a reduction in some adverse postoperative outcomes including infectious complications, but also appears to increase the risk of hypoglycaemia. Further well-designed studies may be needed to determine appropriate regimens to reduce hypoglycaemia incidence. PROSPERO REGISTRATION NUMBER: CRD42021226138.

4.
J Agric Food Chem ; 69(38): 11154-11162, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34529438

RESUMO

In this study, the enantioselective activity of the chiral fungicide triticonazole (TRZ) against target pathogens of seed-borne diseases and the effect on the early phenotypic indexes and physiological and biochemical indexes of wheat following the soaking of seeds were studied. S-TRZ had low fungicidal activity and significantly inhibited the germination of wheat seeds. Seedlings in the S-TRZ treatment group suffered severe oxidative damage; the contents of glutathione (GSH) and malondialdehyde (MDA) were significantly increased. S-TRZ significantly inhibited the synthesis of gibberellin (GA) and ethylene (ETH), while it significantly increased that of jasmonic acid (JA). R-TRZ showed the highest activity against two smut fungi; the treatment of seeds with 5 g (ai)/100 kg R-TRZ had little influence on early wheat growth. The plant hormones were synthesized normally; seedlings grew well, and the fresh weight increased significantly following this treatment. Based on these data, we propose to develop and apply R-TRZ using the national recommended doses to control seed-borne diseases of wheat.


Assuntos
Praguicidas , Triticum , Ciclopentanos , Germinação , Plântula , Sementes , Estereoisomerismo , Triazóis/toxicidade
5.
J Hazard Mater ; 416: 125911, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492845

RESUMO

Plant growth can be influenced by the application of triazole pesticides as these regulate physiological processes such as plant hormonal levels and enzyme activity. Homology modeling and molecular docking studies suggested that inhibition of ADP-glucose pyrophosphorylase activity in two trans-stereoisomers treatments hinders starch accumulation during the grain filling stage. A field experiment investigated the effects of metconazole racemate, cis-1R,5S-stereostereoisomer, and cis-1S,5R-stereoisomer application at the flowering stage on wheat grain ripening and yield. The concentrations of racemate and both cis-stereoisomers were detected in wheat plant and grain samples. Compared with the racemate, both cis-stereoisomers were more persistent in the matrices. Treatment with cis-1R,5S-stereoisomer decreased grain weight and yield of wheat by delaying chlorophyll degradation, increasing the ethylene content, and decreasing the level of abscisic acid. The germination of harvested seeds was adversely affected by racemate treatment as a result of gibberellin and abscisic acid metabolism regulation and the transcription of signaling-related genes. Therefore, cis-1S,5R-stereoisomer was recommended to be used as metconazole pesticide at the flowering stage.


Assuntos
Praguicidas , Triticum , Germinação , Simulação de Acoplamento Molecular , Sementes , Triazóis
6.
J Agric Food Chem ; 69(35): 10281-10291, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34432462

RESUMO

Food wastage represented by the deterioration of perishable food like fruits and vegetables is a serious global problem with tremendous ethical, financial, and environmental costs. The atmosphere (CO2 and O2) has a crucial role in food storage and can regulate physiological food metabolism and microbial growth. Modified atmosphere packaging (MAP) is a promising method used to extend shelf life and preserve the quality of perishable food; yet, its use depends on the specific gas permeability and selectivity of polymer membranes to generate an atmosphere desirable for storage. In this study, we established and validated a new plant leaf-mimetic shellac-based MAP membrane embedded with chitosan porous microspheres loaded with antimicrobial tannic acid (TA-CPM) as gas "switches" for regulating O2 and CO2 permeability and CO2/O2 selectivity. The effects of different amounts of TA-CPM added into the hybrid membranes were examined for litchi preservation at room temperature. Our results showed that this hybrid TA-CPM/shellac packaging membrane could regulate the internal CO2 and O2 concentrations and the CO2/O2 ratio within the packages containing litchis by adjusting the addition amount of TA-CPM. The 0.05% TA-CPM/shellac and 0.10% TA-CPM/shellac packages, especially 0.05% TA-CPM/shellac, generated a more desirable CO2 and O2 atmosphere for litchi preservation compared with controls, which was reflected by the delaying of browning and rotting, maintaining of the natural color of the litchi pericarp, preservation of pulp quality, inhibition of polyphenol oxidase and guaiacol peroxidase activities, and reduction of oxidative cell damage in litchis. The results suggested that 0.05% TA-CPM/shellac and 0.10% TA-CPM/shellac packaging membranes, especially 0.05% TA-CPM/shellac, could generate an ideal atmosphere for litchi storage at room temperature, demonstrating that this permeation-controlled hybrid membrane has great potential in food preservation and other applications requiring a modified atmosphere.


Assuntos
Litchi , Atmosfera , Microbiologia de Alimentos , Embalagem de Alimentos , Conservação de Alimentos , Frutas , Microesferas , Oxigênio , Porosidade
7.
Pest Manag Sci ; 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34432938

RESUMO

BACKGROUND: Soil fumigants-the most effective agrochemicals for managing soil-borne diseases-have been used extensively. However, high volatility, moderate toxicity and insufficient effective duration considerably limit their application. In the present study, interface polymerization was used to combine modified biochar (BC) and polyurea microcapsules (MCs) to co-encapsulate allyl isothiocyanate (AITC), developing a model fumigant for controlled release (AITC@BC-MCs). RESULTS: The physical characteristics of BC modified by sand-milling were significantly improved. In addition, chemical properties and morphological features of AITC@BC-MCs characterized by integrated methods revealed successful preparation of BC-MCs. Compared with monolayer MCs, BC-MCs could significantly delay AITC release owing to the composite obstruction effect. Moreover, modifying BC endowed the cargo molecules with a pH-responsive release property. Additionally, this composite showed a longer persistent duration by prolonging AITC degradation half-life, which was 3.2-3.5-fold greater than that of the AITC technical concentrate under different soil conditions. Finally, the control efficacy of the AITC@BC-MC against pathogens, including nematodes and fungi, as well as against weeds was significantly enhanced at the same dose, but the composite did not inhibit seed germination and growth after 10 days when fumigated soil was aerated. CONCLUSION: Construction of a composite encapsulation system enhanced pesticide efficacy, reduced dose via controlled release and delayed fumigant degradation in soil, indicating the great potential of this strategy for developing an effective and environmentally friendly fumigant formulation.

8.
Sci Rep ; 11(1): 16409, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385484

RESUMO

We recently showed that NOTUM, a liver-secreted Wnt inhibitor, can acutely promote browning of white adipose. We now report studies of chronic overexpression of NOTUM in liver indicating that it protects against diet-induced obesity and improves glucose homeostasis in mice. Adeno-associated virus (AAV) vectors were used to overexpress GFP or mouse Notum in the livers of male C57BL/6J mice and the mice were fed an obesifying diet. After 14 weeks of high fat, high sucrose diet feeding, the AAV-Notum mice exhibited decreased obesity and improved glucose tolerance compared to the AAV-GFP mice. Gene expression and immunoblotting analysis of the inguinal fat and brown fat revealed increased expression of beige/brown adipocyte markers in the AAV-Notum group, suggesting enhanced thermogenic capacity by NOTUM. A ß3 adrenergic receptor agonist-stimulated lipolysis test suggested increased lipolysis capacity by NOTUM. The levels of collagen and C-C motif chemokine ligand 2 (CCL2) in the epididymal white adipose tissue of the AAV-Notum mice were significantly reduced, suggesting decreased fibrosis and inflammation, respectively. RNA sequencing analysis of inguinal white adipose of 4-week chow diet-fed mice revealed a highly significant enrichment of extracellular matrix (ECM) functional cluster among the down-regulated genes in the AAV-Notum group, suggesting a potential mechanism contributing to improved glucose homeostasis. Our in vitro studies demonstrated that recombinant human NOTUM protein blocked the inhibitory effects of WNT3A on brown adipocyte differentiation. Furthermore, NOTUM attenuated WNT3A's effects on upregulation of TGF-ß signaling and its downstream targets. Overall, our data suggest that NOTUM modulates adipose tissue function by promoting thermogenic capacity and inhibiting fibrosis through inhibition of Wnt signaling.

9.
Artigo em Inglês | MEDLINE | ID: mdl-34217650

RESUMO

This study evaluated the efficacy of botulinum toxin A (BTX A) in improving the aesthetic appearance of lips. Twenty-four outpatients with clinical evidence indicating decreased fullness of lips or gummy smile were selected and received BTX A injection on the orbicularis oris. We observed a significant decrease in wrinkles and improvement in gummy smile in all patients 4 weeks after the injection. Aesthetic lines also changed significantly. Local injection of BTX A on the orbicularis oris could simultaneously achieve mild lip enhancement, improvement in fine wrinkles around lips, and mild gummy smile.

10.
J Hazard Mater ; 418: 126277, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118542

RESUMO

Labels or tapes are widely used on fresh fruits and vegetables, which may contain phthalates (PAEs). There are few studies on the contamination pathway of PAEs from labels or tapes to food stuff. In this study, the concentrations of eleven PAEs in adhesive labels, tapes, labeled fruits and vegetables on the market were investigated. The eleven PAEs were detected with the total concentration of 7.44-30.51 mg/m2 in labels and tapes. Diethyl phthalate (DEP), di-n-butyl phthalate (DIBP), dimethyl phthalate (DMP), Bis (2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) had the highest detection frequency in adhesive material samples. The concentrations of PAEs in labeled fruits were higher than that in unlabeled fruits, especially in the peel, indicating PAEs could transfer from labels or tapes to fruits and vegetables. Furthermore, the migration behaviors of PAEs from labels or tapes to apples, avocados and celery were investigated. It was found that the PAEs could penetrate to apple and avocado pulp through the peel, resulting in the residue of the PAEs in the whole fruit. Unlike apple peel, the thick avocado peel was more difficultly penetrated by the PAEs. Due to the high lipid content, the PAEs distributed more evenly in avocado pulp than in apple pulp. The migrations up to a maximum of 4.16 mg/kg were found for butyl benzyl phthalate (BBP) in avocado peel and up to a maximum of 0.188 mg/kg in avocado pulp. The average migration of the PAEs in celery ranged from 0.3 to 26.1 µg/kg in three days and the low migration might result from the rough surface and less contacting area. These findings suggest that the use of labels or tapes in direct contact may increase the risk of PAEs exposure to humans through fruits and vegetables.


Assuntos
Ácidos Ftálicos , Verduras , China , Dibutilftalato , Ésteres/análise , Frutas/química , Humanos , Ácidos Ftálicos/análise
11.
J Hazard Mater ; 418: 126100, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34098260

RESUMO

Bisphenols (BPs), as widely used plastic additives, penetrate into our daily lives. BPs are considered endocrine disruptors and could potentially induce obesity. In this study, the effects of bisphenol A (BPA) and tetrabromobisphenol A (TBBPA) on food intake and lipid metabolism in zebrafish were determined. Moreover, the impact of BPA and TBBPA on the endocannabinoid system (ECS) of zebrafish was further explored by metabolomics, transcriptomics, and molecular docking analysis. Here we show that exposure to BPA and TBBPA at concentrations commonly found in the environment (20, 100, and 500 µg/L) led to hyperphagia and obesity in adult male zebrafish. Metabolomics and histopathological analysis revealed significant lipid accumulation in the liver of zebrafish exposed to BPA and TBBPA. The expression of ECS-related genes, in conjunction with RNA-Seq results, further indicated that BPA and TBBPA increased appetite and induced obesity by activating cannabinoid receptor type 1(CB1). Furthermore, molecular docking revealed that six representative BPs including BPA and TBBPA could bind to the CB1 receptor. Collectively, these findings indicate that CB1 may be a potential target for BPs to induce obesity.


Assuntos
Disruptores Endócrinos , Peixe-Zebra , Animais , Compostos Benzidrílicos , Masculino , Simulação de Acoplamento Molecular , Obesidade/induzido quimicamente , Obesidade/genética , Fenóis , Receptor CB1 de Canabinoide/genética , Peixe-Zebra/genética
12.
J Food Sci ; 86(7): 2910-2923, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34147039

RESUMO

The effect of pine needle extract from Cedrus deodara (PNE) on the quality of salted meat was reported, and its action mechanism was further investigated. With the treatment of PNE, the physicochemical properties of salted meat were improved. The peroxide value decreased from 16.18 to 6.78 mmol O2 /kg, while the thiobarbituric acid value decreased from 0.79 to 0.40 mg MDA/kg. Moreover, the salted meat with PNE also had the better texture, color, and volatile compositions. The 0.2% PNE group showed the highest ΔE value (63.16 ± 0.56), hardness (813.5 ± 48.7 g), and volatility (45.86 ± 0.39), while the control group showed the lowest ΔE value (43.92 ± 2.13), hardness (515.8 ± 17.3 g) and volatility (29.97 ± 0.56). In addition, with the analysis of fluorescence and circular dichroism spectroscopy, the spatial structures of myofibrillar protein (MP) in salted meat were obviously changed by PNE. Meanwhile, methylconiferin, 1-O-feruloyl-ß-D-glucose, nortrachelogenin, secoxyloganin, 1-O-(4-coumaroyl)-ß-D-glucose and pelargonidin-3-O-glucoside were identified from PNE. Furthermore, according to the analysis of molecular docking, hydrogen bond, hydrophobic force, and electrostatic force were obtained as the main molecular forces between MP and the phenolic compounds of PNE, while arginine, glutamic acid, and glycine residues were the main binding sites. All results suggested that PNE might be a potential candidate to improve the quality of salted meat in the food industry. PRACTICAL APPLICATION: The quality deterioration of meat may not only affect its further processing and consumption but also may lead to some food safety problems. In present study, PNE exhibited the fine capability to inhibit the oxidation of meat, while it could ameliorate the texture, color, and physicochemical properties of meat due to its tightly interaction with myofibrillar protein. All result suggested that PNE could be potentially utilized to improve the quality of meat in food industry.


Assuntos
Cedrus/química , Conservantes de Alimentos/farmacologia , Qualidade dos Alimentos , Carne/análise , Extratos Vegetais/farmacologia , Sensação , Cloreto de Sódio/química , Animais , Conservantes de Alimentos/química , Humanos , Simulação de Acoplamento Molecular , Extratos Vegetais/química
13.
Comput Intell Neurosci ; 2021: 8865816, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113377

RESUMO

An accurate prediction of stock market index is important for investors to reduce financial risk. Although quite a number of deep learning methods have been developed for the stock prediction, some fundamental problems, such as weak generalization ability and overfitting in training, need to be solved. In this paper, a new deep learning model named Random Long Short-Term Memory (RLSTM) is proposed to get a better predicting result. RLSTM includes prediction module, prevention module, and three full connection layers. Input of the prediction module is a stock or an index which needs to be predicted. That of the prevention module is a random number series. With the index of Shanghai Securities Composite Index (SSEC) and Standard & Poor's 500 (S&P500), simulations show that the proposed RLSTM can mitigate the overfitting and outperform others in accuracy of prediction.


Assuntos
Investimentos em Saúde , Memória de Longo Prazo , China
14.
Plant Dis ; 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34132596

RESUMO

Maize rough dwarf disease (MRDD), caused by a virus, seriously affects maize quality and yield worldwide. MRDD can be most effectively controlled with disease-resistant hybrids of corn. Here, MRDD-resistant (Qi319) and -susceptible (Ye478) parental inbred maize lines and their 314 recombinant inbred lines (RILs) that were derived from a cross between them were evaluated across three environments. A stable resistance QTL, qMrdd2, was identified and mapped using BLUP values to a 0.55 Mb region between the markers MK807 and MK811 on chromosome 2 (B73 RefGen_v3), which was found to explain 8.6 to 11.0% of the total phenotypic variance in MRDD resistance. We validated the effect of qMrdd2 using a chromosome segment substitution line (CSSL) that was derived from a cross between maize inbred Qi319 as the MRDD resistance donor and Ye478 as the recipient. Disease severity index of the CSSL haplotype II harboring qMrdd2 was significantly lower than that of the susceptible parent Ye478. Subsequently, we fine-mapped qMrdd2 to a 315 kb region flanked by the markers RD81 and RD87 by testing recombinant-derived progeny using selfed backcrossed families. In this study, we identified a novel QTL for MRDD-resistance by combining the RIL and CSSL populations, which can be used to breed for MRDD resistant varieties of maize. Keywords: Maize, Maize rough dwarf disease, QTL, Fine-mapping, Recombinant inbred line, Chromosome segment substitution line.

15.
BMC Anesthesiol ; 21(1): 144, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980156

RESUMO

BACKGROUND: Nebulized lidocaine reduced stress response for endotracheal intubation. However, the impact of novel lidocaine aerosol inhalation for intubation by ultrasonic atomizer was unclear. Hence, we designed aerosol inhalation of lidocaine by ultrasonic atomizer, to seek whether the dosage of sufentanil for intubation could be less or not. METHODS: Intravenous injection of sufentanil started at 0.5 µg/kg, and sufentanil dosage was increased/decreased (step-size 0.05 µg/kg for sufentanil) using Dixon's up and down method. The observation was terminated after 8 reflexes. RESULTS: The EC50 and EC95 of sufentanil with lidocaine by ultrasonic atomizer for intubation were found to be 0.232 µg/kg (95% CI: 0.187-0.270 µg/kg) and 0.447 µg/kg (95% CI: 0.364-0.703 µg/kg). 55.88% out of 34 patients showed hemodynamic index change < 20% of baseline during intubation. CONCLUSION: Aerosol inhalation of lidocaine by ultrasonic atomizer reduced the dosage of sufentanil for endotracheal intubation. Lidocaine inhalation by ultrasonic atomizer for airway anesthesia with minimal dosage of sufentanil could be recommended, particularly in patients who need more stable hemodynamic changes or spontaneous respiration. TRIAL REGISTRATION: Chinese Registry of Central Trial, ChiCTR-IOR-17014198 . Registered 28 December 2017.

16.
Ecotoxicol Environ Saf ; 219: 112236, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33989919

RESUMO

After application, pesticides remained in the field may contaminate water resources through surface runoff and leaching, posing a threat to aquatic ecosystem. In the current study, the accumulation, translocation, distribution and removal of four triazine pesticides (simazine, atrazine, terbuthylazine and metribuzin) by free floating aquatic plant Eichhornia crassipes (E. crassipes) in water-sediment microcosm were investigated and the removal mechanisms were explored. E. crassipes was exposed to an initial concentration of 50 µg·L-1 and the pesticide levels in water, sediment, roots and shoots of E. crassipes were monitored during 30 days. The results demonstrated that E. crassipes was capable of accumulating triazine pesticides with the bio-concentration factor (BCF) ranging from 0.8 to 18.4. Triazine pesticides were mainly stored in roots, and root accumulation and translocation amount depend on the hydrophobicity of the pesticides. The removal of the pesticides in water were significantly accelerated by the presence of E. crassipes, with the removal efficiency ranging from 66% to 79% after 30 days of treatment. Though phytoaccumulation only constituted 2-18% of the total spiked pesticides in the microcosm, E. crassipes played a vital role in removing simazine, atrazine and metribuzin. However, microbial degradation in sediment was the main pathway for the removal of terbuthylazine in the microcosm. This study demonstrated the potential application of E. crassipes to accelerate removal of contaminants from aquatic environment.


Assuntos
Eichhornia/metabolismo , Praguicidas/metabolismo , Poluentes Químicos da Água/metabolismo , Atrazina/metabolismo , Biodegradação Ambiental , Ecossistema , Praguicidas/análise , Triazinas/metabolismo , Água/metabolismo , Poluentes Químicos da Água/análise
17.
ACS Nano ; 15(5): 8742-8752, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-33970594

RESUMO

About one-third of the world's food is lost and wasted each year, along with excessive carbon emission, disposals, and other environmental issues. The rotting of perishable products like fruits and vegetables accounts for the largest percentage of food waste due to their short shelf life. The storage atmosphere (H2O, O2, CO2) acts as a key role in the preservation process and could regulate plants' physiological metabolism and microbial growth. In this work, a facile and biomimetic strategy is introduced for food preservation at room temperature employing PLLA (poly(l-lactic acid)) or chitosan porous microspheres as gas "switches" or "stomata" in a shellac membrane to regulate O2, CO2, and H2O permeability and CO2/O2 selectivity. Surface coatings on fruits or packaging films prepared through this strategy show exceptional preservation performance on five selected model fruits with different respiratory metabolisms. These hybrid materials could effectively control the gases (O2, CO2, and H2O) permeability and CO2/O2 selectivity by adding different amounts of porous microspheres or depositing small functional molecules, which demonstrate excellent antioxidant, antimicrobial, water-resistant, and reusable properties. This gas permeation control strategy has great potential in food preservation as well as other applications where a controlled atmosphere is required.


Assuntos
Embalagem de Alimentos , Eliminação de Resíduos , Biomimética , Gases , Folhas de Planta
18.
Environ Sci Pollut Res Int ; 28(34): 47099-47106, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33884551

RESUMO

Heavy metals may coexist with pesticides in farmland through wastewater irrigation, application of pesticides and chemical fertilizers, or unappropriated waste disposal. Heavy metals are toxic to soil microorganism, which may influence the environmental behavior of pesticides subsequently. In this study, the influence of Cd2+ and Pb2+ on the degradation of α-cypermethrin and its metabolites, 3-phenoxphenoxybenzoic acid (3-PBA) and 3-(2',2'-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (DCCA), were investigated through soil incubation experiment. It was found heavy metals like Cd2+ and Pb2+ will inhibit the degradation of α-cypermethrin, especially at high concentrations. Pb2+ has a stronger inhibitory effect on the degradation of α-cypermethrin than Cd2+ in the same concentration. With the presence of 10 mg/kg Pb2+, the half-life of α-cypermethrin increased from 41.1 to 99.9 days, even the half-life was 129.3 days with 50 mg/kg of Pb2+. Besides, heavy metals influenced the chiral selective degradation of α-cypermethrin. The enantiomer fraction was near 0.5 when 10 mg/kg of heavy metals existed. Furthermore, the adverse effects of heavy metals on soil urease, catalase, and sucrase activity were assayed. In tested concentrations (10 and 50 mg kg-1), the heavy metals result in strong inhibition of the activity of the enzymes present on soil, jeopardizing the biodegradation by the microbiome and which may inhibit the degradation of α-cypermethrin.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio , Chumbo , Metais Pesados/análise , Piretrinas , Solo , Poluentes do Solo/análise , Estereoisomerismo
19.
Environ Sci Pollut Res Int ; 28(32): 43476-43482, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33834344

RESUMO

PEN is a widely used triazole fungicide, usually used to control grape white rot. In the process of agricultural use, PEN will be scattered to the soil and water environment, which brings certain environmental safety risks. In this study, we used a 200-µg/L solution of Rac-PEN, (+)-PEN, and (-)-PEN to perform a 28-day exposure test on zebrafish. The results showed that long-term low-dose PEN exposure did not significantly change the growth factor K and the number of spawning of zebrafish. However, the content of four important hormones vitellogenin, 17ß-estradiol, testosterone, and 11-ketotestosterone in zebrafish has changed significantly. Furthermore, we measured the expression of hypothalamus-pituitary-gonads-liver (HPGL) axis-related genes, and the results showed that the expressions of related genes in the brain, gonads, and liver all changed significantly. Combining the above results, we can conclude that PEN has obvious endocrine disrupting effect on zebrafish, and has gender-specific endocrine effects. Meanwhile, Rac-PEN and (+)-PEN had stronger effects on the endocrine system of zebrafish than (-)-PEN.


Assuntos
Disruptores Endócrinos , Poluentes Químicos da Água , Animais , Disruptores Endócrinos/toxicidade , Gônadas , Triazóis/toxicidade , Vitelogeninas/genética , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
20.
Sci Total Environ ; 784: 147194, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-33901949

RESUMO

In this study, the stereochemistry, stereoselective fungicidal bioactivity, and antifungal mechanism of chiral triazole fungicide metconazole were investigated. The configurations of metconazole stereoisomers were determined to be (1R, 5R)-metconazole, (1R, 5S)-metconazole, (1S, 5S)-metconazole, and (1S, 5R)-metconazole through using electronic circular dichroism spectroscopy. The bioactivities of four stereoisomers and their stereoisomer mixture toward Fusarium graminearum Schw and Alternaria triticina were found to be in the following order: (1S, 5R)-metconazole > the stereoisomer mixture > (1S, 5S)-metconazole > (1R, 5R)-metconazole > (1R, 5S)-metconazole. In addition, the fungicidal activities of (1S, 5R)-metconazole against two tested pathogens was 13.9-23.4 times higher than those of (1R, 5S)-metconazole. Molecular docking methodology was applied to characterize the docking energy and distances between Cytochrome P450 CYP51B and the metconazole stereoisomers, and (1S, 5R)-metconazole showed the strongest binding energy and the shortest distance binding to CYP51B than the other three stereoisomers. Moreover, enantioselective metabolisms of (1S, 5R)-metconazole and (1R, 5S)-metconazole by Fusarium graminearum Schw were investigated through NMR-based metabolomics. The amounts of alanine, arginine, acetate, ethanol, and dimethylamine produced in the presence of (1R, 5S)-metconazole were significantly higher than corresponding amounts in the presence of (1S, 5R)-metconazole, whereas the amounts of glucose, glycerol, glutamate, methionine, and trimethylamine formed in the presence of (1R, 5S)-metconazole were much less than those in the presence of (1S, 5R)-metconazole. This systematic investigation of metconazole stereoisomers would provide a new perception of metconazole in stereoisomeric level, including bioactivities, metabolic behaviors and antifungal mechanism.


Assuntos
Fungicidas Industriais , Alternaria , Antifúngicos/toxicidade , Fungicidas Industriais/toxicidade , Fusarium , Simulação de Acoplamento Molecular , Estereoisomerismo , Triazóis/toxicidade
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