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1.
Environ Sci Technol ; 2020 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-32062968

RESUMO

Recently, perfluoroalkyl substances (PFASs) have received great attention from both academia and industry due to their persistence and health risks. Here, we developed a simple ternary self-assembled micelle composite, consisting of photosensitive substance-indole acetic acid, cationic surfactant-cetyltrimethylammonium bromide and contaminant (PFAS). Owing to the rapid hydrated electron transfer from IAA to PFAS in the micelle, PFAS degradation and defluorination were greatly enhanced even under ambient conditions. After 2.5 h UV-irradiation, the perfluorooctanoic acid concentration decreased from 10 mg L-1 to ~60 ng L-1, which is below the drinking water health advisory level of US EPA. Meanwhile, the dissolved organic carbon content of the reaction solution was also reduced to ~3 mg L-1, due to the quick settlement and automatical separation of the micelle. Furthermore, the newly developed composite was also adaptable to a wide pH range (pH 4~8), attributing to the barrier created by the ternary micelle system. This novel self-assembly method is expected to directly treat industrial PFAS-containing wastewater or PFAS-enriched concentrates derived from adsorption processes. The conceptually new advanced reduction technique represents a major breakthrough towards PFASs rapid destruction and efficient usage of hydrated electrons, and might also shed light on other environmental applications.

2.
Virus Genes ; 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32065329

RESUMO

In this study, we investigated the molecular characteristics and spatio-temporal dynamics of GII.P17-GII.17 norovirus in Zhoushan Islands during 2013-2018. We collected 1849 samples from sporadic acute gastroenteritis patients between January 2013 and August 2018 in Zhoushan Islands, China. Among the 1849 samples, 134 (7.24%) samples were positive for human norovirus (HuNoV). The complete sequence of GII.17 VP1 gene was amplified from 31 HuNoV-positive samples and sequenced. A phylogenetic tree was constructed based on the full-length sequence of the VP1 gene. Phylogenetic analysis revealed that the GII.17 genotype detected during 2014-2018 belongs to the new GII.17 Kawasaki variant. Divergence analysis revealed that the time of the most recent common ancestor (TMRCA) of GII.17 in Zhoushan Islands was estimated to be between 1997 and 1998. The evolutionary rate of the VP1 gene of the GII.17 genotype norovirus was 1.14 × 10-3 (95% HPD: 0.62-1.73 × 10-3) nucleotide substitutions/site/year. The spatio-temporal diffusion analysis of the GII.17 genotype identified Hong Kong as the epicenter for GII.17 dissemination. The VP1 gene sequence of Zhoushan Island isolates correlated with that of Hong Kong and Japan isolates.

3.
Medicine (Baltimore) ; 99(8): e19157, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32080093

RESUMO

INTRODUCTION: Peritoneal metastasis (PM) is a frequent condition in patients presenting with gastric cancer, especially in younger patients with advanced tumor stages. Computer tomography (CT) is the most common noninvasive modality for preoperative staging in gastric cancer. However, the challenges of limited CT soft tissue contrast result in poor CT depiction of small peritoneal tumors. The sensitivity for detecting PM remains low. About 16% of PM are undetected. Deep learning belongs to the category of artificial intelligence and has demonstrated amazing results in medical image analyses. So far, there has been no deep learning study based on CT images for the diagnosis of PM in gastric cancer. WE PROPOSED A HYPOTHESIS: CT images in the primary tumor region of gastric cancer had valuable information that could predict occult PM of gastric cancer, which could be extracted effectively through deep learning. OBJECTIVE: To develop a deep learning model for accurate preoperative diagnosis of PM in gastric cancer. METHOD: All patients with gastric cancer were retrospectively enrolled. All patients were initially diagnosed as PM negative by CT and later confirmed as positive through surgery or laparoscopy. The dataset was randomly split into training cohort (70% of all patients) and testing cohort (30% of all patients). To develop deep convolutional neural network (DCNN) models with high generalizability, 5-fold cross-validation and model ensemble were utilized. The area under the receiver operating characteristic curve, sensitivity and specificity were used to evaluate DCNN models on the testing cohort. DISCUSSION: This study will help us know whether deep learning can improve the performance of CT in diagnosing PM in gastric cancer.

4.
Water Res ; 174: 115604, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32088388

RESUMO

Microorganism-derived dissolved organic nitrogen (mDON) represents a significant and inevitable portion of dissolved organic nitrogen (DON) in the wastewater biotreatment processes. In the existing method, mDON concentrations are indirectly measured by the values of DON concentrations from the reactors with DON-free influent. However, this becomes problematic when influent contains DON. Especially when the real wastewater is involved, the paucity of the direct methods to quantitatively measure mDON is a major barrier to further research. This limitation is due to the difficulty of segregating mDON from the other nitrogenous organics, e.g., influent DON. In this study, we propose the ASM-mDON model based on ASM #1, which incorporates the production and consumption of mDON in the activated sludge processes to predict the mDON concentrations. In four independent lab-scale tests, our model was established and calibrated to obtain the accurate values of mDON (R2 = 0.929, p < 0.05), and the validity and applicability of the model were successfully examined by comparing the simulated and measured data. Moreover, the universality of the ASM-mDON model was further confirmed by simulating mDON production in a full-scale wastewater treatment plant. A reasonable prediction of mDON formation was shown in a full-scale test (1.98 ± 0.71 mg/L in June and 1.51 ± 0.54 mg/L in July) and is indirectly supported by an algal bioassay (p < 0.05, t-test). This study provides a useful approach to the efficient and accurate evaluation of mDON formation, which will improve current strategies designed to minimize the effluent mDON in wastewater bioprocesses.

5.
Eur J Radiol ; 124: 108858, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32035370

RESUMO

PURPOSE: To verify the feasibility of synthetic MRI in quantitative evaluation of lumbar intervertebral disk (IVD) degeneration, as compared to the conventional CarrPurcell-Meiboom-Gill (CPMG) T2 mapping approach. METHODS: Twenty-four patients with chronic low back pain participated in this study. Patients underwent routine lumbar MRI, CPMG T2 mapping, and synthetic MRI (MAGiC) acquisition. The degree of IVD degeneration was derived from T2-weighted images according to the Pfirrmann classification. The correlation between two T2 measurements was assessed by Pearson correlation and Bland-Altman analysis. Statistical differences of quantitative values obtained from MAGiC data across different degeneration grades were quantified by one-way ANOVA. ROC curves were used to test the sensitivity and specificity of CPMG and MAGiC T2 measurements for assessing Pfirrmann grading. RESULTS: T2 values obtained from CPMG and MAGiC data exhibited strong positive correlation (r = 0.962, p < 0.01). Significant negative correlations were found between quantitative values (p < 0.05) and the Pfirrmann grading. Quantitative values show significant difference across Pfirrmann grading groups (one-way ANOVA, p < 0.001). Additionally, post-hoc tests show significant differences of T1 and T2 between adjacent groups among grades I-IV (p < 0.05), while the significant differences of PD were only observed between adjacent groups among grades II-IV (p < 0.05). There is no significant difference between AUCs of T2 values obtained from CPMG and MAGiC data in differentiating grade I/ II, grade II/ III and grade III/IV. CONCLUSIONS: The synthetic MRI may be used to provide quantitative biomarkers for assessing the level of lumbar intervertebral disc degeneration.

6.
Curr Biol ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32059767

RESUMO

The regulatory mechanisms by which neurons coordinate their physiology and connectivity are not well understood. The Drosophila olfactory receptor neurons (ORNs) provide an excellent system to investigate this question. Each ORN type expresses a unique olfactory receptor, or a combination thereof, and sends their axons to a stereotyped glomerulus. Using single-cell RNA sequencing, we identified 33 transcriptomic clusters for ORNs and mapped 20 to their glomerular types, demonstrating that transcriptomic clusters correspond well with anatomically and physiologically defined ORN types. Each ORN type expresses hundreds of transcription factors. Transcriptome-instructed genetic analyses revealed that (1) one broadly expressed transcription factor (Acj6) only regulates olfactory receptor expression in one ORN type and only wiring specificity in another type, (2) one type-restricted transcription factor (Forkhead) only regulates receptor expression, and (3) another type-restricted transcription factor (Unplugged) regulates both events. Thus, ORNs utilize diverse strategies and complex regulatory networks to coordinate their physiology and connectivity.

8.
Biochem Biophys Res Commun ; 523(4): 859-866, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-31954517

RESUMO

MicroRNA-25-3p (miR-25-3p) has been reported to be closely related with oxidative stress and apoptosis. Here, we aimed to detect the effects of miR-25-3p in the primarily cultured hippocampal neurons. Kainic acid (KA) was used to induce epileptic seizures in the rats. We predicted that oxidative stress responsive 1 (OXSR1) might be a potential target of miR-25-3p with TargetScan prediction and luciferase assays, and the primarily cultured hippocampal neurons were exposed to Mg2+-free solution for 3 h to induce spontaneous recurrent epileptiform discharges (SREDs). Then, the expression of miR-25-3p and OXSR1 in the rats hippocampi and primarily cultured hippocampal neurons were detected. Those SREDs neurons were treated with miR-25-3p mimic, miR-25-3p inhibitor or/and OXSR1 over-expression vector, and SREDs, oxidative stress and apoptosis were observed. We found down-regulation of miRNA-25-3p and up-regulation of OXSR1 in hippocampi of KA-treated rats and Mg2+-free-treated neurons. MiRNA-25-3p mimic could down-regulate OXSR1 expression, inhibit SREDs, reduce oxidative stress and decrease apoptosis. Additionally, over-expression of OXSR1 weakened those effects of miR-25-3p mimic. Those data indicated that miR-25-3p had anti-epileptic, anti-oxidant and anti-apoptosis effects on the primarily cultured neurons through targeting OXSR1, which provided a novel target for the treatment of epilepsy.

9.
J Med Chem ; 63(3): 1397-1414, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-31934767

RESUMO

Colony-stimulating factor 1 receptor (CSF-1R) is involved in inflammatory disorders as well as in many types of cancer. Based on high-throughput screening and docking results, we performed a detailed structure-activity-relationship study, leading to the discovery of a new series of compounds with nanomolar IC50 values against CSF-1R without the inhibition of fibroblast growth factor receptors. One of the most promising hits, compound 29, potently inhibited CSF-1R kinase with an IC50 value of 0.7 nM, while it showed no inhibition to the same family member FMS-like tyrosine kinase 3. Compound 29 displayed excellent anti-inflammatory effects against RAW264.7 macrophages indicated by significant inhibition against the activation of the CSF-1R pathway with low cytotoxicity. In addition, compound 29 exhibited strong in vivo anti-inflammatory efficacy alongside favorable drug characteristics. This novel compound 29 may serve as a new drug candidate with promising applications in inflammatory disorders.

10.
Acta Diabetol ; 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31938886

RESUMO

AIMS: To investigate the correlation of impairment in skeletal muscle and heart in spontaneous type 2 diabetes mellitus (T2DM) rhesus monkeys using magnetic resonance image (MRI). METHODS: Fifteen T2DM monkeys and fourteen healthy control (HC) monkeys were included. The microcirculation of skeletal muscle [skeletal muscle blood flow (SMBF), skeletal muscle oxygen extraction fraction (SMOEF)] and the function and strain of heart were evaluated by MRI. Three regions of interests were chosen on the soleus muscle (SOL), gastrocnemius muscle (GAS) and tibialis anterior muscle (TA) for image analysis. RESULTS: Eight T2DM monkeys and eight HC monkeys were obtained the full data. The SMBF reserves and SMOEF reserves were found significantly decreased in T2DM during inflation in SOL, GAS and TA muscles (all p < 0.05), and the SMBF reserves decreased during hyperemia in GAS and TA muscles (all p < 0.05). In these monkeys, the global peak longitudinal strain (longitudinal PS), peak systolic longitudinal strain rate (longitudinal PSSR) and peak diastolic longitudinal strain rate (longitudinal PDSR) were seen significantly different in T2DM compared to HC monkeys (all p < 0.05). The longitudinal PSSR was found negatively correlated with SMBF reserves in SOL, GAS and TA during inflation in all monkeys. CONCLUSIONS: The impaired microcirculation of skeletal muscle and the myocardial deformation were found in T2DM monkeys with normal ejection fraction. And a negative correlation was existed in the longitudinal PSSR and the SMBF reserves.

11.
Acta Crystallogr C Struct Chem ; 76(Pt 1): 23-29, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31919304

RESUMO

The Co-MOF poly[[diaqua{µ4-1,1,2,2-tetrakis[4-(1H-1,2,4-triazol-1-yl)phenyl]ethylene-κ4N:N':N'':N'''}cobalt(II)] benzene-1,4-dicarboxylic acid benzene-1,4-dicarboxylate], {[Co(C34H24N12)(H2O)2](C8H4O4)·C8H6O4}n or {[Co(ttpe)(H2O)2](bdc)·(1,4-H2bdc)}n, (I), was synthesized by the hydrothermal method using 1,1,2,2-tetrakis[4-(1H-1,2,4-triazol-1-yl)phenyl]ethylene (ttpe), benzene-1,4-dicarboxylic acid (1,4-H2bdc) and Co(NO3)2·6H2O, and characterized by single-crystal X-ray diffraction, IR spectroscopy, powder X-ray diffraction (PXRD), luminescence, optical band gap and valence band X-ray photoelectron spectroscopy (VB XPS). Co-MOF (I) shows a (4,4)-connected binodal two-dimensional topology with a point symbol of {44·62}{44·62}. The two-dimensional networks capture free neutral 1,4-H2bdc molecules and bdc2- anions, and construct a three-dimensional supramolecular architecture via hydrogen-bond interactions. MOF (I) is a good photocatalyst for the degradation of methylene blue and rhodamine B under visible-light irradiation and can be reused at least five times.

13.
Cell ; 180(2): 373-386.e15, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31955847

RESUMO

Molecular interactions at the cellular interface mediate organized assembly of single cells into tissues and, thus, govern the development and physiology of multicellular organisms. Here, we developed a cell-type-specific, spatiotemporally resolved approach to profile cell-surface proteomes in intact tissues. Quantitative profiling of cell-surface proteomes of Drosophila olfactory projection neurons (PNs) in pupae and adults revealed global downregulation of wiring molecules and upregulation of synaptic molecules in the transition from developing to mature PNs. A proteome-instructed in vivo screen identified 20 cell-surface molecules regulating neural circuit assembly, many of which belong to evolutionarily conserved protein families not previously linked to neural development. Genetic analysis further revealed that the lipoprotein receptor LRP1 cell-autonomously controls PN dendrite targeting, contributing to the formation of a precise olfactory map. These findings highlight the power of temporally resolved in situ cell-surface proteomic profiling in discovering regulators of brain wiring.

14.
Sci Total Environ ; 710: 136375, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31923693

RESUMO

Direct membrane filtration has shown great potential in wastewater treatment and resource recovery in terms of its superior treated water quality, efficient nutrient recovery, and sustainable operation, especially under some scenarios where biological treatment is not feasible. This paper aims to give a comprehensive review of the state-of-the-art of direct membrane filtration processes (including pressure-driven, osmotic-driven, thermal-driven, and electrical-driven) in treating different types of wastewater for water reclamation and resource recovery. The factors influencing membrane performance and treatment efficiency in these direct membrane filtration processes are well illustrated, in which membrane fouling was identified as the main challenge. The strategies for improving direct membrane filtration performance, such as physical and chemical cleaning techniques and pretreatment of feed water, are highlighted. Towards scaling-up and long-term operation of direct membrane filtration for effective wastewater reclamation and resource recovery, the challenges are emphasized and the prospects are discussed.

15.
Int Immunopharmacol ; 80: 106187, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31931372

RESUMO

IL-17A-producing CD4+ T helper cells (Th17) are crucial for the development of inflammatory and autoimmune diseases and thus are exploited for clinical immunotherapies. Emerging evidence suggests Th17 cells are heterogeneous and able to adopt both pathogenic and non-pathogenic phenotypes which are shaped by environmental and genetic factors. On one hand, IL-6 in concert with TGFß1 can induce non-pathogenic Th17 cells (non-pTh17), which are not effective in inducing tissue inflammation. On the other hand, IL-6, IL-1ß with IL-23 induce pathogenic Th17 cells (pTh17) to induce immune pathologies in various tissues. Th17 cells could be both pathogenic and non-pathogenic in a content-dependent manner in vivo. Understanding how the generation and pathogenicity of pTh17 cells are regulated will aid us to devise more effective immunotherapy. In this review, we summarize recent advances in the differentiation and regulation of Th17 cells especially pTh17 cells in vitro and in vivo. The emerging results revealing the specific molecular control of pTh17 cells are highlighted.

16.
J Inorg Biochem ; 205: 110987, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31927402

RESUMO

The dyshomeostasis of copper, iron and zinc ions in pathological conditions, which are critically involved in many brain activities, may result in an accumulation of them in the brain that has been reported for the patients with Alzheimer's disease. Conformational change is one of the consequences of metal-peptide interaction as we observed for the interaction of the Cu2+ with microtubule binding repeats of tau protein, which ultimately cause peptide aggregation. Herein, we show that interaction of Zn2+, Fe2+, and Fe3+ with full-length tau peptide R1 (tau244-274) and R4 (tau337-368), the first and fourth microtubule binding repeats of tau protein, lead to the conformational changes. And while the Electrospray ionization-mass spectrometry (ESI-MS) confirmed the complexation of Zn2+ and Fe2+ with both R1 and R4, there is no evidence for metalation of R1 or R4 with Fe3+.

17.
Environ Int ; 135: 105326, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31794939

RESUMO

Initial attachment plays an important role in biofilm formation in wastewater treatment processes. However, the initial attachment process mediated by N-acyl-homoserine lactones (AHLs) is difficult to be fully understood due to the lack of non-invasive and on-line investigation techniques. In this study, the AHL-regulated wastewater biofilm attachment was quantified using ultrasonic time-domain reflectometry (UTDR) as an in-situ and non-invasive monitoring technique. Results demonstrated that the reversible adhesion time in municipal and industrial wastewaters was significantly decreased in the presence of exogenous AHLs. Biofilm thickness in municipal and industrial wastewaters increased significantly with the addition of exogenous AHLs. Also, the addition of acylase delayed the initial biofilm formation (lengthened reversible adhesion time and decreased biofilm thickness and density). Compared with biofilm behavior in the presence of low concentrations of AHLs (4.92 ± 0.17 µg/L), both reversible adhesion time and biofilm thickness were not significantly increased (p > 0.05) with an increase in AHL concentration (9.75 ± 0.41 µg/L). Furthermore, the addition of exogenous AHLs resulted in significant changes in the attached bacterial community structures, in which both QS and quorum-quenching (QQ) bacteria were stimulated. The current work presents an effective approach to in-situ monitoring of the regulation of AHL-mediated QS in the initial attachment of biofilms, especially in the reversible adhesion process, which may provide a potential strategy to facilitate biofilm establishment in wastewater treatment processes.

18.
Sci Total Environ ; 711: 134437, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31812393

RESUMO

The response mechanism of wastewater treatment biofilms to salt stress has not yet been fully established. The aim of this study was to reveal the comprehensive biological effects of salinity on biofilm microbial community and metabonomic characteristics. The study assessed performance at a range of sodium chloride (NaCl) concentrations of 0.6, 14 and 20 g/L. Biofilm coverage rate decreased significantly with increasing NaCl concentrations. High NaCl concentrations resulted in more compact and smoother biofilm morphologies. NaCl concentrations affected bacterial community variation at the class and genus level, with Gammaproteobacteria being the most dominant Proteobacteria, exhibiting NaCl tolerance at concentrations ranging from 0 to 20 g/L. Also, NaCl sensitive or tolerant species were identified, such as Pseudomonas and Planococcus, respectively. Dominant metabolites in wastewater treatment biofilms belonging to nucleotide, lipid, vitamin, amino acid and carbohydrate metabolism pathways decreased with increasing NaCl concentrations. High concentrations of NaCl regulated cell motility, transcription and membrane transport functions. In particular, the activity of ABC transporters were up-regulated at NaCl concentrations of 0.6 g/L and down-regulated at higher salinity concentrations. In addition, transcription machinery were inhibited under the stress of 14 g/L NaCl. These findings further our understanding of the short-term adaption mechanisms of wastewater treatment biofilms to high NaCl concentration environments.

19.
Water Res ; 170: 115352, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31812816

RESUMO

The impacts of salt accumulation, through adjusting the solid retention time (SRT), in the bioreactor on the bioprocess as well as membrane performance of a high retention nanofiltration membrane bioreactor (NF-MBR) and subsequent reverse osmosis (RO) process for water reclamation are addressed in this study. The build-up of salts (i.e., Ca, Mg, PO4) is a function of SRT, hydraulic retention time (HRT) and membrane rejection. Despite the accumulation of salts, both NF-MBRs at SRT of 30 and 60 days, achieved (i) similar biodegradation efficiency; (ii) excellent organic removal (> 97%); and (iii) excellent ammonia removal (> 98%). Extending the SRT could improve the microbial bio-flocculation capability, but did not influence the microbial activity, viability, and community structure. However, more severe membrane fouling was observed in the NF-MBR with elevated salt levels, which was attributed to the greater formation of calcium phosphate scale and Ca-polysaccharides complex (i.e., irreversible fouling layer) as well as the cake-enhanced-osmotic-pressure (CEOP) effect. Although both NF-MBRs produced comparable quality of permeate, a higher RO membrane fouling rate was observed when the permeate of NF-MBR with SRT at 60 days was fed to the RO system, implying organic compositions in NF-MBR permeate may influence RO performance.


Assuntos
Purificação da Água , Água , Reatores Biológicos , Membranas Artificiais , Osmose
20.
ACS Appl Mater Interfaces ; 12(1): 1495-1503, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31814386

RESUMO

Light-emitting diode based electronic screens emit near-ultraviolet radiation, which causes harm to the human eye after prolonged exposure. Thus, it is of paramount importance to prepare a sensitive and adjustable visible near-ultraviolet sensor for retinal warning. Herein, a series of bipyridine derivatives were synthesized to investigate effects of substituent groups and anions on photochromic properties via both experimental and theoretical studies. The introduction of dual hydrogen bonding urea onto substituted groups significantly accelerated the photochromic rate due to strong intermolecular interactions, which reduces molecular spacing and promotes the electron-transfer effect. Moreover, the photochromic rate was tuned by changing the size of the anion. Larger anions widen the molecular spacing and weaken the electron transfer and eventually lead to a decrease in the photochromic rate. Finally, bipyridine derivatives were printed on a polyethylene terephthalate film or paper as a sensitive, adjustable, and visible sensor to monitor near-ultraviolet radiation emitted by an light-emitting diode screen.

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