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1.
Environ Sci Technol ; 58(8): 3895-3907, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38356175

RESUMO

Volatilization of lower-chlorinated polychlorinated biphenyls (LC-PCBs) from sediment poses health threats to nearby communities and ecosystems. Biodegradation combined with black carbon (BC) materials is an emerging bioaugmentation approach to remove PCBs from sediment, but development of aerobic biofilms on BC for long-term, sustained LC-PCBs remediation is poorly understood. This work aimed to characterize the cell enrichment and activity of biphenyl- and benzoate-grown Paraburkholderia xenovorans strain LB400 on various BCs. Biphenyl dioxygenase gene (bphA) abundance on four BC types demonstrated corn kernel biochar hosted at least 4 orders of magnitude more attached cells per gram than other feedstocks, and microscopic imaging revealed the attached live cell fraction was >1.5× more on corn kernel biochar than GAC. BC characteristics (i.e., sorption potential, pore size, pH) appear to contribute to cell attachment differences. Reverse transcription qPCR indicated that BC feedstocks significantly influenced bphA expression in attached cells. The bphA transcript-per-gene ratio of attached cells was >10-fold more than suspended cells, confirmed by transcriptomics. RNA-seq also demonstrated significant upregulation of biphenyl and benzoate degradation pathways on attached cells, as well as revealing biofilm formation potential/cell-cell communication pathways. These novel findings demonstrate aerobic PCB-degrading cell abundance and activity could be tuned by adjusting BC feedstocks/attributes to improve LC-PCBs biodegradation potential.


Assuntos
Compostos de Bifenilo , Burkholderiaceae , Carvão Vegetal , Bifenilos Policlorados , Benzoatos , Biodegradação Ambiental , Carbono , Ecossistema , Bifenilos Policlorados/metabolismo , Dioxigenases/química , Dioxigenases/metabolismo
2.
Bioorg Chem ; 146: 107278, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38484586

RESUMO

VEGFR, a receptor tyrosine kinase inhibitor (TKI), is an important regulatory factor that promotes angiogenesis and vascular permeability. It plays a significant role in processes such as tumor angiogenesis, tumor cell invasion, and metastasis. VEGFR is mainly composed of three subtypes: VEGFR-1, VEGFR-2, and VEGFR-3. Among them, VEGFR-2 is the crucial signaling receptor for VEGF, which is involved in various pathological and physiological functions. At present, VEGFR-2 is closely related to a variety of cancers, such as non-small cell lung cancer (NSCLC), Hepatocellular carcinoma, Renal cell carcinoma, breast cancer, gastric cancer, glioma, etc. Consequently, VEGFR-2 serves as a crucial target for various cancer treatments. An increasing number of VEGFR inhibitors have been discovered to treat cancer, and they have achieved tremendous success in the clinic. Nevertheless, VEGFR inhibitors often exhibit severe cytotoxicity, resistance, and limitations in indications, which weaken the clinical therapeutic effect. In recent years, many small molecule inhibitors targeting VEGFR have been identified with anti-drug resistance, lower cytotoxicity, and better affinity. Here, we provide an overview of the structure and physiological functions of VEGFR, as well as some VEGFR inhibitors currently in clinical use. Also, we summarize the in vivo and in vitro activities, selectivity, structure-activity relationship, and therapeutic or preventive use of VEGFR small molecule inhibitors reported in patents in the past three years (2021-2023), thereby presenting the prospects and insights for the future development of targeted VEGFR inhibitors.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Renais , Neoplasias Pulmonares , Humanos , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/química
3.
J Cell Mol Med ; 27(15): 2123-2135, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37278388

RESUMO

Porphyromonas gingivalis (P. gingivalis) is a pivotal pathogen of periodontitis. Our previous studies have confirmed that mitochondrial dysfunction in the endothelial cells caused by P. gingivalis was dependent on Drp1, which may be the mechanism of P. gingivalis causing endothelial dysfunction. Nevertheless, the signalling pathway induced the mitochondrial dysfunction remains unclear. The purpose of this study was to investigate the role of the RhoA/ROCK1 pathway in regulating mitochondrial dysfunction caused by P. gingivalis. P. gingivalis was used to infect EA.hy926 cells (endothelial cells). The expression and activation of RhoA and ROCK1 were assessed by western blotting and pull-down assay. The morphology of mitochondria was observed by mitochondrial staining and transmission electron microscopy. Mitochondrial function was measured by ATP content, mitochondrial DNA and mitochondrial permeability transition pore openness. The phosphorylation and translocation of Drp1 were evaluated using western blotting and immunofluorescence. The role of the RhoA/ROCK1 pathway in mitochondrial dysfunction was investigated using RhoA and ROCK1 inhibitors. The activation of RhoA/ROCK1 pathway and mitochondrial dysfunction were observed in P. gingivalis-infected endothelial cells. Furthermore, RhoA or ROCK1 inhibitors partly prevented mitochondrial dysfunction caused by P. gingivalis. The increased phosphorylation and mitochondrial translocation of Drp1 induced by P. gingivalis were both blocked by RhoA and ROCK1 inhibitors. In conclusion, we demonstrate that the RhoA/ROCK1 pathway was involved in mitochondrial dysfunction caused by P. gingivalis by regulating the phosphorylation and mitochondrial translocation of Drp1. Our research illuminated a possible new mechanism by which P. gingivalis promotes endothelial dysfunction.


Assuntos
Células Endoteliais , Porphyromonas gingivalis , Células Endoteliais/metabolismo , Transdução de Sinais , Mitocôndrias/metabolismo , Quinases Associadas a rho/metabolismo
4.
Mol Carcinog ; 62(7): 1001-1008, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37067398

RESUMO

Mutations in epidermal growth factor receptor and anaplastic lymphoma kinase are common driver events in non-small cell lung cancer (NSCLC), which are associated with a high frequency of bone metastases (BMs). While the bone marrow represents a specialized immune microenvironment, the immune repertoire of BMs remains unknown. Considering the higher incidence of BMs in driver gene-positive NSCLCs, and the unique biology of the bone, herein, we assessed the infiltrating immune cells and T cell receptor (TCR) profile of BMs in driver-positive NSCLCs. Immune profile of BMs in driver gene-positive NSCLC were assessed in 10 patients, where 6 had driver gene-positive mutation. TCR and bulk RNA sequencing were performed on malignant bone samples. The diversity and clonality of the TCR repertoire were analyzed. The cellular components were inferred from bulk gene expression profiles computationally by CIBERSORT. Although BMs were generally regarded as immune-cold tumors, immune cell composition analyses showed co-existence of cytotoxic and suppressor immune cells in driver-positive BM samples, as compared to primary lung. Analysis of the TCR repertoire indicated a trend of higher diversity and similar clonality in the driver-positive compared with the driver-negative subsets. In addition, we identified two cases that showed the opposite response to immune checkpoint blockade. A comparison of these two patients' BM samples showed more highly amplified clones, fewer M2 macrophages and more activated natural killer cells in the responder. In summary, BMs in NSCLC are heterogeneous in their immune microenvironment, which might be related to differential clinical outcomes to immune checkpoint blockade.


Assuntos
Neoplasias Ósseas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Pulmão/patologia , Neoplasias Ósseas/genética , Receptores de Antígenos de Linfócitos T/genética , Microambiente Tumoral/genética
5.
Pharmacoepidemiol Drug Saf ; 32(11): 1189-1199, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37655831

RESUMO

PURPOSE: The aim of this study was to evaluate the efficacy and safety of moxifloxacin monotherapy for the treatment of uncomplicated pelvic inflammatory disease (uPID). METHODS: The literatures from PubMed, ScienceDirect, Google Scholar, Cochrane library and the http://clinicaltrials.gov/ were retrieved until February 2023. Only randomized controlled trials (RCTs) comparing the efficacy and safety of moxifloxacin with other antibiotics for treating uPID were included. The primary outcomes were clinical cure rate (CCR), bacteriological success rates (BSR) and risk of drug-related adverse events (AEs). We used random-effects modelled meta-analysis, trial sequential analysis, and the Grading of Recommendations Assessment, Development, and Evaluation. This study was registered in the International Prospective Register of Systematic Reviews (registration number: CRD42023428751). RESULTS: A total of four RCTs that enrolled 3201 women patients with uPID were included. In the per-protocol populations, no significant difference was observed between patients given moxifloxacin and those given other antibiotics with regard to CCR at test-of-cure (TOC) (2485 patients, odds ratio [OR] = 0.84, 95% confidence interval [CI] 0.68-1.04, p = 0.12). Similarly, there was no statistically significant difference between patients given moxifloxacin and those given other antibiotics in terms of BSR at TOC (471 patients, OR = 1.17, 95% CI 0.70-1.96, p = 0.56) in the microbiologically valid population. However, drug-related AEs occurred less frequently with moxifloxacin than with other antibiotics (2973 patients, OR = 0.74, 95% CI 0.64-0.86, p < 0.0001), especially gastrointestinal AEs (2973 patients, OR = 0.59, 95% CI 0.47-0.74, p < 0.00001). CONCLUSIONS: In the treatment of uPID, moxifloxacin monotherapy can achieve similar efficacy as other combination therapy regimens. Moreover, moxifloxacin had a better safety profile than that of comparators. Based on its additional advantages (i.e., better safety profile, no dosage adjustment and better compliance), moxifloxacin may be a more fascinating option compared with the currently used regimens.

6.
J Nanobiotechnology ; 21(1): 379, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37848975

RESUMO

BACKGROUND: Brain-derived neurotrophic factor (BDNF) with neuronic development and function is a promising therapeutic agent for treating depressive disorder, according to the neurotrophin hypothesis. However, the delivery of BDNF into the brain is not easy as these large protein molecules cannot efficiently cross the blood-brain barrier (BBB) and easily suffer oxidative damage in vivo. Therefore, the quercetin-based alginate nanogels (quercetin nanogels) loaded with BDNF have been developed, which could efficiently bypass the BBB via the nose-to-brain pathway and protect BDNF from oxidative damage, providing an effective route for the therapy of depressive disorders by intranasal delivery. RESULTS: Quercetin nanogels exhibited uniform size distribution, excellent biocompatibility, and potent antioxidant and anti-inflammatory activities. Quercetin nanogels in the thermosensitive gel achieved sustained and controlled release of BDNF with non-Fick's diffusion, exhibited rapid brain distribution, and achieved nearly 50-fold enhanced bioavailability compared to oral quercetin. Quercetin nanogels as a therapeutic drug delivery carrier exerted antidepressant effects on reserpine-induced rats, effectively delivered BDNF to reverse despair behavior in stress-induced mice, and exhibited antidepressant effects on chronic mild unpredictable stimulation (CUMS) rats. These antidepressant effects of BDNF-Quercetin nanogels for CUMS rats are associated with the regulation of the glutamatergic system, PI3K-Akt, and BDNF-TrkB signaling pathway. CONCLUSIONS: In this study, we provide a promising strategy for brain delivery of BDNF for treating depressive disorders, effectively achieved through combining quercetin nanogels and intranasal administration.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Quercetina , Ratos , Camundongos , Animais , Quercetina/farmacologia , Quercetina/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressão/tratamento farmacológico , Depressão/metabolismo , Nanogéis , Alginatos , Fosfatidilinositol 3-Quinases/metabolismo , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Antidepressivos/metabolismo , Hipocampo , Modelos Animais de Doenças
7.
Ecotoxicol Environ Saf ; 249: 114481, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38321693

RESUMO

The impact of atmospheric deposition of cadmium (Cd) in cereal crops has become a global concern. Enhanced lignin content was expected to benefit the plant performance against Cd exposure. To date, however, the underlying mechanisms of lignin regulating foliar Cd absorption in rice (Oryza sativa L.) and its effect on grain yield remains unclear. In present study, the effect and mechanism of rice in response to leaf Cd exposure were investigated using 113Cd stable isotope and a lignin-increased rice mutant. The highest Cd uptake efficiency and uptake amount was observed in wild type (WT) plant grown in the maturity period, which were 3-fold higher than in mutant plant. Compared to WT, the mutant exhibited 14.75% and 25.43% higher contents in G- and S-unit of lignin monomers. Lignin biosynthesis and polymerization related genes (OsPAL/OsCOMT/Os4CL3/OsLAC5/OsLAC15) were significantly up-regulated in mutants. In addition, the enzyme activities involved in the above process were also significantly increased by 1.24-1.49-fold. The increased Cd retention in cell wall and decreased gene expression levels of OsNRAMP5, OsHMA3 and OsIRT1 in mutant indicated that lignin effectively inhibited Cd transportion in plant tissues. Moreover, the antioxidant capacity and photosynthesis efficiency in mutant plant were obviously improved, leading to higher Cd tolerance and increased grain yield. Our results revealed the molecular and physiological mechanisms of enhanced lignin regulating foliar Cd absorption and yield in rice, and provided the valuable rice genotype to ensure food safety.


Assuntos
Oryza , Poluentes do Solo , Cádmio/metabolismo , Lignina/metabolismo , Oryza/metabolismo , Transporte Biológico , Antioxidantes/metabolismo , Grão Comestível/química , Poluentes do Solo/análise
8.
Molecules ; 28(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36615595

RESUMO

Given the labor-consuming nature of model establishment, model transfer has become a considerable topic in the study of near-infrared (NIR) spectroscopy. Recently, many new algorithms have been proposed for the model transfer of spectra collected by the same types of instruments under different situations. However, in a practical scenario, we need to deal with model transfer between different types of instruments. To expand model applicability, we must develop a method that could transfer spectra acquired from different types of NIR spectrometers with different wavenumbers or absorbance. Therefore, in our study, we propose a new methodology based on improved principal component analysis (IPCA) for calibration transfer between different types of spectrometers. We adopted three datasets for method evaluation, including public pharmaceutical tablets (dataset 1), corn data (dataset 2), and the spectra of eight batches of samples acquired from the plasma ethanol precipitation process collected by FT-NIR and MicroNIR spectrometers (dataset 3). In the calibration transfer for public datasets, IPCA displayed comparable results with the classical calibration transfer method using piecewise direct standardization (PDS), indicating its obvious ability to transfer spectra collected from the same types of instruments. However, in the calibration transfer for dataset 3, our proposed IPCA method achieved a successful bi-transfer between the spectra acquired from the benchtop and micro-instruments with/without wavelength region selection. Furthermore, our proposed method enabled improvements in prediction ability rather than the degradation of the models built with original micro spectra. Therefore, our proposed method has no limitations on the spectrum for model transfer between different types of NIR instruments, thus allowing a wide application range, which could provide a supporting technology for the practical application of NIR spectroscopy.


Assuntos
Algoritmos , Calibragem , Análise de Componente Principal , Padrões de Referência
9.
Appl Intell (Dordr) ; 53(9): 10766-10788, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36039116

RESUMO

Domain adaptation, as an important branch of transfer learning, can be applied to cope with data insufficiency and high subject variabilities in motor imagery electroencephalogram (MI-EEG) based brain-computer interfaces. The existing methods generally focus on aligning data and feature distribution; however, aligning each source domain with the informative samples of the target domain and seeking the most appropriate source domains to enhance the classification effect has not been considered. In this paper, we propose a dual alignment-based multi-source domain adaptation framework, denoted DAMSDAF. Based on continuous wavelet transform, all channels of MI-EEG signals are converted respectively and the generated time-frequency spectrum images are stitched to construct multi-source domains and target domain. Then, the informative samples close to the decision boundary are found in the target domain by using entropy, and they are employed to align and reassign each source domain with normalized mutual information. Furthermore, a multi-branch deep network (MBDN) is designed, and the maximum mean discrepancy is embedded in each branch to realign the specific feature distribution. Each branch is separately trained by an aligned source domain, and all the single branch transfer accuracies are arranged in descending order and utilized for weighted prediction of MBDN. Therefore, the most suitable number of source domains with top weights can be automatically determined. Extensive experiments are conducted based on 3 public MI-EEG datasets. DAMSDAF achieves the classification accuracies of 92.56%, 69.45% and 89.57%, and the statistical analysis is performed by the kappa value and t-test. Experimental results show that DAMSDAF significantly improves the transfer effects compared to the present methods, indicating that dual alignment can sufficiently use the different weighted samples and even source domains at different levels as well as realizing optimal selection of multi-source domains.

10.
Opt Express ; 30(3): 4312-4326, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35209670

RESUMO

Metasurfaces have made great progress in the last decade for generating miniature and integrated optical devices. The optical properties of metasurfaces can be tuned dynamically by integrating with phase-change materials. However, the efficiency of tunable metasurfaces remains a bit low, which is a disadvantage for the realistic applications of metasurfaces. Here, we demonstrate the tunable dielectric metasurfaces by structuring the phase-change material Ge2Sb2Te5. The unit cell of metasurface is composed of several Ge2Sb2Te5 nanopillars with different geometric parameters, and the incident light interacts with different nanopillars at diverse phases of Ge2Sb2Te5, leading to various functions. By elaborately arranging the Ge2Sb2Te5 nanopillars, various tunable optical devices have been realized, including tunable beam steering, reconfigurable metalens and switchable wave plate. The refractive direction, focal length and polarization state can be tuned through the phase transition of Ge2Sb2Te5. The phase-change metasurfaces based on Ge2Sb2Te5 nanostructures could be used in cameras, optical microscopy and adaptive optics.

11.
Glob Chang Biol ; 28(22): 6696-6710, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36056462

RESUMO

Fungi are highly diverse organisms, which provide multiple ecosystem services. However, compared with charismatic animals and plants, the distribution patterns and conservation needs of fungi have been little explored. Here, we examined endemicity patterns, global change vulnerability and conservation priority areas for functional groups of soil fungi based on six global surveys using a high-resolution, long-read metabarcoding approach. We found that the endemicity of all fungi and most functional groups peaks in tropical habitats, including Amazonia, Yucatan, West-Central Africa, Sri Lanka, and New Caledonia, with a negligible island effect compared with plants and animals. We also found that fungi are predominantly vulnerable to drought, heat and land-cover change, particularly in dry tropical regions with high human population density. Fungal conservation areas of highest priority include herbaceous wetlands, tropical forests, and woodlands. We stress that more attention should be focused on the conservation of fungi, especially root symbiotic arbuscular mycorrhizal and ectomycorrhizal fungi in tropical regions as well as unicellular early-diverging groups and macrofungi in general. Given the low overlap between the endemicity of fungi and macroorganisms, but high conservation needs in both groups, detailed analyses on distribution and conservation requirements are warranted for other microorganisms and soil organisms.


Assuntos
Micorrizas , Solo , Animais , Biodiversidade , Ecossistema , Florestas , Fungos , Humanos , Plantas , Microbiologia do Solo
12.
Opt Lett ; 47(23): 6073-6076, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37219175

RESUMO

Metasurfaces have made great progress in the past decade in generating various planar optical devices. However, most metasurfaces exhibit their functions in either reflection mode or transmission mode, with the other mode unutilized. In this work, we demonstrate switchable transmissive and reflective metadevices by combining metasurfaces with vanadium dioxide. The composite metasurface can work as a transmissive metadevice, with one function for vanadium dioxide in the insulating phase, and is changed to a reflective metadevice with another function for vanadium dioxide in the metallic phase. By carefully designing the structures, the metasurface can be switched from a transmissive metalens to a reflective vortex generator, or between a transmissive beam steering and a reflective quarter-wave plate through the phase transition of vanadium dioxide. The switchable transmissive and reflective metadevices have potential applications in imaging, communication, and information processing.

13.
BMC Cancer ; 22(1): 1128, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329394

RESUMO

BACKGROUND: Nutritional status and inflammation are closely associated with poor outcome in malignant tumors. However, the prognostic impact of postoperative in these variables on breast cancer (BC) remains inconclusive. We aimed to determine whether prognostic nutritional index (PNI), systemic immune-inflammation index (SII), neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) affect two long-term outcomes among patients after curative resection of BC. METHODS: We retrospectively reviewed 508 patients with BC treated with curative surgery between February 5, 2013 and May 26, 2020. All patients were divided into 3 groups based on tertiles (T1-T3) of PNI, SII, NLR, and PLR. The effects of four indexes on disease-free survival (DFS) and overall survival (OS) have been evaluated using Cox proportional hazards models and Kaplan-Meier method. RESULTS: Compared with PNI-lowest cases, patients with highest PNI showed significantly longer DFS (multivariate adjusted hazard ratio [HR] = 0.37, 95% confident interval [CI] 0.19-0.70, P for trend = 0.002), whereas higher PLR seemed to be marginally associated with poorer DFS (P for trend = 0.086 and 0.074, respectively). Subgroup analyses indicate the potential modification effects of family history of BC and radiotherapy on the prognosis value of PNI to DFS in BC patients (P for interaction = 0.004 and 0.025, respectively). In addition, the levels of three inflammatory indices, namely SII, NLR, and PLR might be positively related with increased age at diagnosis (all P for trend < 0.001). CONCLUSIONS: A high PNI was associated with better DFS, supporting its roles as prognostic parameters for patients with BC. The nutritional status and systemic immune may exert great effects on patient prognosis. Further studies are warrant to explore the prognosis value of PLR.


Assuntos
Neoplasias da Mama , Avaliação Nutricional , Humanos , Feminino , Prognóstico , Estudos Retrospectivos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Linfócitos/patologia , Neutrófilos/patologia , Inflamação/patologia
14.
Environ Sci Technol ; 56(20): 14338-14349, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36178372

RESUMO

We conducted experiments to determine whether bioaugmentation with aerobic, polychlorinated biphenyl (PCB)-degrading microorganisms can mitigate polychlorinated biphenyl (PCB) emissions from contaminated sediment to air. Paraburkholderia xenovorans strain LB400 was added to bioreactors containing PCB-contaminated site sediment. PCB mass in both the headspace and aqueous bioreactor compartments was measured using passive samplers over 35 days. Time-series measurements of all 209 PCB congeners revealed a 57% decrease in total PCB mass accumulated in the vapor phase of bioaugmented treatments relative to non-bioaugmented controls, on average. A comparative congener-specific analysis revealed preferential biodegradation of lower-chlorinated PCBs (LC-PCBs) by LB400. Release of the most abundant congener (PCB 4 [2,2'-dichlorobiphenyl]) decreased by over 90%. Simulations with a PCB reactive transport model closely aligned with experimental observations. We also evaluated the effect of the phytogenic biosurfactant, saponin, on PCB bioavailability and biodegradation by LB400. Time-series qPCR measurements of biphenyl dioxygenase (bphA) genes showed that saponin better maintained bphA abundance, compared to the saponin-free treatment. These findings indicate that an active population of bioaugmented, aerobic PCB-degrading microorganisms can effectively lower PCB emissions and may therefore contribute to minimizing PCB inhalation exposure in communities surrounding PCB-contaminated sites.


Assuntos
Dioxigenases , Bifenilos Policlorados , Biodegradação Ambiental , Hidroxilaminas , Bifenilos Policlorados/metabolismo
15.
Biomed Chromatogr ; 36(5): e5342, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35064586

RESUMO

Trifloxystrobin (TFS) is a widely used strobilurin fungicide and its residues accumulating in animal-derived food could result in potential harm to consumers. By optimization of extraction solvents and cleanup sorbents, a residue analysis method for TFS and its metabolite trifloxystrobin acid (TFSA) was established in milk, eggs and pork based on QuEChERS sample preparation and LC-MS/MS. The calibration curves exhibited good linearity with determination coefficients (R2 ) >0.9930 over the range of 0.5-250 ng/ml for both TFS and TFSA. The recoveries of the two analytes were 81-100% with RSD 3-10% and 76-96% with RSD 2-13%, respectively. The limit of quantification (LOQ) was 1 ng/g for both analytes. The milk, egg and pork samples, 30 each, were collected from the 30 main producing regions in China, and residues of TFS and TFSA were analyzed. The concentrations of both analytes were lower than the corresponding LOQs and maximum residue limits. Long-term dietary risk assessment showed that the hazard quotients were 0.001-0.003%, indicating an absence of unacceptable risks in milk, eggs and pork to the health of common consumers in China.


Assuntos
Resíduos de Praguicidas , Carne de Porco , Carne Vermelha , Acetatos , Animais , Cromatografia Líquida , Iminas , Leite/química , Resíduos de Praguicidas/análise , Carne Vermelha/análise , Medição de Risco , Estrobilurinas/análise , Suínos , Espectrometria de Massas em Tandem
16.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(3): 318-322, 2022 May 30.
Artigo em Zh | MEDLINE | ID: mdl-35678444

RESUMO

In the perspective of technical evaluation, the pre-marketing regulatory requirements of allergen detection reagents in China, America, European Union were compared, and the regulatory risks and performance requirements of this product were analyzed based on the monitoring of post-marketing adverse events, reference standards and domestic and foreign regulatory documents. In view of the "neck-stuck" problems such as the difficulty of clinical trials, the difficulty of finding comparable contrast reagents and the lack of clinical diagnostic gold standards, this paper discusses and gives regulatory suggestions, with a view to providing technical reference for product R&D, production, evaluation, approval and supervision in this field.


Assuntos
Alérgenos , Marketing , União Europeia , Indicadores e Reagentes , Padrões de Referência
17.
Opt Express ; 29(5): 7494-7503, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33726249

RESUMO

Wave plates based on metasurfaces have attracted intensive attention over the past decade owing to their compactness and design flexibility. Although various wave plates have been designed, their working wavelengths are fixed once they are made. Here we present a study on tunable wave plates based on phase-change metasurfaces made of Ge2Sb2Te5 nanopillar structures. The Ge2Sb2Te5 nanopillars can work as a high-efficiency transmissive half- or quarter-wave plate depending on their structural parameters. The working wavelength of wave plate can be tuned via the phase transition of Ge2Sb2Te5. Moreover, the polarization state of the transmitted light at a fixed wavelength can be modified by changing the crystallinity of Ge2Sb2Te5. The features suggest that tunable wave plates may have applications in optical modulators, molecular detection, and polarimetric imaging.

18.
J Sep Sci ; 44(20): 3860-3869, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34384003

RESUMO

Methoxyfenozide and metaflumizone are insecticides used on Chinese broccoli to prevent insects and increase yield. However, the residues are potentially harmful to the environment and consumers. In this study, the quick, easy, cheap, effective, rugged, safe method with high-performance liquid chromatography with tandem mass spectrometry was modified and validated for determination of methoxyfenozide and metaflumizone in Chinese broccoli. The clean-up efficiency of different sorbents including C18 , primary secondary amine, graphitized carbon black, and carbon nanofiber was compared. Recoveries of the validated method were 71.8-94.6% with relative standard deviations of 1.5-3.2% and the limits of quantification were 0.01 and 0.005 mg/kg for methoxyfenozide and metaflumizone, respectively. A storage stability test showed almost no degradation of methoxyfenozide in Chinese broccoli, however, the degradation rate of metaflumizone was 22.9% after 10-wk storage at -20°C. In field trials in four producing regions, the dissipation of both methoxyfenozide and metaflumizone in Chinese broccoli was fast, with half-lives of only 1.0-5.1 and 0.7-2.5 days, respectively. Terminal residues after application of the two pesticides were all below 1.0 mg/kg after 5 days.


Assuntos
Brassica/química , Hidrazinas/análise , Hormônios Juvenis/análise , Resíduos de Praguicidas/análise , Semicarbazonas/análise , China , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
19.
Ecotoxicol Environ Saf ; 207: 111272, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32927162

RESUMO

Tobacco smoke is a common global environmental pollutant. Maternal tobacco smoke/nicotine exposure has long-term toxic effects on immune organs. We previously found that prenatal nicotine exposure (PNE)-induced programmed immune diseases caused by fetal thymic hypoplasia, but the mechanism still unknown. Autophagy has important functions in maintaining thymopoiesis, whether autophagy was involved in PNE-inhibited fetal thymocytes development is also obscure. Therefore, this study aimed to investigate how nicotine changed the development of fetal thymocytes from the perspective of autophagy in vivo and in vitro. PNE model was established by 3 mg/kg nicotine administration in Balb/c mice from gestational day 9 to 18. The results showed that PNE reduced the percentage and absolute number of CD69-CD4+SP cells, suggesting a block of fetal thymocytes mature. PNE promoted autophagosome formation, autophagy related proteins (Beclin1, LC3I/II) expression, and upregulated α7 nAChR as well as AMPK phosphorylation in fetal thymus. Moreover, PNE promoted Bcl10 degradation via autophagy-mediated proteolysis and inhibited p65 activation, blocking the transition of thymocytes between the DP to SP stage. Further, primary thymocytes were treated with nicotine in vitro and showed induced autophagy in a dose- and time-dependent manner. In addition, nicotine-inhibited CD69-CD4+SP cells and the Bcl10/p-p65 pathway have been reversed by an autophagy inhibitor. The α7 nAChR specific antagonist abrogated nicotine-induced AMPK phosphorylation and autophagy initiation. In conclusion, our findings showed that PNE repressed the Bcl10/p-p65 development pathway of CD4+SP cells by triggering autophagy, and illuminated the developmental origin mechanism of programmed immune diseases in PNE offspring.


Assuntos
Substâncias Perigosas/toxicidade , Nicotina/toxicidade , Timócitos/fisiologia , Animais , Autofagia/efeitos dos fármacos , Proteína 10 de Linfoma CCL de Células B , Proteína Beclina-1 , Feminino , Feto , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Timócitos/efeitos dos fármacos , Timócitos/imunologia , Vitaminas
20.
Entropy (Basel) ; 23(8)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34441150

RESUMO

Measurement-device-independent quantum key distribution (MDI-QKD) protocol has high practical value. Satellite-based links are useful to build long-distance quantum communication network. The model of satellite-based links for MDI-QKD was proposed but it lacks practicality. This work further analyzes the performance of it. First, MDI-QKD and satellite-based links model are introduced. Then considering the operation of the satellite the performance of their combination is studied under different weather conditions. The results may provide important references for combination of optical-fiber-based links on the ground and satellite-based links in space, which is helpful for large-scale quantum communication network.

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