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1.
Am J Respir Cell Mol Biol ; 70(3): 215-225, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38061028

RESUMO

The function of type 2 immunity and mechanisms underlying the initiation of type 2 immunity after sepsis-induced lung injury remain unclear. Sphingosine-1-phosphate receptor 2 (S1PR2) has been demonstrated to modulate type 2 immunity in the context of asthma and pulmonary fibrosis. Thus, this study aims to investigate the role of type 2 immunity and whether and how S1PR2 regulates type 2 immunity in sepsis. Peripheral type 2 immune responses in patients with sepsis and healthy control subjects were assessed. The impact of S1PR2 on type 2 immunity in patients with sepsis and in a murine model of sepsis was further investigated. The type 2 innate immune responses were significantly increased in the circulation of patients 24 hours after sepsis, which was positively related to clinical complications and negatively correlated with S1PR2 mRNA expression. Animal studies showed that genetic deletion or pharmacological inhibition of S1PR2 induced type 2 innate immunity accumulation in the post-septic lungs. Mechanistically, S1PR2 deficiency promoted macrophage-derived interleukin (IL)-33 increase and the associated type 2 response in the lung. Furthermore, S1PR2-regulated IL-33 from macrophages mitigated lung injury after sepsis in mice. In conclusion, a lack of S1PR2 modulates the type 2 immune response by upregulating IL-33 release from macrophages and alleviates sepsis-induced lung injury. Targeting S1PR2 may have potential therapeutic value for sepsis treatment.


Assuntos
Lesão Pulmonar , Sepse , Animais , Humanos , Camundongos , Interleucina-33 , Macrófagos , Sepse/complicações , Receptores de Esfingosina-1-Fosfato
2.
Opt Express ; 32(7): 11774-11793, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571017

RESUMO

The imaging spectrometer's high performance in practical applications may be compromised by environmental factors, particularly temperature variations, posing a challenge to its stability. Temperature fluctuations can induce spectral shift, directly impacting the accuracy of spectral measurements, subsequently influencing the precision of radiometric measurements. To address this issue, this study investigates a dual-channel UV imaging spectrometer. This instrument boasts a wavelength calibration accuracy of 0.01 nm. This paper conducts an in-depth analysis of the various mechanisms through which temperature changes influence the spectral line offset in the imaging spectrometer, integrating actual orbital temperature data to discuss the instrument's temperature load settings. The impact of temperature on spectral shift is examined using finite element analysis and optical design software. Estimations of spectral shift were made based on temperature variations. Simulation results indicated that the maximum deviation of spectral shift is estimated at 0.018 nm under a temperature condition of 16 ± 1°C. Under a more controlled orbital temperature condition (16 ± 0.3°C), the maximum deviation of spectral shift decreased to 0.01 nm. Experimental data revealed that at 16 ± 1°C, the maximum deviation of spectral shift did not exceed 0.01 nm. This effectively corroborates our theoretical analysis. The relationship between temperature and spectral shift offers a crucial theoretical foundation for calibrating spectral measurements and managing the thermal conditions of the instrument.

3.
Environ Sci Technol ; 58(28): 12542-12553, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38967661

RESUMO

Although exogenous chemicals frequently exhibit a biphasic response in regulating plant growth, characterized by low-dose stimulation and high-dose inhibition, the underlying mechanisms remain elusive. This study demonstrates, for the first time, the compensatory function of rhizosphere microbiota in assisting plants to withstand pesticide stress. It was observed that pak choi plants, in response to foliar-spraying imidacloprid at both low and high doses, could increase the total number of rhizosphere bacteria and enrich numerous beneficial bacteria. These bacteria have capabilities for promoting plant growth and degrading the pesticide, such as Nocardioides, Brevundimonas, and Sphingomonas. The beneficial bacterial communities were recruited by stressed plants through increasing the release of primary metabolites in root exudates, such as amino acids, fatty acids, and lysophosphatidylcholines. At low doses of pesticide application, the microbial compensatory effect overcame pesticide stress, leading to plant growth promotion. However, with high doses of pesticide application, the microbial compensatory effect was insufficient to counteract pesticide stress, resulting in plant growth inhibition. These findings pave the way for designing improved pesticide application strategies and contribute to a better understanding of how rhizosphere microbiota can be used as an eco-friendly approach to mitigate chemical-induced stress in crops.


Assuntos
Praguicidas , Rizosfera , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Microbiologia do Solo , Microbiota/efeitos dos fármacos , Raízes de Plantas/microbiologia , Raízes de Plantas/efeitos dos fármacos , Estresse Fisiológico
4.
Cell Tissue Bank ; 25(2): 633-648, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38319426

RESUMO

Osteochondral allograft (OCA) transplantation involves grafting of natural hyaline cartilage and supporting subchondral bone into the cartilage defect area to restore its biomechanical and tissue structure. However, differences in biomechanical properties and donor-host matching may impair the integration of articular cartilage (AC). This study analyzed the biomechanical properties of the AC in different regions of different sites of the knee joint and provided a novel approach to OCA transplantation. Intact stifle joints from skeletally mature pigs were collected from a local abattoir less than 8 h after slaughter. OCAs were collected from different regions of the joints. The patella and the tibial plateau were divided into medial and lateral regions, while the trochlea and femoral condyle were divided into six regions. The OCAs were analyzed and compared for Young's modulus, the compressive modulus, and cartilage thickness. Young's modulus, cartilage thickness, and compressive modulus of OCA were significantly different in different regions of the joints. A negative correlation was observed between Young's modulus and the proportion of the subchondral bone (r = - 0.4241, P < 0.0001). Cartilage thickness was positively correlated with Young's modulus (r = 0.4473, P < 0.0001) and the compressive modulus (r = 0.3678, P < 0.0001). During OCA transplantation, OCAs should be transplanted in the same regions, or at the closest possible regions to maintain consistency of the biomechanical properties and cartilage thickness of the donor and recipient, to ensure smooth integration with the surrounding tissue. A 7 mm depth achieved a higher Young's modulus, and may represent the ideal length.


Assuntos
Aloenxertos , Cartilagem Articular , Articulação do Joelho , Animais , Cartilagem Articular/fisiologia , Articulação do Joelho/fisiologia , Articulação do Joelho/cirurgia , Fenômenos Biomecânicos , Suínos , Módulo de Elasticidade , Transplante Ósseo/métodos
5.
Cancer Sci ; 114(3): 908-920, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36308281

RESUMO

Whether proline deficiency is a metabolic vulnerability in colorectal tumors is unknown. The aim of this study was to investigate the effects of proline metabolism-related genes and exogenous proline on the progression of colorectal cancer (CRC). We aimed to further clarify the role of pyrroline-5-carboxylate reductase (PYCR) 2, a key enzyme of proline synthesis, in the regulation of colorectal intraperitoneal metastatic tumors. This study was carried out based on The Cancer Genome Atlas (TCGA) data, database analysis, single-cell functional analysis, tissue microarray, cell experiments, and animal models. We found that, PYCR2 mRNA and protein levels were upregulated in CRC. The mRNA level of PYCR2 was closely related to the prognosis and tumor metastasis of CRC patients. The upregulated PYCR2 expression was at least partly due to low promoter methylation levels. The nomogram constructed based on PYCR2 expression and clinical characteristics of CRC showed good accuracy in predicting lymph node metastasis. Pycr2 knockdown inhibited epithelial-mesenchymal transition (EMT) of mouse CRC cells. Proline supplementation did not rescue the inhibition of mouse CRC cell proliferation and migration by Pycr2 knockdown. Proline supplementation also did not rescue the suppression of subcutaneous tumors and intraperitoneal metastatic tumors in mice by Pycr2 knockdown. PYCR2 co-expressed genes in TCGA-CRC were enriched in epigenetic modification-related biological processes and molecular functions. Four small molecules with the lowest binding energy to the PYCR2 protein were identified. Collectively, Pycr2 knockdown inhibited mouse CRC progression in a proline-independent approach. PYCR2 may be a promising tumor metastasis predictor and therapeutic target in CRC.


Assuntos
Neoplasias Colorretais , Camundongos , Animais , Prognóstico , Proliferação de Células , RNA Mensageiro , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal/genética , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral
6.
Environ Sci Technol ; 57(45): 17312-17323, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37907425

RESUMO

Plants have developed an adaptive strategy for coping with biotic or abiotic stress by recruiting specific microorganisms from the soil pool. Recent studies have shown that the foliar spraying of pesticides causes oxidative stress in plants and leads to changes in the rhizosphere microbiota, but the mechanisms by which these microbiota change and rebuild remain unclear. Herein, we provide for the first-time concrete evidence that rice plants respond to the stress of application of the insecticide chlorpyrifos (CP) by enhancing the release of amino acids, lipids, and nucleotides in root exudates, leading to a shift in rhizosphere bacterial community composition and a strong enrichment of the genus Sphingomonas sp. In order to investigate the underlying mechanisms, we isolated a Sphingomonas representative isolate and demonstrated that it is both attracted by and able to consume linolenic acid, one of the root exudates overproduced after pesticide application. We further show that this strain selectively colonizes roots of treated plants and alleviates pesticide stress by degrading CP and releasing plant-beneficial metabolites. These results indicate a feedback loop between plants and their associated microbiota allowing to respond to pesticide-induced stress.


Assuntos
Clorpirifos , Praguicidas , Sphingomonas , Clorpirifos/metabolismo , Sphingomonas/metabolismo , Rizosfera , Bactérias/metabolismo , Plantas/metabolismo , Ácidos Linolênicos/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Microbiologia do Solo
7.
BMC Pulm Med ; 23(1): 262, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37454075

RESUMO

OBJECTIVES: Pulmonary sarcomatoid carcinoma (PSC) is a rare histological type of non-small cell lung cancer (NSCLC). There are no specific treatment guidelines for PSC. For advanced PSC (stage II-IV), the role of chemotherapy is still controversial. The purpose of this study was to investigate the effect of chemotherapy on the prognosis of advanced PSC. METHODS: A total of 960 patients with advanced PSC from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2019 were enrolled in this study. To investigate the prognostic factors, the Cox proportional hazard regression model was conducted. A total of 642 cases were obtained after propensity score matching (PSM). The Kaplan‒Meier method was applied to compare overall survival (OS) and cancer-specific survival (CSS). RESULTS: For all 960 cases included in this study, the Cox proportional hazard model was applied for prognostic analysis. Univariate and multivariate analyses showed that stage, T stage, N stage, M stage, surgery, and chemotherapy were prognostic factors for OS and CSS (P < 0.05). A total of 642 cases were obtained after PSM, with no significant difference between the two groups for all variables. Kaplan‒Meier curves indicated that for OS and CSS, the prognosis was significantly better in the chemotherapy group than in the no-chemotherapy group. CONCLUSIONS: For advanced PSC, chemotherapy can significantly improve the OS and CSS of patients. Chemotherapy should be an important part of PSC treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Pontuação de Propensão , Programa de SEER
8.
Eur Radiol ; 32(2): 1065-1077, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34453574

RESUMO

OBJECTIVES: To assess methods to improve the accuracy of prognosis for clinical stage I solid lung adenocarcinoma using radiomics based on different volumes of interests (VOIs). METHODS: This retrospective study included patients with postoperative clinical stage I solid lung adenocarcinoma from two hospitals, center 1 and center 2. Three databases were generated: dataset A (training set from center 1), dataset B (internal test set from center 1), and dataset C (external validation test from center 2). Disease-free survival (DFS) data were collected. CT radiomics models were constructed based on four VOIs: gross tumor volume (GTV), 3 mm external to the tumor border (peritumoral volume [PTV]0~+3), 6 mm crossing tumor border (PTV-3~+3), and 6 mm external to the tumor border (PTV0~+6). The area under the receiver operating characteristic curve (AUC) was used to compare the model accuracies. RESULTS: A total of 334 patients were included (204 and 130 from centers 1 and 2). The model using PTV-3~+3 (AUC 0.81 [95% confidence interval {CI}: 0.75, 0.94], 0.81 [0.63, 0.90] for datasets B and C) outperformed the other three models, GTV (0.73 [0.58, 0.81], 0.73 [0.58, 0.83]), PTV0~+3 (0.76 [0.52, 0.87], 0.75 [0.60, 0.83]), and PTV0~+6 (0.72 [0.60, 0.81], 0.69 [0.59, 0.81]), in datasets B and C, all p < 0.05. CONCLUSIONS: A radiomics model based on a VOI of 6 mm crossing tumor border more accurately predicts prognosis of clinical stage I solid lung adenocarcinoma than that based on VOIs including overall tumor or external rims of 3 mm and 6 mm. KEY POINTS: • Radiomics is a useful approach to improve the accuracy of prognosis for stage I solid adenocarcinoma. • The radiomics model based on VOIs that includes 3 mm within and external to the tumor border (peritumoral volume [PTV]-3~+3) outperformed models that included either only the tumor itself or those that only included the peritumoral volume.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Prognóstico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
9.
Environ Sci Technol ; 56(12): 7883-7894, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35593893

RESUMO

Antibiotics could enter farmlands through sewage irrigation or manure application, causing combined pollution with pesticides. Antibiotics may affect the environmental fate of pesticides and even increase their bioavailability. In this study, the influence of monensin on the degradation, toxicity, and availability of atrazine in soil-earthworm microcosms was investigated. Monensin inhibited the degradation of atrazine, changed the metabolite patterns in soil, and increased the bioavailability of atrazine in earthworms. Atrazine and monensin had a significant synergistic effect on earthworms in the acute toxic test. In long-term toxicity tests, co-exposure of atrazine and monensin also led to worse effects on earthworms including oxidative stress, energy metabolism disruption, and cocoon production compared to single exposure. The expression of tight junction proteins was down-regulated significantly by monensin, indicating that the intestinal barrier of earthworms was weakened, possibly causing the increased bioavailability of atrazine. The expressions of heat shock protein 70 (Hsp70) and reproductive and ontogenetic factors (ANN, TCTP) were all downregulated in binary exposure, indicating that the resilience and cocoon production of earthworms were further weakened under combined pollution. Monensin disturbed the energy metabolism and weakened the intestinal barrier of earthworms. These results showed that monensin increased the risks of atrazine in agricultural areas.


Assuntos
Atrazina , Oligoquetos , Praguicidas , Poluentes do Solo , Animais , Antibacterianos/farmacologia , Atrazina/toxicidade , Monensin/farmacologia , Monensin/toxicidade , Praguicidas/metabolismo , Solo , Poluentes do Solo/metabolismo
10.
Bull Environ Contam Toxicol ; 108(6): 1081-1087, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35254467

RESUMO

The aim of the present study was to compare the predictive ability of four chemical extraction methods, i.e., Tenax, hydroxypropyl[ß]cyclodextrin (HPCD), n-butanol and low-molecular-weight-organic-acids (LMWOA), for predicting the bioavailability and phytotoxicity of soil phthalic acid esters to the green vegetable Shanghaiqing (SHQ). Results showed that the extraction ability of different extraction methods varies significantly. For dibutyl phthalate (DBP), the extraction ability followed the order of Tenax > LMWOA > HPCD > n-butanol. For di-(2-ethylhexyl) phthalate (DEHP), the order of the extraction ability was n-butanol > HPCD > Tenax > LMWOA. All the extraction methods underestimated the DBP concentration while overestimating the DEHP concentration accumulated by SHQ. The concentrations of DBP and DEHP extracted by Tenax were most related to the concentrations accumulated by SHQ and the phytotoxicity indicators of SHQ. Tenax can serve as a good chemical extractant to assess the bioavailability and phytotoxicity of soil DBP and DEHP to SHQ.


Assuntos
Brassica rapa , Dietilexilftalato , Ácidos Ftálicos , Poluentes do Solo , 1-Butanol , Disponibilidade Biológica , Dibutilftalato , Ésteres/análise , Ácidos Ftálicos/análise , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Verduras
11.
J Exp Bot ; 72(15): 5673-5686, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-33987653

RESUMO

Inoculation with pollution-degrading endophytes boosts the catabolism of residual contaminants and promotes the pollution adaptation of host plants. We investigated the interaction pattern between Sphingomonas strain HJY-rfp, a chlorpyrifos-degrading endophytic bacterium, and rice (Oryza sativa) under pesticide stress using hydroponic cultivation. We observed a notable trend of endophytic root colonization in rice plants treated with 10 mg l-1 chlorpyrifos solution, and after 24 h the migration of HJY-rfp enhanced the chlorpyrifos degradation rate in leaves and stems by 53.36% and 40.81%, respectively. Critically, the rice root exudate profile (organic acids and amino acids) changed under chlorpyrifos stress, and variations in the contents of several components affected the chemotactic behaviour of HJY-rfp. HJY-rfp colonization dramatically activated defensive enzymes, which enabled efficient scavenging of reactive oxygen species, and led to 9.8%, 22.5%, and 41.9% increases in shoot length, fresh weight, and accumulation of total chlorophyll, respectively, in rice suffering from oxidative damage by chlorpyrifos. Endophytic colonization caused up-regulation of detoxification genes that have shown a significant positive correlation with chlorpyrifos degradation in vivo. Collectively, our results demonstrate that agrochemical stress causes plants to actively recruit specific symbiotic microbes to detoxify contaminants and survive better under pollution conditions.


Assuntos
Clorpirifos , Oryza , Sphingomonas , Endófitos , Exsudatos e Transudatos , Raízes de Plantas
12.
Environ Res ; 189: 109953, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32980024

RESUMO

Phthalates are plasticizers and are ubiquitously detected in the environment, frequently at mg/kg levels. The present study aimed to evaluate the effects of dibutyl phthalate (DBP) on germination, growth, enzyme activity, phytohormone homeostasis and bacterial communities of two cultivars of Brassica rapa var. chinensis. The germination rate was decreased up to 20% compared to the control, and the growth of the vegetables was severely inhibited at the early stage when exposed to DBP at 20 mg/kg. Antioxidant defense enzyme activities and malondialdehyde (MDA) content increased upon exposure to DBP. A dose-response of auxin (IAA) was observed after a 2 d exposure. Gibberellin (GA3) and abscisic acid (ABA) responded at day 10 under DBP stress. GA3 did not show a clear dose-response effect and ABA increased about 3 times as the DBP concentration increased from 2 to 20 mg/L. Microbial population shifts were observed, especially in rhizosphere soil and roots. No obvious change occurred for the α diversity of rhizospheric bacteria among different treatments. Chao1, Shannon and Simpson indices of the root endophytic bacteria showed a decreasing trend with increasing DBP supplementation, while all the indices increased in shoot endophytic bacteria in comparison to the control. The results indicated that exposure to DBP may compromise the fitness of the leafy vagetables and alter the endophytic and rhizospheric bacteria, which might further affect the nutrients of the vegetables and alter ecosystem functions.


Assuntos
Brassica rapa , Poluentes do Solo , Dibutilftalato/toxicidade , Ecossistema , Homeostase , Reguladores de Crescimento de Plantas , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
13.
Ecotoxicol Environ Saf ; 189: 109913, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31735369

RESUMO

The prevalence of microplastics in aquatic environments has raised concerns about their availability and risks to aquatic biota. Since fish is an important source of animal protein for human beings, the occurrence and potential impacts of microplastics in fishes deserve special attention. Although there have been an increasing number of studies concerning microplastics ingestion and effects in fish, review papers specifically focusing on this issue are few. This review summarized the current knowledge about the bioavailability and toxicity of microplastics to fish species. By collating literatures, it can be concluded that microplastics contamination could occur in almost all types of aquatic habitats around the globe. Both field and laboratory studies suggest that fishes are very susceptible to microplastics ingestion. Compared with marine species, freshwater fishes have been less studied. Microplastics alone or in combination with other contaminants could cause various health problems to fish after exposure. There still exist some debates over the environmental relevance of the laboratory-based effect studies and the relative contribution of microplastics in increasing the exposure of fish to hazardous chemicals. Hopefully, this review could extend the current knowledge on the ecotoxicological impacts of microplastics contamination to fish and provide guidance for future research.


Assuntos
Peixes/fisiologia , Microplásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Disponibilidade Biológica , Biota , Ecossistema , Monitoramento Ambiental , Água Doce , Humanos , Plásticos/toxicidade , Alimentos Marinhos
14.
Ecotoxicol Environ Saf ; 196: 110551, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32244120

RESUMO

The widespread usage of plastic film increased the content of phthalic acid esters (PAEs) in the environment, causing PAE residue in vegetables and subsequently increasing health risks to humans when consuming them. In this work, the presence, distribution and risk assessment of 15 PAEs in soils and peppers from suburban plastic film pepper-growing greenhouses were investigated. The total PAE contents in soil and pepper samples ranged from 320.1 to 971.2 µg/kg (586.3 µg/kg on average) and from 196.6 to 304.2 µg/kg (245.4 µg/kg on average), respectively. Di (2-ethyl)hexyl, dibutyl and diisobutyl phthalates (DEHP, DnBP and DiBP, respectively) were the most abundant in both soil and pepper samples. Specifically, DEHP showed the highest content in soils, while the DnBP content was the highest in peppers. The total PAE content in soils from pepper-greenhouses was much lower than in the agricultural soils mulched with plastic films, but significantly higher than in the agricultural soils from open uncovered fields. The total PAE content in peppers decreased as the service life of plastic film greenhouses increased. Correlation analysis suggested that the difference in distribution and accumulation behaviors of individual PAEs in greenhouse systems was correlated with their physicochemical properties. The non-cancer and carcinogenic risks of priority PAEs show low risks of PAEs detected in pepper and soil samples from the suburban plastic film greenhouses to human health.


Assuntos
Produção Agrícola/métodos , Ácidos Ftálicos/análise , Plásticos/química , Poluentes do Solo/análise , Solo/química , Verduras/química , China , Dibutilftalato/análogos & derivados , Dibutilftalato/análise , Ésteres , Contaminação de Alimentos/análise , Humanos , Medição de Risco
15.
Pestic Biochem Physiol ; 167: 104608, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32527438

RESUMO

Triflumezopyrim, a novel mesoionic chemical insecticide, is promoted as a powerful tool for control of susceptible and resistant hopper species in rice throughout Asia. For a newly commercialized insecticide it is important to establish susceptibility baseline, conduct susceptibility monitoring, and assess the risk of resistance via artificial selection to provide foundational information on designing resistance management strategy. The susceptibility baseline of triflumezopyrim was established for three rice planthopper species, Nilarpavata lugens (Stål), Sogatella furcifera (Horváth) and Laodelphax striatellus (Fallén). The LD50 of triflumezopyrim was 0.026, 0.032 and 0.094 ng/individual for the adults of the susceptible strains of S. furcifera, L. striatellus and N. lugens, respectively, determined by a topical application method. Using a rice stem (seedling) dipping method, the LC50 was determined as 0.042, 0.024 and 0.150 mg/L for the nymphs (3rd instar) of the three hopper species, respectively. In the meanwhile, the LC50 of Pyraxalt™ (triflumezopyrim 10% SC) was 0.064 mg/L for the N. lugens susceptible strain. Furthermore, the susceptibility of triflumezopyrim and other five neonicotinoid insecticides were monitored for N. lugens field populations collected from major rice production areas in China in 2015-2019. All monitored populations were susceptible to triflumezopyrim (0.5 to 3.9-fold resistance ratio), and showed no cross-resistance to the other five neonicotinoids. These results suggested that triflumezopyrim is a good option to control resistant N. lugens. In addition, a field-collected population of N. lugens was artificially selected with triflumezopyrim for 20 generations and resulted in 3.5-fold increase in LC50 from F0 and 6.0-fold increase from that of the susceptible strain. The realized heritability (h2) of resistance was estimated as 0.0451 by using threshold trait analysis. With this h2 value, the projected triflumezopyrim resistance development (a 10-fold increase in LC50) would be expected after 30.3 or 24.0 generations if 80% or 90% of the population was killed at each generation.


Assuntos
Hemípteros , Inseticidas , Oryza , Animais , China , Resistência a Inseticidas , Piridinas , Pirimidinonas , Medição de Risco
16.
J Environ Manage ; 253: 109636, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678688

RESUMO

Dibutyl phthalate (DBP) is a frequently detected farmland contaminant that is harmful to the environment and human health. In this study, a DBP-degrading endophytic Bacillus siamensis strain T7 was immobilized in rice husk-derived biochar for bioremediation of DBP-polluted agricultural soils. The effects of this microbe-biochar composite on the soil prokaryotic community and the mechanism by which it regulates DBP degradation, were also investigated. A supplement of T7-biochar composite not only significantly boosted DBP biodegradation in soil by raising the DBP degradation rate constant and half-life from 0.1979 d-1 and 2.3131 d to 0.2434 d-1 and 2.1062 d, respectively, but also impeded DBP uptake by leafy vegetables. The general bioremediation effect of T7-biochar alliance excelled pure T7 suspensions and biochar, by trapping more DBP and boosting its complete degradation in soil. Besides, the combination of strain T7 and biochar can increase the proportion of some beneficial bacteria and boost the functional diversity of soil prokaryotic community, then to a certain extent may reverse the negative effect of DBP pollution on the agricultural soils. These results indicate that the rice-husk-derived biochar is a proper media when utilizing functional microbes into environmental treatment. Overall, T7-biochar composite is a promising soil modifier for soil bioremediation and the production of DBP-free crops.


Assuntos
Bacillus , Poluentes do Solo , Biodegradação Ambiental , Carvão Vegetal , Dibutilftalato , Humanos , Solo , Verduras
17.
Bull Environ Contam Toxicol ; 105(6): 868-873, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33211134

RESUMO

Arsenic (As) contamination in terrestrial and aquatic environments is a well-known global environmental problem. The biooxidation of arsenite [As(III)] and subsequent arsenate [As(V)] removal have increasingly been used for remediation of As-polluted groundwater. However, little is known about As(III) oxidation by microalgae, especially those from saltwater environments. In this study, we investigated As(III) toxicity and oxidation in the marine microalga Dunaliella salina in the presence of different phosphate concentrations. The results of the As(III) toxicity experiments showed that D. salina was tolerant to As(III) (5.4 ± 0.31 mg As L-1 at 72 h of culture). The As(V) percentage in the P-enriched (11.2 mg L-1) medium was 7.2-fold greater than in the P-deficient one after 24-h exposure, indicating As(III) oxidation by D. salina was more pronounced with increased phosphate levels. Treatment of As(III) with and without 2,4-dinitrophenol (DNP) on the algal cells showed that As(III) oxidation occurred mainly on the cell surface and in the cytoplasm of D. salina. The results of this study suggest that transformation of As(III) into As(V) may be an important pathway of detoxification in D. salina and that phosphate plays a key role in this oxidation process.


Assuntos
Arsenitos/metabolismo , Microalgas/metabolismo , Fosfatos/metabolismo , Arseniatos , Arsênio/metabolismo , Oxirredução
18.
Opt Express ; 27(21): 29510-29520, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684211

RESUMO

As the most important class of self-imaging beams, Bessel Beams (BBs) have been extensively studied, and various applications in optical trapping, communication, imaging and quantum studies have been found. In this paper, we propose a new method to generate arbitrary (quasi-) BB arrays by using a single LED light source. The method is simpler, cheaper, and more compatible than other existing methods. The key idea of the proposed method is to form spatially controllable incoherent point sources used to generate BB array imaging. Detailed theoretical deduction, analysis of properties of the generated BB array and comparison with those generated by coherent light sources are depicted. Further application to confocal imaging shows that the BB array is promising for fast, super depth-of-field imaging and multi-particle optical manipulations.

19.
J Opt Soc Am A Opt Image Sci Vis ; 36(6): 944-949, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31158125

RESUMO

Imaging techniques through turbid materials have been extensively studied in recent years. The challenge now is to recover objects in a large field of view with depth-resolving ability. We present a method to image through a thin scattering layer automatically with the depth of the object detectable. By revealing the wavelength-depth-matching relation based on the axial memory effect, this method can automatically search the optimal wavelength of the reference light and compute the depth of the object. The no-reference image quality assessment function and rule-based searching algorithm are used in the searching process. The proposed method is promising for dynamic object tracking.

20.
J Sep Sci ; 42(19): 3141-3151, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31376226

RESUMO

A simple and efficient multiresidue method using dispersive solid phase extraction and liquid chromatography coupled with tandem mass spectrometry was developed for the targeted analysis of indaziflam and its five metabolites (indaziflam-diaminotriazine, indaziflam-carboxylic acid, indaziflam-triazine indanone, indaziflam-hydroxyethyl, and indaziflam-olefin) in pitaya samples (including roots, plants, flowers, peels, pulp, and whole fruit). The analytes were extracted with acetonitrile, and the extracts were purified using multiwalled carbon nanotubes. The method was validated using pitaya samples spiked at 0.5, 5, and 50 µg/kg, and the average recoveries varied from 61.1 to 103.7% with relative standard deviations lower than 12.7% (n = 5). This method exhibited sufficient linearity within the concentration range of 0.1-100 µg/L. The limits of detection and quantification were in the ranges of 0.001-0.1 and 0.003-0.3 µg/kg, respectively. The method was successfully applied to analyze pitaya samples in Nanning, and no indaziflam or its metabolites were detected in the samples analyzed.


Assuntos
Cactaceae/química , Indenos/análise , Extração em Fase Sólida , Triazinas/análise , Cromatografia Líquida de Alta Pressão , Frutas/química , Frutas/metabolismo , Indenos/metabolismo , Espectrometria de Massas em Tandem , Triazinas/metabolismo
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