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1.
Chemosphere ; 249: 126449, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32208217

RESUMO

Influence of floc breakage and re-growth on the release of natural dissolved organic matter (DOM) and dissolved Al was explored. Results indicated that Al species including monomeric species (Ala), medium polymer species (Alb), and colloidal or solid species (Alc) in polyaluminum chlorides (PACls) played significant role. At lower doses ranged from 5 to 20 mg/L, floc breakage damaged Ala-NOM bonds for AlCl3, causing obvious release of DOM and dissolved Al. After re-growth, dissolved Al mainly connected with broken flocs, rather than released DOM. Thus, after re-growth, DOM release was still remarkable, but additional removal of dissolved Al was observed. At higher doses above 20 mg/L, more Ala transformed to Alb and Alc. Due to the enmeshment effect induced by Alc coagulation, fewer DOM and dissolved Al were released after breakage, and additional removal of DOM and dissolved Al were attained after re-growth. For PAClAl13 which mainly contained Alb, at optimal dose, floc breakage generated the most severe release of DOM and dissolved Al, while the result after re-growth was just reverse. This was ascribed to stronger charge neutralization ability of Alb. Furthermore, the influence of floc breakage and re-growth on DOM and dissolved Al for PAClC was similar to that for AlCl3. The reason was fully analyzed in this research. This study may give further indication regarding reaction mechanisms of floc breakage and re-growth for PACls.

2.
J Radiat Res ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32211858

RESUMO

Ataxia-telangiectasia (AT) and MRE11-defective Ataxia-telangiectasia-like disorder (ATLD) patients show progressive cerebellar ataxia. ATM, mutated in AT, can be activated in response to oxidative stress as well as DNA damage, which could be linked to disease-related neurodegeneration. However, the role of MRE11 in oxidative stress responses has been elusive. Here, we showed that MRE11 could participate in ATM activation during oxidative stress in an NBS1/RAD50-independent manner. Importantly, MRE11 was indispensable for ATM activation. We identified FXR1 as a novel MRE11-binding partner by mass spectrometry. We confirmed that FXR1 could bind with MRE11 and showed that both localize to the cytoplasm. Notably, MRE11 and FXR1 partly localize to the mitochondria, which are the major source of cytoplasmic reactive oxygen species (ROS). The contribution of FXR1 to DNA double-strand break damage responses seemed minor and limited to HR repair, considering that depletion of FXR1 perturbed chromatin association of homologous recombination repair factors and sensitized cells to camptothecin. During oxidative stress, depletion of FXR1 by siRNA reduced oxidative stress responses and increased the sensitivity to pyocyanin, a mitochondrial ROS inducer. Collectively, our findings suggest that MRE11 and FXR1 might contribute to cellular defense against mitochondrial ROS as a cytoplasmic complex.

3.
Cancer Manag Res ; 12: 1241-1251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32110098

RESUMO

Purpose: Bladder Carcinoma (BC) is a malignant carcinoma with a high incidence in masculinity. We preliminarily researched the efficacy and mechanism of matrine (MAT) in T24 and 5637 cells. Patients and Methods: CCK-8, flow cytometry, migration and invasion means were adopted to detect cell viability, apoptosis, migratory and invasive potentials. Moreover, LINC00472 expression was changed via transfection assays and was tested by RT-qPCR. Western blot was used for investigating the levels of CyclinD1, p53, Bcl-2, Bax, pro-Caspase-3, Cleaved-Caspase-3, ß-actin, programmed cell death protein 4 (PDCD4) and relate-proteins of cell pathways. Tumor volume and weight were tested via animal experiments. Results: MAT could not affect the growth of SV-HUC-1 cell but MAT promoted tumor cell apoptosis but restrained viability, invasion and migration. Furthermore, LINC00472 was prominently low expressed in BC tissues. MAT positively regulated LINC00472 and transfection with si-00472 could partly reverse the efficacies of MAT. Moreover, MAT enhanced PDCD4 expression by up-regulating LINC00472. Besides, we discovered MAT elevated PTEN but restrained PI3K/AKT proteins. Finally, tumor volume and weight were declined by MAT in vivo via up-regulating LINC00472. Conclusion: MAT restrained cell growth and metastasis but promoted PDCD4 expression by up-regulating LINC00472 via restraining PTEN/PI3K/AKT pathway in BC.

4.
Sci Rep ; 10(1): 1794, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32020014

RESUMO

Long non-coding (lnc) RNAs represent a fascinating class of transcripts that remains highly controversial mainly due to ambiguity surrounding overall biological relevance of these RNAs. Multitude of reverse genetics studies showing functionality of lncRNAs are unfortunately based on assays that are either plagued by non-specific effects and/or cannot unambiguously assign observed phenotypes to the transcript per se. Here, we show application of the novel CRISPR/Cas13 RNA knockdown system that has superior specificity compared to other transcript-targeting knockdown methods like RNAi. We applied this method to a novel widespread subclass of nuclear lncRNAs - very long intergenic non-coding (vlinc) RNAs - in a high-throughput phenotypic assay based on survival challenge in response to anticancer drug treatments. We used multiple layers of controls including mismatch control for each targeting gRNA to ensure uncovering true phenotype-transcript relationships. We found evidence supporting importance for cellular survival for up to 60% of the tested protein-coding mRNAs and, importantly, 64% of vlincRNAs. Overall, this study demonstrates utility of CRISPR/Cas13 as a highly sensitive and specific tool for reverse genetics study of both protein-coding genes and lncRNAs. Furthermore, importantly, this approach provides evidence supporting biological significance of the latter transcripts in anticancer drug response.

5.
Chemosphere ; 249: 126077, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32045752

RESUMO

Aerobic composting and anaerobic digestion with hydrolysis pretreatment are two mainstream methods used to recycle and reclaim sewage sludge. However, during these sludge treatment processes, many odors are emitted that may cause severe emotional disturbance and health risks to those exposed. This study identified odor pollution (i.e. sensory influence, odor contribution, and human risks) from samples collected during sludge aerobic composting throughout different seasons as well as during anaerobic digestion with hydrolysis pretreatment. Odor intensity, odor active values, and permissible concentration-time weighted averages for ammonia and five volatile sulfur compounds were assessed. The results revealed serious odor pollution from all sampling sites during aerobic composting, especially in winter. Excessively strong odors were identified in the composting workshop, with total odor active values between 997 and 8980 which accounted for 78.45%-96.18% of the total sludge aerobic composting plant. Levels of ammonia and dimethyl disulfide in the ambient air were high enough to harm employees' health. During anaerobic digestion, excessively strong odors were identified in dehydration workshop 2, and the total odor active values of six odors reached 32,268, with ammonia and hydrogen sulfide levels significant enough to harm human health.

6.
Addiction ; 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31961014

RESUMO

BACKGROUND AND AIMS: More than 20 cities in China have enacted local smoke-free laws that prohibit smoking in public places. Only two of these cities have examined the health impact of the law. Enacted in 2013, Qingdao's smoke free-law was stricter than most other municipal smoke-free laws because it did not allow designated smoking rooms. This study aimed to estimate the impact of Qingdao's smoke-free legislation on acute myocardial infarction (AMI) and stroke. DESIGN, SETTING AND PARTICIPANTS: We used an interrupted time-series design adjusting for underlying secular trends, seasonal patterns and meteorological factors to estimate the impact of the smoke-free law on AMI and stroke events among permanent residents aged 35 years or older in Qingdao, China. The study period was from 1 January 2010 to 31 December 2015, with a post-ban follow-up of approximately 2.5 years. MEASUREMENT: Outcome measures were weekly numbers of hospitalizations and deaths due to AMI/stroke. FINDINGS: A total of 10 371 and 56 101 patients were hospitalized, with a principal discharge diagnosis of AMI and stroke, respectively; 32 196 AMI and 49 711 stroke deaths occurred during the study period. Following the smoke-free legislation, an incremental 20% [95% confidence interval (CI) = 14-26%] and 8% (95% CI = 3-13%) decrease per year was observed in AMI and stroke hospitalization rates, respectively. Neither the immediate nor gradual change in AMI nor stroke mortality rates associated with the law was statistically significant (P > 0.05). Post-hoc subgroup analyses indicated that statistically significant reductions in AMI hospitalizations were evident among both the 35-64 (18% per year, 95% CI = 12-27%) and 65-84 (20% per year, 95% CI = 12-27%) age groups. Statistically significant reductions in stroke hospitalization were only in the older subgroup (13% per year, 95% CI = 8-18%). CONCLUSIONS: The 2013 smoke-free legislation in Qingdao, China was associated with reduction in hospitalization from acute myocardial infarction and stroke among permanent residents aged 35 years or older. There was no statistically significant reduction in mortality from acute myocardial infarctions or stroke.

7.
Molecules ; 25(3)2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31979158

RESUMO

Volatile organic compounds (VOCs) in wood furniture are an important factor that affects indoor air quality. In this study, radiata pine (Pinus radiata D. Don) was treated with sodium bicarbonate and ozone aqueous solution to reduce the VOC contents without sacrificing mechanical properties. The VOCs of radiata pine were identified by gas chromatography-mass spectrometry (GC-MS), and the functional group changes of wood samples were characterized by Fourier-transform infrared spectroscopy (FTIR). The results showed that the main VOCs of radiata pine include alkenes, aldehydes, and esters. The sodium bicarbonate and ozone treatments almost eliminated the VOC contents of radiata pine. The two treatments mentioned above had little effect on compressive strength and surface color of radiata pine.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31943630

RESUMO

HCHO has been confirmed as an active intermediate in the methanol-to-hydrocarbon (MTH) reaction, and is critical for interpreting the mechanisms of coke formation. Here, HCHO was detected and quantified during the MTH process over HSAPO-34 and HZSM-5 by in situ synchrotron radiation photoionization mass spectrometry. Compared with conventional methods, excellent time-resolved profiles were obtained to study the formation and fate of HCHO, and other products during the induction, steady-state reaction, and deactivation periods. Similar formation trends of HCHO and methane, and their close correlation in yields suggest that they are derived from disproportionation of methanol at acidic sites. In the presence of Y2 O3 , the amount of HCHO changes, affecting the hydrogen-transfer processes of olefins into aromatics and aromatics into cokes. The yield of HCHO affects the aromatic-based cycle and the formation of ethylene, indicating that ethylene is mainly formed from the aromatic-based cycle.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31990168

RESUMO

Black phosphorus nanoparticles (BP NPs) possess great advantages in photocatalysis owing to the rich surface active sites, extremely high carrier mobility, and strong visible-near-infrared light response. However, the complex preparation process, poor stability, and rapid carrier recombination restrict their successful application in photocatalysis. Herein, the above problems are resolved by preparing BP NPs through a facile sonication-assisted hydrothermal method. To further improve the stability and photocatalytic activity, BP NPs are tightly anchored onto ZnS to prepare ZnS-BP porous nanosheets. With the Zn-P coordination bond built between them, higher stability, enhanced carrier transport ability, and excellent hydrogen adsorption and desorption equilibrium of photocatalysts are achieved. An efficient and recyclable photocatalytic hydrogen evolution rate of 1561 µmol h-1 g-1 is obtained under visible-light irradiation, which is superior to that of previously reported BP-based photocatalysts. Besides, the photocatalytic mechanism is investigated based on the theoretical calculations and experimental characterizations. The charge transfer dynamics are studied by surface photovoltage (SPV), ultrafast transient absorption (TA), X-ray absorption spectra (XAS), electrochemical impedance spectroscopy (EIS), and steady-state photoluminescence (PL) spectra. This work set a reference for the design of high-performance BP-related nanomaterials in solar energy storage and conversion.

10.
Int J Med Robot ; 16(2): e2081, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31955492

RESUMO

BACKGROUND: Due to its unique dexterity and safety, continuum manipulators have been widely used in small constrained environment. However, its flexibility also brings negative effects such as poor stiffness and low strength. This paper presents a novel variable-stiffness sheath for continuum manipulators applied in minimally invasive surgery. METHODS: We present a variable-stiffness sheath based on shape memory alloy (SMA) for each module of the continuum manipulators. The stiffness of the sheath can be continuously adjusted depending on the voltage between both ends of the sheath, along with the phase transformation of SMA between austenite and martensite. RESULTS: The experimental results demonstrate that the stiffness of the sheath and single module are able to increase up to 223.1% and 139.2%, separately, which verify the correctness of the proposed variable stiffness method. CONCLUSION: The robot integrated with the variable-stiffness sheath is demonstrated to possess a fine capacity of variable stiffness.

11.
J Hazard Mater ; 384: 121321, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31655386

RESUMO

The degradation of di-(2-ethylhexyl) phthalate (DEHP) was examined as an example to capitalize on the potential interactions of peroxydisulfate (PS) and ferrous iron (Fe2+) in the model Day-1/Day-90 and on-site hydraulic fracturing wastewater (FWW). The primary oxidative radicals in the Fe2+/PS system (i.e., SO4- and OH) were less effective for the degradation of DEHP (6.45%) in ultrapure water. Both chloride (Cl-) and bromide (Br-) at equivalent molar ratio with PS enhanced DEHP degradation (15.6% and 45.5%, respectively) via the generation of Cl and Br radicals, whereas the degradation rate was inhibited by the excessive amount of Cl- or Br- in the Day-1/Day-90 FWW. However, the co-presence of ethylene glycol (C2H4(OH)2, 0.043% v/v in the FWW) and halide ions (Cl- or Br-, 0.05 mM) resulted in the highest removal efficiency of 82.6 - 88.5% within 10 min by Fe2+/PS. Further investigation revealed that the formation of reductive alcohol radicals (C2H3(OH)2) slowed down or replenished the Fe2+ exhaustion. This study demonstrated that the Fe2+/PS-based advanced oxidation may show a synergistic interplay with Cl-/Br- and C2H4(OH)2 in the FWW, which depends on their relative concentrations. Thus, the inherent constituents in the fracturing wastewater can be utilized for the catalytic degradation of co-existing organic contaminants.

12.
Chin Med J (Engl) ; 133(2): 221-228, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31764175

RESUMO

OBJECTIVE: Alternative splicing can generate various structural and functional protein isoforms. Recently, accumulating evidence shows a relationship between alternative splicing and cancer. Cancer is a complex and chronic disease that involves malignant transformation. In this review, we consider alternative splicing events in relation to the hallmarks of cancer cells, and discuss current therapies to treat cancer-related to alternative splicing. DATA SOURCES: Data cited in this article are from the PubMed and Embase database, primarily focusing on research published from 2000 to 2018. STUDY SELECTION: Articles were selected with the search terms "alternative splicing," "cancer cell," "tumor microenvironment," and "therapy." RESULTS: Alternative splicing plays an important role in tumorigenesis, development, and escape from cell death. Taking this trait of cancer cells into consideration will allow more definite diagnoses of cancer, and allow the development of more effective medicines to intervene in cancer that could focus on controlling alternative splicing or competitively binding to the final products. CONCLUSIONS: Alternative splicing is common in cancer cells. Consideration of alternative splicing may allow different strategies for cancer therapy or the identification of novel biomarkers for cancer diagnosis.

13.
J Mech Behav Biomed Mater ; 101: 103418, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31514055

RESUMO

Recent demands in clinical applications drive a large amount of research to plasma sprayed hydroxyapatite (HA) composite coatings. Herein, graphene nanosheet (GNS) reinforced HA coating was fabricated using plasma spray, the effect of heat and hydrothermal treatments (hereafter referred to as thermal treatment) on microstructural evolution and mechanical properties of the composite coating were investigated. Thermally treated GNS/HA coating not only exhibited ~47.1% improvement in HA crystallinity and more denser microstructure, but also displayed increased surface roughness (3 times of that of the as-sprayed sample) due to the fact that GNSs facilitated HA nanoparticle precipitation on the coating surface. Fracture toughness of the as-sprayed HA coating increased by up to ~44.1% at 2.0 wt% GNSs owing to GNS pullout, GNS bridging and arresting of crack propagation by the embedded GNSs. As for thermally treated HA coatings, crack propagation arrested by the sintered regions was found to act as an important toughening mechanism, but thermal treatment introduced more structural defects into the GNSs and led to the reductions in their length and thickness, resulting in negligible enhancement in toughness of the GNS/HA coating.

14.
Anal Chem ; 92(1): 603-606, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31846300

RESUMO

Knowledge on the initial and intermediate pyrolysis products of biomass is essential for the mechanistic investigation of biomass pyrolysis and further optimization of upgrading processes. The conventional method can only detect the final products, which do not resemble the initial or intermediate pyrolysis products. Here, we introduce a direct orifice sampling combined with atmospheric pressure photoionization mass spectrometry (APPI-MS) for in situ online analysis of the evolved volatile initial products from the pyrolysis of biomass. Pyrolysis experiments of both dimeric model compound (guaiacylglycerol-ß-guaiacyl ether, GGGE) and poplar wood were carried out to validate the generality of the method. Generally, secondary reactions can be reduced by shortening the distance between the sample and sampling orifice. Large molecular-weight initial products up to trimers were detected during the pyrolysis of poplar wood, and no initial products larger than trimers were detected. It is inferred that in situ APPI immediately after sample extraction ensures efficient and effective product detection. Furthermore, the present work offers a promising feasible method for online tracing of reaction intermediates not only in pyrolysis but also in various reactive processes (e.g., catalytic reaction, oxidation) under operando conditions.

15.
Sci Rep ; 9(1): 17881, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784644

RESUMO

Groundwater pollution and human health risks caused by leachate leakage have become a worldwide environmental problem, and the harm and influence of bacteria in leachate have received increased attention. Setting the isolation distance between landfill sites and groundwater isolation targets is particularly important. Firstly, the intensity model of pollutant leakage source and solute transport model were established for the isolation of pathogenic Escherichia coli. Then, the migration, removal and reduction of bacteria in the aerated zone and ground were simulated. Finally, the isolation distance was calculated based on the acceptable water quality limits, and the influence of hydrogeological arameters was analyzed based on the parameter uncertainty. The results of this study suggest that the isolation distances vary widely ranging from 106 m-5.46 km in sand aquifers, 292 m-13.5 km in gravel aquifers and 2.4-58.7 km in coarse gravel aquifers. The gradient change of groundwater from 0.001 to 0.05 resulted in the isolation distance at the highest gradient position being 2-30 times greater than that at the lowest gradient position. There was a difference in the influence of the thickness of the vadose zone. For example, under the same conditions, with the increase of the thickness of the aeration zone, the isolation distance will be reduced by 1.5-5 times, or under the same thickness of the aeration zone, the isolation distance will be significantly shortened. Accordingly, this needs to be determined based on specific safety isolation requirements. In conclusion, this research has important guiding significance for the environmental safety assessment technology of municipal solid waste landfill.

16.
Chin J Cancer Res ; 31(5): 749-758, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31814679

RESUMO

Objective: To evaluate the efficacy and safety profile of first-line bevacizumab (Bev)-containing pemetrexed-platinum chemotherapy in a real-world Chinese cohort with advanced non-squamous non-small cell lung cancer (NS-NSCLC). Methods: A total of 415 eligible patients with NS-NSCLC who received first-line pemetrexed-platinum chemotherapy at National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College between February 2010 and September 2017 were reviewed retrospectively: 309 Bev(-) and 106 Bev(+) cases. Bev was administered at 7.5 mg/kg every 3 weeks in the Bev(+) group. To reduce the risk of a selection bias, a propensity score-matching (PSM) was conducted and 105 pairs of Bev(-) and Bev(+) cases were identified. Results: The median duration of follow-up was 15.8 months. The median progression-free survival (PFS) was prolonged significantly in the Bev(+) group than in the Bev(-) group in overall (9.8vs. 7.8 months, P=0.006) and PSM pairs (9.8 vs. 6.6 months, P<0.001). Moreover, patients receiving maintenance therapy with pemetrexed plus Bev had longer PFS than those interrupted after induction chemotherapy, or those receiving mono-maintenance with pemetrexed (12.3vs. 4.8 vs. 8.6 months; P<0.001). Multivariate analyses revealed Bev to be one of the favorable prognostic factors for PFS, along with the predictor of maintenance therapy. Conclusions: First-line induction and maintenance therapy with Bev (7.5 mg/kg every 3 weeks) combined with pemetrexed-platinum chemotherapy was efficacious and superior to non-Bev chemotherapy in Chinese patients with advanced NS-NSCLC.

17.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(6): 872-877, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31880120

RESUMO

OBJECTIVE: To study the relationship between the copy numbers of repetitive units at variable number tandem repeat (VNTR) loci of Mycobacterium tuberculosis complex (MTBC) with its diversity of protein profiles. METHODS: The MTBC strains were subjected to genotyping using multiple locus variable number tandem repeat analysis (MLVA). Also, the principal component analysis (PCA) was performed for bacterial protein profiles of MTBC using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The relationship between the polymorphism of VNTR loci and PCA clustering was analyzed. RESULTS: A total of 157 MTBC strains were collected. 146 MTBC strains (MS identification score values ≥1.700) were performed PCA and three clusters, clusterⅠ(61 strains), clusterⅡ(26 strains) and cluster Ⅲ(59 strains), were generated. Polymorphic diversities were observed in 24 VNTR loci, among them, 7 were highly various, 7 were moderately, and 10 were low various. The polymorphism of Mtub39, QUB26 and QUB4156 loci were correlated with the results of MALDI-TOF MS clustering (P=0.000, P=0.035, P=0.017). CONCLUSION: The polymorphism of Mtub39, QUB26 and QUB4156 loci in MTBC was correlated with the difference of MALDI-TOF MS protein profiles, suggesting that these loci may play a role in regulating the composition of protein profiles of MTBC strains.


Assuntos
Repetições Minissatélites , Mycobacterium tuberculosis , Genótipo , Polimorfismo Genético , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
18.
Nat Prod Res ; : 1-7, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31741411

RESUMO

Seven lignans and eight phenylpropanoids, including one new lignan, 7S,8R,8'R-5,5'-dimethoxyariciresinol-4-O-ß-D-glucopyranoside (1), were isolated from the liquid juice of Phyllostachys edulis. Their structures were established by extensive spectroscopic analyses. The absolute configuration of the new compound was determined by comparing its experimental electronic circular dichroism (ECD) spectra with calculated ECD spectra. All compounds were evaluated for their anti-inflammatory activity and xanthine oxidase inhibitor activity, and the results showed that compound 9 exhibited a moderate activity in these two bioassays. In addition, all the compounds can be detected in health panda faeces by LC-MS.

19.
Water Res ; 166: 115026, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514100

RESUMO

In this study, the performance of LaCoO3 (LCO) catalytic ozonation was evaluated comprehensively, including the degradation efficiency of benzotriazole (BZA) as a typical emerging pollutant, toxic bromate reduction and the disinfection by-products (DBPs) precursors removal ability in effluent organic matter (EfOM), as well as EfOM reactive activity in catalytic ozonation. Additionally, the reduction of toxic halogenated by-products in (catalytic) ozonation was reported, which was not focused on previous researches before. Results showed that LCO catalytic ozonation improved the removal efficiency of BZA, UV254 and SUVA via enhanced HO· formation. Interestingly, LCO catalytic ozonation showed the ability on the reduction of aldehydes and toxic halogenated organic by-products. Moreover, the formed [trichloromethane (TCM)], [bromochloroacetonitrile (BCAN)] and [dichloroacetamide (DCAcAm)] decreased significantly in catalytic ozonation. Catalytic ozonation was also able to remove DBPs precursors to decline the formation of DBPs, such as TCM, bromodichloromethane (BDCM), trichloroacetonitrile (TCAN) and trichloronitromethane (TCNM). This process was involved in the transformation of EfOM in catalytic ozonation, which was confirmed by multi-spectrum methods, two-dimensional correlation spectroscopy (2D-COS) and hetero-spectral 2D-COS. In summary, LCO was shown to be an effective catalyst to improve the performance of the sole ozonation on the removal of emerging contaminants and DBPs precursors, as well as toxic by-products reduction. Additionally, the strategy of toxic by-products reduction in catalytic ozonation was proposed. Results indicated this technology was an important contribution on removal of refractory organics and formation of toxic by-products in water supply and wastewater treatment industry.


Assuntos
Poluentes Ambientais , Ozônio , Poluentes Químicos da Água , Purificação da Água , Águas Residuárias
20.
mBio ; 10(4)2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31363026

RESUMO

Endogenous retroviruses (ERVs) are transposable elements that cause host genome instability and usually play deleterious roles in disease such as tumorigenesis. Recent advances also suggest that this "enemy within" may encode a viral mimic to induce antiviral immune responses through viral sensors. Here, through whole-genome transcriptome analysis with RNA sequencing (RNA-Seq), we discovered that a full-length ERV-derived long noncoding RNA (lncRNA), designated lnc-EPAV (ERV-derived lncRNA positively regulates antiviral responses), was a positive regulator of NF-κB signaling. lnc-EPAV expression was rapidly upregulated by viral RNA mimics or RNA viruses to facilitate the expression of RELA, an NF-κB subunit that plays a crucial role in antiviral responses. Transcriptome analysis of lnc-EPAV-silenced macrophages showed that lnc-EPAV was critical for RELA target gene expression and innate immune responses. Consistently, lnc-EPAV-deficient mice exhibited reduced expression of type I interferons (IFNs) and, consequently, increased viral loads and mortality following lethal RNA virus infection. Mechanistically, lnc-EPAV promoted expression of RELA by competitively binding to and displacing SFPQ, a transcriptional repressor of Rela Altogether, our work demonstrates an alternative mechanism by which ERVs regulate antiviral immune responses.IMPORTANCE Endogenous retroviruses are transposable genetic elements comprising 8% to 10% of the human and mouse genomes. Although most ERVs have been inactivated due to deleterious mutations, some are still transcribed. However, the biological functions of transcribed ERVs are largely unknown. Here, we identified a full-length ERV-derived lncRNA, designated lnc-EPAV, as a positive regulator of host innate immune responses. We found that silencing lnc-EPAV impaired virus-induced cytokine production, resulting in increased viral replication in cells. The lnc-EPAV-deficient mice exhibited enhanced susceptibility to viral challenge. We also found that lnc-EPAV regulated expression of RELA, an NF-κB subunit that plays a critical role in antiviral responses. ERV-derived lncRNA coordinated with a transcription repressor, SFPQ, to control Rela transcription. Our report provides new insights into the previously unrecognized immune gene regulatory mechanism of ERV-derived lncRNAs.

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