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1.
Inorg Chem ; 2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33586424

RESUMO

Protonolysis of ß-diketiminato (nacnac) rare-earth metal bis-alkyl complexes LnacnacLnR2(THF) (Ln = Y and Lu) with 2 equiv of Ph2PNHPh or Ph2PCH2NHPh afforded the bis-amido complexes LnacnacY(Ph2PNPh)2 and LnacnacLn(Ph2PCH2NPh)2 (Ln = Y and Lu). Metalation of the latter complexes with 1 equiv of Ni(COD)2 led to the isolation of unusual heterobimetallic Ni(II)-Ln(III) complexes formed via P-C bond cleavage of one [Ph2PCH2NPh]- ligand. Notably, both the imine PhN═CH2 and phosphide Ph2P- fragments from the P-C bond cleavage were trapped in the Ni(II)-Ln(III) core with a relatively weak interaction between the two metal centers. The Ni(II)-Y(III) complex have exhibited versatile reactivity, such as coordination of isonitrile to the Ni(II) center, insertion of nitrile with the coordinated imine, and ring-opening of the epoxide by nucleophilic attack from the phosphide group.

2.
Br J Ophthalmol ; 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397654

RESUMO

AIM: To compare the efficacy of macular buckling (MB) and pars plana vitrectomy (PPV) for full-thickness macular holes (FTMH) and associated macular detachment (MD) in highly myopic eyes. METHODS: Prospective interventional case series of eyes undergoing PPV or MB for FTMH and MD. MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA) at postoperative month 24. Other measured outcomes include the initial surgical success rate, macular hole closure rate and the progression of myopic maculopathy. RESULTS: A total of 53 eyes from 53 participants were included in this study (26 participants receiving MB and 27 participants receiving PPV), and finally 49 eyes from 49 participants (25 participants in the MB group and 24 participants in the PPV group) were analysed. At postoperative month 24, the BCVA had improved significantly in those that underwent either MB (p<0.001) or PPV (p=0.04). The difference between the groups was not significant (p=0.653). The surgical failure rate after the primary treatment was significantly higher in the PPV group than the MB group (25.00% vs 4.00%, respectively; p=0.04). The macular closure rate was higher in the MB group compared with the PPV group, but the difference was not statistically significant (64.00% vs 58.33%, respectively; p=0.45). Myopic maculopathy development may be more severe following PPV than following MB surgery. CONCLUSION: Patients with high myopia obtained anatomical and functional improvements from either MB or PPV. However, MB achieved a significantly higher success rate in retinal reattachment compared with PPV. TRIAL REGISTRATION NUMBER: NCT03433547.

3.
Sci Total Environ ; 766: 144230, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33418257

RESUMO

Nitrite-dependent anaerobic methane-oxidation (n-damo) is a potential novel technology for nitrogen removal in anaerobic wastewater treatment. In this study, Geobacter sulfurreducens (G) was applied to stimulate n-damo activity. Conductive materials such as nano-magnetite (M) or aggregating agents such as hydroxylapatite (H) were co-added with G. sulfurreducens to further investigate the enhancement effect. Results showed that the nitrite reduction activity of the n-damo culture was promoted by G. sulfurreducens, with 1.71-2.38 times higher in treatment G, G + M, and G + H than that in the control, but was inhibited by the single addition of hydroxylapatite. N-damo bacterial abundances based on the qPCR of the n-damo-specific pmoA gene increased in treatments with G. sulfurreducens, compared with that of the control. High-throughput sequencing analysis revealed the enrichment of uncultured phylum WPS-2 in treatments with G. sulfurreducens. Fluorescence in situ hybridization verified the co-occurrence pattern of n-damo bacteria (NC10), G. sulfurreducens, and type-I aerobic methanotrophs (Methylomonas spp.). The above results corroborated the microbial interspecies electron transfer (MIET) potentiality of the n-damo enrichment. Our study provides a novel pathway for enhancing MIET to stimulate n-damo process.


Assuntos
Metano , Nitritos , Anaerobiose , Desnitrificação , Geobacter , Hibridização in Situ Fluorescente , Oxirredução
4.
Environ Sci Technol ; 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33492142

RESUMO

Traditional harsh chemical cleaning-in-place (CIP) is corrosive to membranes but has limited inhibition on refouling, a tough problem for long-term operation of reverse osmosis (RO). Mild enzymatic cleaning (at pH 9) is a promising alternative but lacks long-term verification and insightful elucidation. In this study, we investigated the instantaneous efficiency, postcleaning refouling, and biological effect of enzymatic CIP (compounded with lipase, protease, and sodium dodecyl sulfate) on practical RO membranes during a 500 h multicycle operation. The enzymatic CIP had an average cleaning efficiency of 77%, which is comparable to a commercial harsh CIP benchmark (pH > 12). It mitigated refouling by shaping the biofilm into a loose and porous architecture where newly arrived organics conformed standard blocking, whereas harsh chemicals rendered a smooth and dense gel layer with quick refouling in intermediate blocking or cake filtration mode. Such structural disparities were dominated by polysaccharides according to quantitative chemical analyses. Gene sequencing and ecological network analysis further proved that the behavior of polysaccharide-related keystone species (such as Sphingomonas and Xanthomonas) significantly changed after long-term enzymatic treatment. In this regard, the mild selective pressure of enzymatic reagents can directionally regulate microbial dynamics, alter foulant layer structure via bio-organic synchronicity, mitigate refouling, and eventually improve the sustainability of RO operation.

5.
BMC Infect Dis ; 21(1): 14, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407216

RESUMO

BACKGROUND: The levels of serum D-dimer (D-D) in children with Mycoplasma pneumoniae pneumonia (MPP) were assessed to explore the clinical significance of D-D levels in refractory MPP (RMPP). METHOD: A total of 430 patients with MPP were enrolled between January 2015 and December 2015 and divided into a general MPP (GMPP) group (n = 306) and a RMPP group (n = 124). Clinical data, D-D level, white blood cell (WBC) count, proportion of neutrophils (N%), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), alanine transaminase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) were compared between the two groups. Multivariate logistic regression was performed to identify independent predictors of RMPP. RESULTS: (1) Hospitalization time, preadmission fever duration, total fever duration, WBC, N %, CRP, LDH, ESR, ALT, AST, and D-D were significantly higher in the RMPP group than those in the GMPP group (all P < 0.05). (2) Correlation analysis showed that D-D was positively correlated with WBC, CRP, ESR, and LDH, and could be used to jointly evaluate the severity of the disease. (3) Multivariate logistic regression analysis identified preadmission fever duration, CRP, LDH and DD as independent risk factors for RMPP (all P < 0. 05). D-D had the highest predictive power for RMPP (P < 0.01). The D-D level also had a good ability to predict pleural effusion and liver injury (all P < 0.01). CONCLUSION: Serum D-D levels were significantly increased in patients with RMPP, indicating that excessive inflammatory response and vascular endothelial injury with prolonged duration existed in this patient population. Increased levels of serum D-D may be used as an early predictor of RMPP and the occurrence of complications. Our findings provide a theoretical basis for the early diagnosis of RMPP, early intervention and excessive inflammatory response in the pathogenesis of mycoplasma.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Mycoplasma pneumoniae/genética , Pneumonia por Mycoplasma/sangue , Pneumonia por Mycoplasma/diagnóstico , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Sedimentação Sanguínea , Proteína C-Reativa/análise , Criança , Pré-Escolar , Feminino , Humanos , L-Lactato Desidrogenase/sangue , Contagem de Leucócitos , Modelos Logísticos , Masculino , Mycoplasma pneumoniae/isolamento & purificação , Neutrófilos/patologia , Derrame Pleural/etiologia , Pneumonia por Mycoplasma/complicações , Pneumonia por Mycoplasma/microbiologia , Estudos Retrospectivos , Fatores de Risco
6.
Aging (Albany NY) ; 13(3): 4063-4078, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33493137

RESUMO

Pluripotent stem cells (PSCs) have a unique energetic and biosynthetic metabolism compared with typically differentiated cells. However, the metabolism profiling of PSCs and its underlying mechanism are still unclear. Here, we report PSCs metabolism profiling and identify the purine synthesis enzymes, phosphoribosyl pyrophosphate synthetase 1/2 (PRPS1/2), are critical for PSCs stemness and survival. Ultra-high performance liquid chromatography/mass spectroscopy (UHPLC-MS) analysis revealed that purine synthesis intermediate metabolite levels in PSCs are higher than that in somatic cells. Ectopic expression of PRPS1/2 did not improve purine biosynthesis, drug resistance, or stemness in PSCs. However, knockout of PRPS1 caused PSCs DNA damage and apoptosis. Depletion of PRPS2 attenuated PSCs stemness and assisted PSCs differentiation. Our finding demonstrates that PRPS1/2-mediated purine biosynthesis is critical for pluripotent stem cell stemness and survival.

7.
J Low Genit Tract Dis ; 25(1): 22-26, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33347045

RESUMO

OBJECTIVE: The aim of the study was to evaluate the Cobas 4800 Assay and the SeqHPV Assay with self (S) and direct (D) cervical samples in the Chinese Multicenter Screening Trial (CHIMUST). MATERIALS AND METHODS: The CHIMUST is a large population-based multicenter clinical trial, and 10,885 women aged 30-59 years from 15 sites in 7 provinces with no cervical cancer screening for 3 years were eligible. All participating women contributed one self-collected sample (S) and 1 physician-collected endocervical sample (DL). The self-collected sample was first applied to the solid media transport card (SS), and then, the brush placed in 6 mL of ThinPrepSolution (SL). All samples were tested with Cobas 4800 and SeqHPV high-risk HPV assays. Patients human papillomavirus positive (self or direct) were recalled for colposcopy and biopsies. RESULTS: A total of 10,399 women had complete data. The mean age was 43.9 years. A total of 1.4% (142/10,399) had cervical intraepithelial neoplasia (CIN) 2+ and 0.5% (54/10,339) had CIN 3+. In the liquid specimens, the overall HPV infection rates were 10.8% for Cobas and 10.9% for SeqHPV in D sample, and 13.7% for Cobas and 11.6% for SeqHPV in SL sample, respectively. The sensitivity of Cobas-DL, Cobas-SL, SeqHPV-DL, and SeqHPV-SL for CIN 2+ was 95.07%, 95.07%, 94.33%, and 96.48%, respectively. The specificity of Cobas-DL, Cobas-SL, SeqHPV-DL, and SeqHPV-SL for CIN 2+ was 90.38%, 87.35%, 90.21%, and 89.53%, respectively. There were no differences in sensitivity when applying the 2 assays to both self- and directly collected samples in liquid transport media (p > .05). CONCLUSIONS: Both Cobas and SeqHPV screening assays using both self-collected and directly endocervical collected specimens demonstrate similar sensitivity for the detection of CIN 2+ and CIN 3+.

8.
Work ; 68(s1): S281-S287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33337428

RESUMO

BACKGROUND: Many occupations require workers to stand for prolonged periods, which can cause discomfort, pain and even injures. Some supermarkets in life provide a foot pad for checkout staff to let them stand on it at work, thereby reducing standing fatigue caused by standing for a long time. The inclined platform is the same as the foot pad mentioned above. That is, the staff stepped on it and relieved standing fatigue to a certain extent. OBJECTIVE: The study aims to analyze how the standing angle affects fatigue among prolonged standing workers and tries to find an inclined platform with a specific angle to reduce standing fatigue. METHODS: This experiment studied fatigue of the inclined platforms with different angles on prolonged standing workers, eight participants were selected to participate in the test. The plantar pressures and sEMG (Surface Electromyography) were used to collect the physiological information change of prolonged standing participants in the lower limb and waist. The visual analogue scale was used as a subjective method to measure the psychological fatigue. RESULTS AND CONCLUSION: The study highlights the relationship between standing angle and lower limb fatigue. The inclination of the standing platform has different effects on the participants under different time conditions. When participants stand on inclined platforms at 0°, 5° and 10°, the iEMG (Integrated Electromyography) values of the gastrointestinal muscle were not significantly different until the third sampling point (40 minutes). After that self-regulation of lower limb muscles is better when standing on an inclined platform between 5° and 10°, it has a certain effect on alleviating lower limb fatigue. This knowledge is crucial for the design of the inclined working platforms fitting the needs of prolonged standing workers.

9.
Sci Total Environ ; : 143546, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33257079

RESUMO

Solar-driven interfacial evaporation aiming at producing clean water without conventional energy consumption, has attracted worldwide research interest. Nevertheless, complex preparation processes and costly absorber materials might be the challenges for the practical application of this technology. Herein, a ceramic fiber was preferably selected as the supporting matrix, and a composite of activated carbon and carbon black was used as the photothermal material. Different evaporation system configurations containing the as-synthesized solar absorber were constructed and compared. It was found that, due to an improved heat insulation and water transportation, the one-dimensional configuration exhibited a maximum evaporation rate of 1.70 kg m-2 h-1 and the highest solar-to-vapor energy conversion efficiency of 91.8% under one sun. Furthermore, material cost and preparation complexity were also incorporated to assess the comprehensive performance of this solar absorber. The ceramic fiber-based activated carbon­carbon black composite (CF-ACB) solar absorber proposed in this contribution, featuring cost-effectiveness, easiness-to-manufacture and great evaporation performance, illuminated its application potential of future solar desalination to provide clean water for people who live in remote and less developed areas with limited and insufficient access to fresh water.

10.
Med Hypotheses ; 144: 110221, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33254528

RESUMO

Carcinogenesis was postulated as the result of the local buildup of strong acids such as hydrogenchloride which may trigger metastasis. A previous study revealed that bicarbonate raised tumor pH and suppressed metastases. The phosphate groups in DNA on neutrophil extracellular traps possess hydrogen bonding capacity and can accept protons. The proteins commonly found in neutrophil extracellular traps such as CCDC25, myeloperoxidase (MPO), histone H3, peptidylarginine deiminase 4 (PAD4) possess basic amino acid content at about 20.2%, 12.8%, 24.3% and 13.0% respectively, which attracts anions such as chloride. The striking 20.2% basic amino acid content in CCDC25 is similar to that of typical oncoproteins. Local hydrogenchloride may be the dominant impetus for metastasis, accounting for the anticancer effects of virtually all weak organic acids, acetic acid and lactic acid in particular.

11.
Environ Res ; 193: 110565, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33275920

RESUMO

Nitrite-dependent anaerobic methane-oxidizing (n-damo) process has a promising prospect in anaerobic wastewater treatment, utilizing methane as the sole electron source to remove nitrite. However, the metabolic activity of n-damo bacteria is too low for practical application. This study aimed to stimulate n-damo process by introducing conductive nano-magnetite and/or electron shuttle anthraquinone-2,6-disulfonate (AQDS), and also set a comparative treatment of adding insulated ferrihydrite. The results showed that the nitrite reduction rate was enhanced the most significantly in treatment with nano-magnetite, approximately 1.6 times higher than that of the control without any supplement. While ferrihydrite application showed an adverse effect on n-damo process. The well-known aerobic methane oxidizer Methylomonas spp. was found to be enriched under n-damo condition with the supplementation of nano-magnetite and/or AQDS, but abundance of n-damo bacteria did not exhibit significant increase. It was hypothesized that Methylomonas spp. could be survived under anaerobic n-damo condition using oxygen produced by n-damo bacteria for the self-growth, and the nitrite reduction could be promoted through the enhancement of microbial interspecies electron transfer triggered by the introduction of conductive materials. It opens a new direction for the stimulation of n-damo activity, which needs more evidences to verify the hypothetic mechanism.

12.
Infect Agent Cancer ; 15(1): 72, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33292341

RESUMO

BACKGROUND: The solid transport media is a small size card that allows fast, easy DNA extraction from a variety of biological samples. In 2016 we developed a solid media transport card; for that pilot study to control the self-collection we used a pseudo-self-collection technique. The current study expands this prior work using true self-collections and only the POI card, and aims to evaluate the solid media transport card to detect HR-HPV in self-samples compared to liquid transport media. METHODS: Ten thousand eight hundred eighty-five women between the ages of 30-59 with no screening for 3 years were enrolled. The self-collected sample was first applied to a new solid media transport card (Labeled as SC) then the brush placed in 6 ml ThinPrep liquid (Labeled as SL). Then a physician collected a direct endocervical specimen into ThinPrep liquid (Labeled as DL). Samples were tested with Cobas 4800 and the SeqHPV NGS assay for HR-HPV. Patients positive on any test were recalled for colposcopy and biopsy. RESULTS: Ten thousand three hundred thirty-nine participants had complete data. The mean age was 43.9 years. CIN 2+ rates were 1.4% (142/10339). The agreement in HPV detection between the two different self-sample collection media was also good (Cobas HPV kappa = 0.86; SeqHPV kappa = 0.98). Tested with Cobas, the sensitivity of Cobas-SL and Cobas-SC for CIN 2+ was95.07 and 94.37%; and for CIN3+ was 96.30, 96.30% respectively. The specificity of Cobas-SC, and Cobas-SL for CIN2+ was 88.74 and 87.35%; for CIN3 was 88.04and 86.65% respectively. Tested with SeqHPV, the sensitivity for CIN2+ of Seq-SC and Seq-SL was 95.77 and 96.48%; for CIN3+, both the SC and SL specimens had a sensitivity of 100%. The specificity for CIN2+ of Seq-SC and Seq-SL was 89.54 and 89.53%; for CIN3+ was 88.84,88.82% respectively. For both HR-HPV assays, the sensitivities were similar for the two self-sample media (SC vs SL, p = 1.00). CONCLUSIONS: The solid transport card for collecting vaginal self-samples as accurate as liquid transport media assayed by two different PCR based HR-HPV tests. The solid transport media is a suitable medium for collecting and storing vaginal self-samples.

13.
J Immunol Res ; 2020: 6644687, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33294466

RESUMO

The remodeling of the extracellular matrix (ECM) in the parenchyma plays an important role in the development of acute respiratory distress syndrome (ARDS), a disease characterized by lung injury. Although it is clear that TGF-ß1 can modulate the expression of the extracellular matrix (ECM) through intracellular signaling molecules such as Smad3, its role as a therapeutic target against ARDS remains unknown. In this study, a rat model was established to mimic ARDS via intratracheal instillation of lipopolysaccharide (LPS). A selective inhibitor of Smad3 (SIS3) was intraperitoneally injected into the disease model, while phosphate-buffered saline (PBS) was used in the control group. Animal tissues were then evaluated using histological analysis, immunohistochemistry, RT-qPCR, ELISA, and western blotting. LPS was found to stimulate the expression of RAGE, TGF-ß1, MMP2, and MMP9 in the rat model. Moreover, treatment with SIS3 was observed to reverse the expression of these molecules. In addition, pretreatment with SIS3 was shown to partially inhibit the phosphorylation of Smad3 and alleviate symptoms including lung injury and pulmonary edema. These findings indicate that SIS3, or the blocking of TGF-ß/Smad3 pathways, could influence remodeling of the ECM and this may serve as a therapeutic strategy against ARDS.

14.
Plants (Basel) ; 9(12)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33261119

RESUMO

Mikania cordata, the only native congener of the invasive weed Mikania micrantha in China, is an ideal species for comparative study to reveal the invasion mechanism. However, its genome resources are lagging far behind its congener, which limits the comparative genomic analysis. Our goal is to characterize the genome of M. cordata by next-generation sequencing and propose a scheme for long-read genome sequencing. Previous studies have shown that the genomic resources of the host plant would be affected by the endophytic microbial DNA. An aseptic sample of M. cordata will ensure the proper genome in downstream analysis. Because endophytes are ubiquitous in the greenhouse-grown M. cordata, the in vitro culture with cefotaxime or timentin treatment was undertaken to obtain the aseptic plantlets. The in vivo mother plant and in vitro plantlets were used to survey the genome. The microbial contamination in M. cordata was recognized by blast search and eliminated from the raw reads. The decontaminated sequencing reads were used to predict the genome size, heterozygosity, and repetitive rate. The in vivo plant was so contaminated that microbes occupied substantial sequencing resources and misled the scaffold assembly. Compared with cefotaxime, treatment with timentin performed better in cultivating robust in vitro plantlets. The survey result from the in vitro plantlets was more accurate due to low levels of contamination. The genome size was estimated to be 1.80 Gb with 0.50% heterozygosity and 78.35% repetitive rate. Additionally, 289,831 SSRs were identified in the genome. The genome is heavily contaminated and repetitive; therefore, the in vitro culture technique and long-read sequencing technology are recommended to generate a high-quality and highly contiguous genome.

15.
Inorg Chem ; 59(23): 17276-17281, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33231077

RESUMO

A biocompatible Y(III)-based metal-organic framework [Y4(TATB)2]·(DMF)3.5·(H2O) (ZJU-16, H3TATB= 4,4',4''-(1,3,5-triazine-2,4,6-triyl) tribenzoic acid) was synthesized, and it was adopted to load Mn2+ for chemodynamic therapy. Meanwhile, ibuprofen sodium (IBUNa), an anti-inflammatory drug, was introduced to increase the amount of Mn2+ (about 5.66 wt %) due to the low loading capacity of Mn2+. Mn&IBUNa@ZJU-16 which was loaded by Mn2+ and IBUNa exhibited significant effects of chemodynamic therapy and excellent inhibition of the 4T1 tumor cell growth, implying its long-term prospects in chemodynamic therapy and its possibility in bimodal cancer therapy.

16.
Bioresour Technol ; 320(Pt B): 124371, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33186803

RESUMO

An electrically stimulated anaerobic-aerobic coupled system was developed to improve the biodegradation of refractory phenolics. Expected 4-nitrophenol, 2, 4-dinitrophenol, and COD removals in the system with aerobic cathodic and anaerobic anodic chambers were approximately 53.7%, 45.4%, 22.3% (intermittent mode) and 37.9%, 19.8%, 17.3% (continuous mode) higher than that in the control system (26.0 ± 6.4%, 30.7 ± 7.1%, 49.8 ± 3.0%). 2, 4-dichlorophenol removal in the system with aerobic anodic and anaerobic cathodic chambers was approximately 28.5% higher than that in the control system (71.4 ± 5.7%). The contribution of the aerobic cathodic/anodic chambers to the removal of phenolic compounds was higher than that of the anaerobic cathodic/anodic chambers. The species related to phenolic biodegradation (Rhodococcus, Achromobacter, PSB-M-3, and Sphingobium) were enriched in the cathodic and anodic chambers of the system. These results showed that intermittent electrical stimulation could be a potential alternative for the efficient degradation of refractory phenolics.

17.
Toxicology ; 447: 152627, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33161053

RESUMO

PM2.5 exposure elevates the level of reactive oxygen species (ROS) in the lungs and leads to lung injury or other pulmonary conditions. Nrf2 is a key antioxidative regulator that suppresses ROS production. Extracellular vesicles (EVs) secreted by adipose mesenchymal stem cells (ADSCs) have been identified as therapeutic as well as potential drug/gene/protein carriers. In this study, we established rat (PM2.5, 100 µL, 5 mg/mL) or cell (PM2.5, 50 µg/mL) models to conduct in vivo and in vitro studies on the adverse pulmonary effects of PM2.5. Our findings indicated that the initial responses to PM2.5 exposure were robust oxidative stress and inflammation. EVs and antioxidative EVs (Antioxi-EVs, derived from ADSCs that overexpress Nrf2) had been tested as interventions in PM2.5-treated rat or cell models through tracheal instillation or co-incubation. Treatment with EVs or Antioxi-EVs (3 × 1010 particles in vivo and 1 × 109in vitro) was found to have a suppressive effect on the levels of ROS and inflammatory cytokines, with Antioxi-EVs having a superior effect on anti-oxidative stress. In particular, the occurrence of lung injury or cell apoptosis correlated positively with the ROS level, and inhibition of ROS by upregulating Nrf2 alleviated lung injury and cell apoptosis. Furthermore, treatment with EVs or Antioxi-EVs increased the level of M2-like macrophages as compared to treatment with PBS and further reduced IL-6 and TNF-α levels. Our results suggest that Antioxi-EVs can reduce the severity of oxidative stress, inflammation, and lung injury induced by PM2.5via anti-oxidative stress and immunomodulation pathways.

18.
Water Res ; 189: 116552, 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33166921

RESUMO

A novel granular activated carbon-synergized anaerobic membrane bioreactor (GAC-AnMBR), consisted of four expanded bed anaerobic bioreactors with GAC carriers and a membrane tank, was established in pilot scale (10 m3/d) to treat real municipal wastewater (MWW) at ambient temperature seasonally fluctuating from 35 to 5 °C. It showed sound organic removal over 86% with the permeate COD less than 50 mg/L even at extremely low temperatures below 10 °C. COD mass balance analysis revealed that membrane rejection (with a contribution rate of 10%-20%) guaranteed the stable organic removal, particularly at psychrophilic temperature. The methane yield was over 0.24 L CH4 (STP)/g COD removed at mesophilic temperature and 0.21 L CH4 (STP)/g COD removed at 5-15 °C. Pyrosequencing of microbial communities suggested that lower temperature reduced the abundance of the methane producing bacteria, but the methane production was enhanced by selectively enriched Methanosaeta, syntrophic Syntrophobacter and Smithella and exoelectrogenic Geobacter for direct interspecies electron transfer (DIET) on the additive GAC. Compared with previously reported pilot-scale AnMBRs, the GAC-AnMBR in this study showed better overall performance and higher stability in a wide temperature range of 5-35 °C. The synergistic effect of GAC on AnMBR guaranteed the robustness of GAC-AnMBR against temperature, which highlighted the applicational potential of GAC-AnMBR, especially in cold and temperate climate regions.

19.
Environ Sci Technol ; 54(23): 15414-15423, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33180465

RESUMO

Nitrite oxidation is the primary pathway that generates nitrate in engineered systems. However, little is known about the role of a novel nitrite-oxidizing bacteria (NOB) genus Candidatus Nitrotoga in activated sludge systems. To elucidate key factors that impact NOB community composition, laboratory-scale sequencing batch reactors (SBRs) were designed and operated under the same conditions as real wastewater treatment plants to achieve considerable nitrogen removal and similar community; then, different conditions including temperature (T), dissolved oxygen (DO), free nitrous acid (FNA), and free ammonia (FA) were applied. The 16S rRNA gene-based PCR and sequence analysis illustrated that Ca. Nitrotoga were abundant even at ambient temperature, thus further challenging the previous conception of them being solely cold-adapted. Ca. Nitrotoga are less competitive than Nitrospira during oxygen deficiency, indicating its lower affinity to dissolved oxygen. Ca. Nitrotoga are the dominant nitrite oxidizers under regular exposure to FNA and FA due to their relatively higher resistance than other NOB toward these two effective biocides. Therefore, this study demonstrates that Ca. Nitrotoga can play an important role in biological nitrogen removal and also highlights the need for multiple strategies for NOB suppression for the next-generation, shortcut nitrogen removal.

20.
Soft Matter ; 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33146639

RESUMO

Conventional conductive hydrogels usually lack self-healing properties, but might be favorable for smart electronic applications. Therefore, we present the fabrication of conductive self-healing hydrogels that merge the merits of electrical conductivity and self-healing properties. The conductive self-healing hydrogel composite was prepared by using single-walled carbon nanotubes (SWCNTs), poly(vinyl alcohol) (PVA), and a poly(N,N-dimethyl acrylamide) copolymer derivative modified with pyrene and borate functional moieties. While the tethered pyrene groups of the copolymer facilitated an even dispersion of the conductive components, i.e., SWCNTs, in aqueous solution via π-π stacking, the hydrogel system was formed via covalent dynamic cross-linking through tetrahedral borate ion interaction with the -OH group of PVA. The hydrogel composites exhibited bulk conductivity (1.27 S m-1 with 8 mg mL-1 SWCNTs) with a fast and autonomous self-healing ability that restored 95% of the original conductivity within 10 s under ambient conditions. Accordingly, due to their outstanding properties, we postulate that these composites may have potential in biomedical applications, such as tissue engineering, wound healing or electronic skins.

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