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In this study, we measured 15 common organophosphate flame retardants (OPFRs) in six categories of tea samples across China. OPFRs were found in all the tea samples, with the total concentrations of OPFRs (∑OPFRs) at 3.44-432 ng/g [geometric mean (GM): 17.6 ng/g]. Triphenyl phosphate (TPhP) was the dominant OPFR, accounting for 39.0-76.2% of ∑OPFRs across all tea categories. The potential factors influencing the residual OPFRs in tea were thoroughly examined, including the agricultural environment, fermentation, and packaging of teas. Tea packaging materials (TPMs) were then identified as the primary sources of OPFRs in teas. The migration test revealed that OPFRs with lower molecular weights and log Kow values exhibited a higher propensity for facilitating the migration of OPFRs from TPMs to teas. The estimated daily intakes of OPFRs from teas were relatively higher for the general populations in Mauritania, Gambia, Togo, Morocco, and Senegal (3.18-9.79 ng/kg bw/day) than China (3.12 ng/kg bw/day). The health risks arising from OPFRs in Chinese teas were minor. This study established a baseline concentration and demonstrated the contamination sources of OPFRs in Chinese tea for the first time, with an emphasis on enhancing the hygiene standards for TPMs.
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Retardadores de Chama , Organofosfatos , Chá , Retardadores de Chama/análise , Chá/química , China , Medição de Risco , Embalagem de Alimentos , Humanos , Contaminação de AlimentosRESUMO
The prevalence and distribution of chlorinated paraffins (CPs) have been extensively studied in various matrices and organisms; however, there is a lack of information about insects, particularly in honeybees. To address this gap, we studied young honeybee workers exposed to short- and medium-chain CPs (SCCPs and MCCPs) at an environmentally relevant concentration of 10 mg/L for 7 days, followed by a 7-day elimination period. Results indicated that CPs could transfer into the head after oral consumption and SCCPs and MCCPs exhibited clear bioaccumulation trends: midgut > hindgut > head. An evaluation of congener group distribution patterns demonstrated that the dominant congener groups in all target tissues were C11-13Cl7-8 and C14Cl7-8 for SCCPs and MCCPs, respectively, consistent with the treated CP standards. In honeybees, a significant negative relationship was observed for the log concentration of MCCP congener groups and their logâ¯KOW, but not with their logâ¯KOA. Conversely, no such correlation was found for SCCPs. These findings suggest that honeybees have a high potential to bioaccumulate MCCPs, particularly those with a low logâ¯KOW, and exhibit weak selectivity for SCCPs.
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Parafina , Animais , Abelhas , Parafina/metabolismo , Hidrocarbonetos Clorados/metabolismo , Administração OralRESUMO
Chlorinated paraffins (CPs) are hazardous to humans, and dietary intake acts as the primary pathway for human exposure to CPs. Takeout food is popular worldwide, but the presence of CPs in takeout food and its packaging is unclear. In this study, the concentrations and distributions of short- and median-chain CPs (SCCPs and MCCPs, respectively) were measured in 97 samples of four categories of takeout food and 33 samples of three types of takeout packaging. The SCCP and MCCP median concentrations for the takeout food samples were 248 and 339, 77.2 and 98.2, 118 and 258, 42.9 and 64.4 ng/g wet weight in meat, starch, half meat/half starch, and vegetables, respectively. Takeout food contained higher concentrations of SCCPs than MCCPs. The dominant SCCP and MCCP congener groups in takeout food were C10Cl6-7 and C14Cl7-8, respectively. The CP concentrations in takeout food were lower than those in packaging. The SCCP and MCCP median concentrations, respectively, in packaging were 9750 and 245 ng/g in polypropylene, 2830 and 135 ng/g in paper, and 2060 and 119 ng/g in aluminum foil. The concentrations of SCCPs and MCCPs were comparable in aluminum foil, whereas the concentrations of SCCPs were higher than those of MCCPs in polypropylene and paper. Correlations between CP concentrations in the takeout food and packaging indicated that CPs in packaging were potentially an important source of CPs in the takeout food. A dietary exposure risk assessment showed the takeout food posed a low risk for human exposure to CPs; however, high-frequency consumption may pose a health risk. This study clarified the current contamination situation in takeout food in Beijing, China. The resulting data could be used to prevent human exposure to CPs through dietary intake and to facilitate the market's control over the quality of takeout food.
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Exposição Dietética , Contaminação de Alimentos , Embalagem de Alimentos , Parafina , Exposição Dietética/análise , Contaminação de Alimentos/análise , Parafina/análise , Humanos , Medição de Risco , Pequim , Hidrocarbonetos Clorados/análise , ChinaRESUMO
Chlorinated paraffins (CPs) in poultry feed and the farm environment might bioaccumulate in poultry eggs. Unlike chickens, which are mostly raised in cages, ducks are commonly raised free range. This would expose ducks to CPs in the environment. However, information on the presence of CPs on duck farms is scarce. In the present study, samples of duck eggs, duck feathers, poultry feed, and soil were collected from 25 duck farms in South China. Forty-eight congener groups of short- and medium-chain CPs (SCCPs and MCCPs) were detected in the samples. Interestingly, relatively high concentrations of SCCPs and MCCPs were found in the duck feathers. The median concentrations of SCCPs and MCCPs in the duck eggs, feathers, feed and soil were: 46 and 18 ng/g wet weight, 2460 and 992 ng/g, 103 and 47 ng/g, and 24 and 10 ng/g dry weight, respectively. The dominant groups of SCCPs and MCCPs were C10Cl6-7 and C14Cl7-8, respectively. The close relationship between duck feathers and poultry feed indicated that the duck feathers might act as a bioindicator for the exposure of ducks to CPs. The margin of exposure approach was used to assess the health risk, with the results showing that the consumption of duck eggs posed a low risk to different age groups from exposure to SCCPs and MCCPs.
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Patos , Hidrocarbonetos Clorados , Animais , Parafina/análise , Fazendas , Exposição Dietética , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise , Galinhas , China , SoloRESUMO
PURPOSE: To evaluate the efficacy and safety outcomes of our newly developed skewer technique in the management of lens dislocation. METHODS: A total of 21 eyes with lens dislocation were treated with this surgical technique. We focused on best-corrected visual acuity (BCVA), intraocular pressure, and complications of retinal damage at 3 months post-surgery. RESULTS: The mean age of the patients was 60.20 ± 10.73 (range: 41-85) years, and the average axial length was 25.40 ± 2.35 (range: 22.30-32.35) mm. The BCVA at 3 months post-surgery showed a significant improvement compared to preoperative measurements. No intraoperative or postoperative retinal damage occurred in any eyes treated with this new technique. CONCLUSION: The "skewer" technique we developed is an innovative solution for addressing lens dislocation. Phacoemulsification can be performed in the anterior chamber utilizing a light guide to control the position and movement of the lens. This approach eliminates the need for perfluorocarbon liquid or extensive pars plana scleral sclerotomy. Based on postoperative outcomes from a series of patients who underwent this procedure, the technique is highly safe and feasible.
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PURPOSE: To summarize the causes of retinal arterial microaneurysm combined with branch retinal artery occlusion. METHODS: The case reports of retinal arterial microaneurysm combined with branch retinal artery occlusion were searched in PubMed, Web of Science, and CNKI databases before May 1, 2024. A total of nine participants from nine case reports were included to analyze factors leading to complications. RESULTS: The reasons for this complication are as follows: complications during photocoagulation therapy. Intraretinal hemorrhage and exudation result in compression of adjacent or distal arteries, resulting in branch retinal artery occlusion. Embolus dislodgement or intraarterial embolus formation can block the artery, damage the wall, and provide conditions for the development of retinal arterial microaneurysm. In addition, it is necessary to be alert to the optic disk macroaneurysm, if hemorrhage or embolus formation in the macroaneurysm will affect the blood supply of the downstream artery, affecting a large range of the retina. CONCLUSION: Based on the review of case reports, we found that retinal arterial microaneurysm and branch retinal artery occlusion can cause each other. Acute vision loss can result when a complication occurs. In addition, retinal vascular diseases can reflect the whole body, suggesting that ophthalmologists need to pay attention not only to the patient's fundus but also to the patient's systemic diseases.
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Macroaneurisma Arterial Retiniano , Oclusão da Artéria Retiniana , Artéria Retiniana , Humanos , Oclusão da Artéria Retiniana/diagnóstico , Oclusão da Artéria Retiniana/etiologia , Macroaneurisma Arterial Retiniano/diagnóstico , Macroaneurisma Arterial Retiniano/complicações , Artéria Retiniana/diagnóstico por imagem , Angiofluoresceinografia/métodos , Fundo de Olho , Acuidade Visual , Hemorragia Retiniana/diagnóstico , Hemorragia Retiniana/etiologia , Tomografia de Coerência ÓpticaRESUMO
BACKGROUND: Pulmonary tuberculosis is a chronic infectious disease of the respiratory system. It is still one of the leading causes of death from a single infectious disease, but it has been stuck in the study of a single pathogen. Recent studies have shown that many diseases are associated with disruption of the native microbiota. In this study we investigated the occurrence of tuberculosis and the correlation between drug resistance and respiratory flora. High-throughput 16 S rRNA gene sequencing was used to characterize the respiratory microbiota composition of 30 tuberculosis (TB) affected patients and compared with 30 healthy (H) controls. According to their Gene Xpert results, 30 pulmonary tuberculosis patients were divided into 12 persons in the drug-sensitive group (DS0) and 18 persons in the drug-resistant group (DR0). The microbial flora of the two were compared with the H group. RESULTS: The data generated by sequencing showed that Firmicutes, Proteus, Bacteroides, Actinomyces and Fusobacterium were the five main bacterial phyla detected, and they constituted more than 96% of the microbial community. The relative abundances of Fusobacterium, Haemophilus, Porphyromonas, Neisseria, TM7, Spirochetes, SR1, and Tenericutes in the TB group was lower than that of the H group, and Granulicatella was higher than the H group. The PcoA diagrams of the two groups had obvious clustering differences. The Alpha diversity of the TB group was lower than that of the H group, and the Beta diversity was higher than that of the H group (P < 0.05). The relative abundance of Streptococcus in the DS0 group was significantly higher than that in the DR0 group (P < 0.05). CONCLUSION: Pulmonary tuberculosis can cause disorders of the respiratory tract microbial flora, in which the relative abundance of Streptococcus was significantly different between rifampicin-sensitive and rifampicin-resistant patients.
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Microbiota , Tuberculose Pulmonar , Humanos , Rifampina/farmacologia , Tuberculose Pulmonar/tratamento farmacológico , Sistema Respiratório , FusobacteriumRESUMO
BACKGROUND: Urban green open space is a valuable resource for physical activities of urban inhabitants and has the potential to reduce chronic illness and improve health. Research on the relationships between green open space and physical activity is incomplete and limited in China. Thus, the study examines how the urban green open space contributes to physical activity. METHODS: A questionnaire was designed based on the social ecology theory to investigate the physical activity of 513 residents in urban green open space. We use the time and frequency of residents exercising in urban green space to measure physical activity, and use the factor analysis to synthesize a large number of original factors (i.e., infrastructure, safety, accessibility, landscape quality, and space environment) into relatively few composite indicators. Based on the collected data of the cross-sectional population, the Order Probit regression model was constructed to analyze how urban green open space affects the residents' physical activity from the perspective of social ecology. RESULTS: â in community factors: accessibility is significantly positive correlation with residents' physical activity, and there is no significant correlation between safety and physical activity; â¡in natural factors: space environment and landscape quality are not significantly correlated with residents' physical activity; ⢠in built environmental factors: infrastructures, the area of green space, the size of open space, and entertainment facilities are significantly correlated to residents' activity. Basketball courts, volleyball courts, swimming pools, and sports equipment will promote physical activity; ⣠apart from the attributes of green open space, other factors are significantly correlated to physical activity in the green open space, e.g. having a companion. CONCLUSIONS: Urban green open space plays an important role in promoting physical activity especially among the women and the old, and improving the attributes (such as accessibility, infrastructures, the area of green space, the size of open space and entertainment facilities) of the urban green open space and trying to set up group sports proper to play with companion (like "square dancing" and "Tai Chi") can promote Chinese residents' physical activity so as to improve public health. The results are significant to facilitate environment health.
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Planejamento Ambiental/estatística & dados numéricos , Exercício Físico , Parques Recreativos/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adulto , China , Estudos Transversais , Feminino , Humanos , Masculino , Meio Social , Teoria Social , Inquéritos e QuestionáriosRESUMO
This paper aimed to build up a sensitive CE method for the analysis of tetracyclines (TCs) antibiotics (including tetracycline, chlorotetracycline, oxytetracycline, and doxycycline) with conventional UV detection. Here, the large volume sample stacking was applied to achieve in capillary preconcentration of the targets. To achieve large volume sample stacking, the essential step was a large volume of sample (around 83.3% of total capillary length from inlet to detection window) hydrodynamically loaded. Then, the reserved voltage was added in order to push the sample matrix out of the capillary. Due to different pH between sample solution (pH 4.6) and BGE (pH 11.0), the cationic TCs would turn into negatively charged while the sample matrix was removing from the capillary. Finally, the anionic TCs were stacked at the inlet for the subsequent separation. Although the loss of sample existed during their charge transformation, the LODs could be improved around 40 times than that obtained by normal hydrodynamic injection CE method. Here, the LODs were in the range of 8.1-14.5 µg/L, around 10 ppb that close to the level by electrochemiluminescence or laser-induced fluorescence detection of TCs by CE. The precision was characterized by RSDs of migration times and peak areas, which were in the range of 0.19-0.24% and 0.97-2.54%, respectively. The recoveries of the developed method were in the range of 95-112% by spiking TCs in the tap water. The proposed inline preconcentration CE method could be a simple, speed, and sensitive method for the quantitative analysis of TCs.
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Eletroforese Capilar/métodos , Tetraciclinas/análise , Cátions , Concentração de Íons de Hidrogênio , Limite de Detecção , Reprodutibilidade dos Testes , Tetraciclinas/química , Tetraciclinas/isolamento & purificação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificaçãoRESUMO
Porcine deltacoronavirus (PDCoV) is an emerging porcine enteropathogenic coronavirus that causes acute watery diarrhoea in piglets, resulting in significant economic losses to the global swine industry. However, the underlying mechanism of PDCoV infection is not well defined, which seriously hinders the development of effective drugs and vaccines. Integrins (ITG) are heterodimeric transmembrane glycoproteins that play important roles in the life cycle of many viruses. In the current study, the viral entry pathways of PDCoV were explored and the role of ITGαVß3 was investigated during PDCoV infection. Our results showed that the lysosomal acidification inhibitor bafilomycin-A1 (Baf-A1) significantly reduced PDCoV infection, while exogenous protease facilitated PDCoV infection and even allowed PDCoV entry to bypass the endosomal pathway, suggesting PDCoV entry into cells via the endocytic pathway and the exogenous protease-mediated pathway simultaneously. Furthermore, ITGαVß3 was identified to be involved in PDCoV infection, especially during viral entry stages. PDCoV infection triggers the activation of the focal adhesion kinase (FAK)-phosphatidylinositol 3-kinase (PI3K)-serine/threonine-specific protein kinase (AKT) signalling pathway, and this activation is ITGαVß3-dependent, suggesting that the activation of the FAK-PI3K-AKT signalling pathway during PDCoV infection is mediated by ITGαVß3. Our results further demonstrated that PDCoV infection induced the expression of inflammatory cytokines, which was mediated by activation of the ITGαVß3-FAK-PI3K-AKT-nuclear transcription factor-κB (NF-κB) signalling pathway. Overall, the results revealed that ITGαVß3 is an essential host factor for PDCoV infection and can serve as a supplementary receptor to facilitate PDCoV infection, which can help us to explore the molecular mechanism of PDCoV infection.
Identifying the host factors required for entry will be helpful in uncovering the pathogenesis mechanisms and developing antivirals against the emerging coronavirus porcine deltacoronavirus (PDCoV). Herein, we revealed that PDCoV enters cells via the endocytic and exogenous protease-mediated pathways simultaneously. Integrins (ITG) αVß3 is a host factor required for PDCoV infection, especially during virus adhesion, invasion, and release. Most importantly, PDCoV promotes viral infection by activating the ITGαVß3-focal adhesion kinase (FAK)-phosphatidylinositol 3-kinase (PI3K)-serine/threonine-specific protein kinase (AKT) signalling pathway and induces inflammation by activating the ITGαVß3-FAK-PI3K-AKT-NF-κB signalling pathway. Overall, this is the first study to identify ITGαVß3 as an essential factor for PDCoV infection, which can help us to confirm the molecular regulatory mechanism and provide a comprehensive resource for PDCoV infection.
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Infecções por Coronavirus , Deltacoronavirus , Integrina alfaVbeta3 , NF-kappa B , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Doenças dos Suínos , Animais , Integrina alfaVbeta3/metabolismo , Integrina alfaVbeta3/genética , Suínos , NF-kappa B/metabolismo , Doenças dos Suínos/virologia , Doenças dos Suínos/imunologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Deltacoronavirus/genética , Infecções por Coronavirus/virologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/veterinária , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/genética , Internalização do Vírus , Inflamação , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/genéticaRESUMO
Short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) are hazardous industrial chemicals that tend to bioaccumulate in animal-derived foodstuffs through the food supply chain. However, the lack of reliable noninvasive bioindicators hinders the monitoring of farm animal exposure to CPs. In this study, 169 cattle hair samples were collected from beef cattle farms in six Chinese provinces, with further beef, feed, and soil samples being collected in Hebei province. Geographical differences in CP concentrations were observed in the hair samples, and CP concentrations in samples collected from Hebei province decreased in the following order: hair > feed > beef > soil. C10-11Cl6-7 and C14Cl7-8 were the predominant SCCPs and MCCPs, respectively, in all the hair, beef, feed, and soil samples. CP concentrations in hair samples significantly correlated with those in beef, feed, and soil samples, indicating that hair can be used as a bioindicator of cattle exposure to CPs. The possible health risks associated with exposure to CPs through beef consumption, especially for children and high-volume beef consumers, should be further investigated.
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Cabelo , Parafina , Animais , Bovinos , Cabelo/química , Parafina/análise , China , Hidrocarbonetos Clorados/análise , Ração Animal/análise , Monitoramento Ambiental/métodos , Fazendas , Poluentes do Solo/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análiseRESUMO
A fluorescent probe based on salicylate modified layered double hydroxide (LDH-SA) is presented, enabling the swift sequential detection of Al3+, fosetyl-Al and glyphosate in aqueous environment. The probe was synthesized using a simple co-precipitation procedure, and its properties and synthesis conditions were thoroughly characterized and optimized. A unique "off-on-off" fluorescent response was observed when the probe sequentially interacted with Al3+ and glyphosate, and the detection method based on this phenomenon was established. The limits of detection for Al3+ and glyphosate were determined as 0.03 µmol/L and 0.03 mg/L, respectively, with rapid detection periods of one minute and four minutes. The LDH-SA/Al3+ complex requires Al3+ to generate a chelation-gathered fluorescence effect, which is the mechanism by which it quenches LDH-SA. This is possible due to the inhibition of excited-state intramolecular proton transfer and photoinduced electron transfer processes within LDH-SA after incorporating Al3+. Upon interaction with glyphosate, competitive complexation between glyphosate and Al3+ is initiated, which leads to a recovery of the fluorescence spectrum of LDH-SA and demonstrating the "off-on-off" behavior. An "INHIBIT" logic gate system was devised utilizing the response, indicating potential applications in fluorescence-based devices. Such a rapid, sequential detection capacity is impressive. It attests to the utility of LDH-SA as a probe for Al3+ or glyphosate, and suggests promise for applications in pollutant analysis or environmental monitoring applications.
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Chlorinated paraffins (CPs) are industrial chemicals that have potential adverse effects in the environment and on human health. This study investigated CPs in apiary environment, honeybees, and bee products from two rural areas of Beijing, China. The median concentrations of short-chain CPs (SCCPs) and medium-chain CPs (MCCPs) were 22 and 1.6 ng/m3 in the ambient air, 1350 and 708 ng/g dry mass (dw) in bees, 1050 and 427 ng/g dw in flowers, 37 and 54 ng/g in honey, 78 and 53 ng/g dw in bee pollen, 36 and 30 ng/g dw in soil, and 293 and 319 ng/g dw in bee wax. C10Cl6-7 and C14Cl7-8 dominated SCCPs and MCCPs in these samples, respectively. The concentrations and distributions of CPs in samples from apiaries located in the two regions varied. Long-range transportation of air masses was identified as an important source of CPs in apiaries. A close relationship between CPs in bees and the apiary environment indicated that bees could act as bioindicators for CP contamination in the environment. A human health risk assessment found that there were low risks for adults and children exposed to CPs through consumption of honey and pollen from the studied regions.
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Hidrocarbonetos Clorados , Parafina , Criança , Abelhas , Humanos , Animais , Parafina/análise , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , China , PequimRESUMO
Fish are an important source of human dietary exposure to polychlorinated naphthalenes (PCNs). The occurrence and sources of PCNs in different species of freshwater fish are unknown, and few studies have assessed human exposure risks to PCNs through freshwater fish. In this study, 140 freshwater fish samples from 10 species were collected from Beijing markets, China. The Σ75CNs concentration range in the fish was 20.7-1310 pg/g wet weight (ww). The highest median Σ75PCNs concentration (80.4 pg/g ww) was found in mandarin fish (Siniperca chuatsi), and the lowest (29.6 pg/g ww) in snakehead (Channa argus). Di- and tri-CNs were the dominant PCN homologues with contributions of 35.3 % and 30.8 %, respectively. Unintentionally produced PCNs from metal smelting might be the source of PCN contamination in freshwater fish. The cooking temperature and time did not significantly affect the PCN concentrations in fish or the PCN homologue profiles. The highest toxic equivalent (TEQ) value was observed in sturgeon (Acipenser sinensis), followed by mandarin fish. Hexa-CNs were the most abundant homologue for the PCN TEQs. A risk assessment indicated that the dietary exposure risks for local residents to PCNs through freshwater fish were low. However, the relatively high concentrations of PCNs in the samples deserve attention to avoid PCNs exposure risks for groups with high fish consumption rates. Furthermore, freshwater fish likely contain a mixture of contaminants including dioxin and furans which also display a similar mode of toxicity as the PCNs and could enhance the risk to fish consumers.
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Naftalenos , Dibenzodioxinas Policloradas , Animais , Humanos , Pequim , Naftalenos/análise , Dibenzodioxinas Policloradas/análise , Água Doce , Medição de Risco , Monitoramento AmbientalRESUMO
Acquired resistance to Taxol (TAX) contributes to clinical treatment failure and significantly reduces the survival rate of patients. The present study aimed to explore the effects of exosomal microRNA (miR)-187-5p on TAX resistance in breast cancer cells and its underlying mechanisms. Exosomes were isolated from MCF-7 and TAX-resistant MCF-7/TAX cells, and the miR-187-5p and miR-106a-3p levels of the cells and exosomes were determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Next, MCF-7 cells were treated with TAX for 48 h and either treated with exosomes or transfected with miR-187-5p mimics. Cell viability, apoptosis, migration, invasion and colony formation were determined using Cell Counting Kit-8, flow cytometry, Transwell and colony formation assays, and the expression levels of associated genes and proteins were detected by RT-qPCR and western blotting, respectively. Finally, a dual-luciferase reporter gene assay was performed to confirm the target of miR-187-5p. The results showed that miR-187-5p expression levels increased significantly in TAX-resistant MCF-7 cells and exosomes compared with normal MCF-7 cells and exosomes (P<0.05). However, miR-106a-3p was not detected in the cells or exosomes. Therefore, miR-187-5p was selected for subsequent experiments. A series of cell assays showed that TAX inhibited the viability, migration, invasion and colony formation of MCF-7 cells and promoted their apoptosis; however, these changes were reversed by resistant cell exosomes and miR-187-5p mimics. Additionally, TAX significantly upregulated ABCD2 and downregulated ß-catenin, c-Myc and cyclin D1, whereas resistant exosomes and miR-187-5p mimics reversed the TAX-induced changes in expression. Finally, ABCD2 was confirmed to directly bind with miR-187-5p. It may be concluded that TAX-resistant cell-derived exosomes delivering miR-187-5p may affect the growth of TAX-induced breast cancer cells by targeting ABCD2 and c-Myc/Wnt/ß-catenin signaling.
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In this work, we proposed a method of extracting feature parameters for deep neural network prediction based on the vectorgraph storage format, which can be applied to the design of electromagnetic metamaterials with sandwich structures. Compared to current methods of manually extracting feature parameters, this method can automatically and precisely extract the feature parameters of arbitrary two-dimensional surface patterns of the sandwich structure. The position and size of surface patterns can be freely defined, and the surface patterns can be easily scaled, rotated, translated, or transformed in other ways. Compared to the pixel graph feature extraction method, this method can adapt to very complex surface pattern design in a more efficient way. And the response band can be easily shifted by scaling the designed surface pattern. To illustrate and verify the method, a 7-layer deep neural network was built to design a metamaterial broadband polarization converter. Prototype samples were fabricated and tested to verify the accuracy of the prediction results. In general, the method is potentially applicable to the design of different kinds of sandwich-structure metamaterials, with different functions and in different frequency bands.
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Porewater is the primary carrier of sediment nitrogen and a crucial source of overlying water nitrogen; its separation thus is essential for restraining nitrogen release from sediment to overlying water. We developed a novel device using electrokinetic geosynthetics to drain porewater with nitrogen and restrain nitrogen release. A batch experiment lasted 1120 h (about 47 days) was conducted with 20 cm depth of overlying water under three conditions, i.e., undrained at 0 V/cm voltage gradient (control), drained at 0 V/cm, and drained at 0.5 V/cm. Under the pulsed direct current, once porewater drained, overlying water replenished sediment pore space and supplied porewater. Along with porewater drainage, sediment nitrogen concentration was reduced by 11%-30%, decreasing nitrogen release from sediment to overlying water from 83 mg/m2 in the first 100 h to -95 mg/m2 after about 600 h. Processes such as electroosmosis, electromigration, and redox reaction contributed to the restraint on nitrogen release. This research revealed the potentiality of applying electrokinetic geosynthetics to in-situ restraint on sediment nitrogen release in eutrophic waterbodies such as fishponds.
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Nitrogênio , Poluentes Químicos da Água , Sedimentos Geológicos , Nitrogênio/análise , Fósforo , Água , Poluentes Químicos da Água/análiseRESUMO
Chlorinated paraffins (CPs) have been found to occur ubiquitously in foodstuff of both animal and plant origin. However, limited information is available on the content of CPs in green tea, one of the most commonly consumed beverages worldwide. Herein, 107 commercial green tea samples originating from 11 provinces of China, were collected to study the occurrence of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs, respectively). The concentration of SCCPs in all green tea samples ranged from 4.99 to 717 ng/g (mean: 55.7 ng/g), while MCCPs ranged from 2.55 to 543 ng/g (mean: 33.5 ng/g). CP profiles in green tea samples from different provinces exhibited no regional differences. To identify the potential sources of CPs in green tea, 19 tea packaging samples were collected and analyzed, showing that SCCPs and MCCPs existed at much higher concentrations in the tea packaging material than in the teas. Migration tests indicated that CPs could migrate from packaging into teas during storage, with the migration velocity and efficiency of SCCPs being higher than MCCPs.
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Hidrocarbonetos Clorados , Parafina , Animais , China , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Parafina/análise , CháRESUMO
In recent years, China had released various environmental regulations in order to respond climate change and corresponding environmental issues. However, due to imbalanced economic development and industrial structure, different Chinese regions had different enforcement levels on environmental regulations, which led to the regional transfer of pollution-intensive industries. To study the regional disparities on carbon emission transfer, this paper used the propensity score matching-difference in differences method (hereinafter abbreviated as "PSM-DID") to evaluate the mechanism between carbon trading pilot policies and the transfer of pollution-intensive industries. Panel data on 30 Chinese provinces were used to test the validity of the "pollution haven hypothesis," covering the period of 2010-2018. The empirical results showed that under the constraints of established environmental regulation, the pilot policy promoted the transfer of pollution-intensive industries to a certain extent and verified the "pollution haven hypothesis"; the proportion of the secondary sector and energy industry in the pilot areas had been reduced after the pilot policy; on the contrary, the technical level and the economic development level of the pilot provinces and cities had been further improved.
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Carbono , Gases de Efeito Estufa , Carbono/análise , Dióxido de Carbono/análise , China , Desenvolvimento Econômico , IndústriasRESUMO
In this study, a novel FONs-based sensor P-M(w) was synthesized using 1-Pyrenecarboxaldehyde and L-methionine through facile hydrothermal strategy. The fluorescence emission peaks of the acquired P-M(w) would show specific changes after the addition of Hg2+ due to interfering the PET process and inducing nano-structure conformational rigidification of P-M(w). Notably, the water-soluble FONs-based sensor was firstly used to detect Hg2+ in tea samples providing a new material choice for the fluorescence sensor construction of metal ion detection. Besides, the qualitative and quantitative analysis of Hg2+ could be carried out with P-M (w) at a very low concentration (1 µg/mL) meaning that the acquired P-M(w) synthesized by few grams of reactants may satisfy the detection of approximate fifty thousand samples.