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1.
Biomed Pharmacother ; 129: 110356, 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32535388

RESUMO

Paclitaxel-induced neuropathic pain (PINP) is a dose-limiting side effect and is refractory to widely used analgesic drugs. Previous studies have demonstrated a protective role of peroxisome proliferator-activated receptor gama (PPARγ) in neuropathic pain. However, whether PPARγ activation could alleviate PINP remains to be elucidated. Our previous study has validated the analgesic effect of oltipraz, an nuclear factor erythroid-2 related factor 2 (Nrf2) activator, in a rat model of PINP. In this study, we tested the hypothesis that rosiglitazone, a selective agonist of PPARγ, could attenuate PINP through induction of Nrf2/heme oxygenase-1 (HO-1) signaling pathway. Paclitaxel was injected intraperitoneally on four alternate days to induce neuropathic pain. Paw withdrawal threshold was used to evaluate mechanical allodynia. Western blot and immunofluorescence were used to examine the expression and distribution of PPARγ, Nrf2 and HO-1 in the spinal cord. Our results showed that rosiglitazone attenuated established PINP and delayed the onset of PINP via activation of PPARγ, which were reversed by PPARγ antagonist GW9662. Moreover, rosiglitazone inhibited downregulation of PPARγ in the spinal cord of PINP rats. Furthermore, the analgesic effect of rosiglitazone against PINP was abolished by trigonelline, an Nrf2 inhibitor. Finally, rosiglitazone significantly increased expression of Nrf2 and HO-1 in the spinal cord of PINP rats. Collectively, these results indicated that PPARγ activation might mitigate PINP through activating spinal Nrf2/HO-1 signaling pathway. Our results may provide an alternative option for PINP patients.

2.
PLoS Pathog ; 16(6): e1008633, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32511266

RESUMO

DNA viruses can hijack and manipulate the host chromatin state to facilitate their infection. Multiple lines of evidences reveal that DNA virus infection results in the host chromatin relocation, yet there is little known about the effects of viral infection on the architecture of host chromatin. Here, a combination of epigenomic, transcriptomic and biochemical assays were conducted to investigate the temporal dynamics of chromatin accessibility in response to Bombyx mori nucleopolyhedrovirus (BmNPV) infection. The high-quality ATAC-seq data indicated that progressive chromatin remodeling took place following BmNPV infection. Viral infection resulted in a more open chromatin architecture, along with the marginalization of host genome and nucleosome disassembly. Moreover, our results revealed that chromatin accessibility in uninfected cells was regulated by euchromatic modifications, whereas the viral-induced highly accessible chromatin regions were originally associated with facultative heterochromatic modification. Overall, our findings illustrate for the first time the organization and accessibility of host chromatin in BmNPV-infected cells, which lay the foundation for future studies on epigenomic regulation mediated by DNA viruses.

4.
Microbiome ; 8(1): 89, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32517753

RESUMO

BACKGROUND: Recent studies have significantly expanded our knowledge of viral diversity and functions in the environment. Exploring the ecological relationships between viruses, hosts, and the environment is a crucial first step towards a deeper understanding of the complex and dynamic interplays among them. RESULTS: Here, we obtained extensive 16S rRNA gene amplicon, metagenomics sequencing, and geochemical datasets from different depths of two highly stratified sulfidic mine tailings cores with steep geochemical gradients especially pH, and explored how variations in viral community composition and functions were coupled to the co-existing prokaryotic assemblages and the varying environmental conditions. Our data showed that many viruses in the mine tailings represented novel genera, based on gene-sharing networks. Siphoviridae, Podoviridae, and Myoviridae dominated the classified viruses in the surface tailings and deeper layers. Both viral richness and normalized coverage increased with depth in the tailings cores and were significantly correlated with geochemical properties, for example, pH. Viral richness was also coupled to prokaryotic richness (Pearson's r = 0.65, P = 0.032). The enrichment of prophages in the surface mine tailings suggested a preference of lysogenic viral lifestyle in more acidic conditions. Community-wide comparative analyses clearly showed that viruses in the surface tailings encoded genes mostly with unknown functions while viruses in the deeper layers contained genes mainly annotated as conventional functions related to metabolism and structure. Notably, significantly abundant assimilatory sulfate reduction genes were identified from the deeper tailings layers and they were widespread in viruses predicted to infect diverse bacterial phyla. CONCLUSIONS: Overall, our results revealed a depth-related distribution of viral populations in the extreme and heterogeneous tailings system. The viruses may interact with diverse hosts and dynamic environmental conditions and likely play a role in the functioning of microbial community and modulate sulfur cycles in situ. Video Abstract.

5.
Sci Total Environ ; 739: 140000, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32540668

RESUMO

Wuhan was the first city to adopt the lockdown measures to prevent COVID-19 spreading, which improved the air quality accordingly. This study investigated the variations in chemical compositions, source contributions, and regional transport of fine particles (PM2.5) during January 23-February 22 of 2020, compared with the same period in 2019. The average mass concentration of PM2.5 decreased from 72.9 µg m-3 (2019) to 45.9 µg m-3 (2020), by 27.0 µg m-3. It was predominantly contributed by the emission reduction (92.0%), retrieved from a random forest tree approach. The main chemical species of PM2.5 all decreased with the reductions ranging from 0.85 µg m-3 (chloride) to 9.86 µg m-3 (nitrate) (p < 0.01). Positive matrix factorization model indicated that the mass contributions of seven PM2.5 sources all decreased. However, their contribution percentages varied from -11.0% (industrial processes) to 8.70% (secondary inorganic aerosol). Source contributions of PM2.5 transported from potential geographical regions showed reductions with mean values ranging from 0.22 to 4.36 µg m-3. However, increased contributions of firework burning, secondary inorganic aerosol, road dust, and vehicle emissions from transboundary transport were observed. This study highlighted the complex and nonlinear response of chemical compositions and sources of PM2.5 to air pollution control measures, suggesting the importance of regional-joint control.

6.
Nano Lett ; 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32510963

RESUMO

Cell-membrane-camouflaged nanoparticles (CMC-NPs) have been increasingly exploited to develop various therapeutic tools due to their high biocompatibility and cell-type-specific tumor-targeting properties. However, the molecular mechanism of CMC-NPs for homotypic targeting remains elusive. Here, we develop a plasmonic imaging method by coating gold nanoparticles (AuNPs) with cancer cell membranes and perform plasmonic imaging of the interactions between CMC-NPs and living cells at the single-cell level. Quantitative analysis of CMC-NPs in a different clustering status reveals that the presence of cell membranes on CMC-NPs results in a 7-fold increase in homotypic cell delivery and nearly 2 orders of magnitude acceleration of the intracellular agglomeration process. Significantly, we identify that integrin αvß3, a cell surface receptor abundantly expressed in tumor cells, is critical for the selective cell recognition of CMC-NPs. We thus establish a single-cell plasmonic imaging platform for probing NP-cell interactions, which sheds new light on the therapeutic applications of CMC-NPs.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32537878

RESUMO

Protein 4 ' - phosphopantetheinylation is an essential post-translational modification (PTM) in prokaryotes and eukaryotes. So far, only five protein substrates of this specific PTM have been discovered in mammalian cells. These proteins are known to perform important functions including fatty acid biosynthesis and folate metabolism, as well as ß -alanine activation. In order to explore existing and new substrates of 4 ' - phosphopantetheinylation in mammalian proteomes, we designed and synthesized a series of new pantetheine analogue probes enabling effective metabolic labelling of 4 ' - phosphopantetheinylated proteins in HepG2 cells . In combination with a quantitative chemical proteomic platform, we enriched and identified all the currently known 4 ' - phosphopantetheinylated proteins with high confidence, and unambiguously determined their exact sites of modification. More encouragingly, we discovered, via targeted proteomics , a potential 4 ' - phosphopantetheinylated site in the protein of mitochondrial dehydrogenase/reductase SDR family member 2 (DHRS2).

8.
Gastroenterology ; 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32442562

RESUMO

BACKGROUD & AIMS: Although SARS-CoV-2 infects gastrointestinal tissues, little is known about the roles of gut commensal microbes in susceptibility to and severity of infection. We investigated changes in fecal microbiomes of patients with SARS-CoV-2 infection during hospitalization and associations with severity and fecal shedding of virus. METHODS: We performed shotgun metagenomic sequencing analyses of fecal samples from 15 patients with COVID-19 in Hong Kong, from February 5 through March 17, 2020. Fecal samples were collected 2 or 3 times per week from time of hospitalization until discharge; disease was categorized as mild (no radiographic evidence of pneumonia), moderate (pneumonia was present), severe (respiratory rate ≥30/min, or oxygen saturation ≤93% when breathing ambient air), or critical (respiratory failure requiring mechanical ventilation, shock, or organ failure requiring intensive care). We compared microbiome data with those from 6 subjects with community-acquired pneumonia and 15 healthy individuals (controls). We assessed gut microbiome profiles in association with disease severity and changes in fecal shedding of SARS-CoV-2. RESULTS: Patients with COVID-19 had significant alterations in fecal microbiomes compared with controls, characterized by enrichment of opportunistic pathogens and depletion of beneficial commensals, at time of hospitalization and at all timepoints during hospitalization. Depleted symbionts and gut dysbiosis persisted even after clearance of SARS-CoV-2 (determined from throat swabs) and resolution of respiratory symptoms. The baseline abundance of Coprobacillus, Clostridium ramosum, and Clostridium hathewayi correlated with COVID-19 severity; there was an inverse correlation between abundance of Faecalibacterium prausnitzii (an anti-inflammatory bacterium) and disease severity. Over the course of hospitalization, Bacteroides dorei, Bacteroides thetaiotaomicron, Bacteroides massiliensis, and Bacteroides ovatus, which downregulate expression of ACE2 in murine gut, correlated inversely with SARS-CoV-2 load in fecal samples from patients. CONCLUSIONS: In a pilot study of 15 patients with COVID-19, we found persistent alterations in the fecal microbiome during the time of hospitalization, compared with controls. Fecal microbiota alterations were associated with fecal levels of SARS-CoV-2 and COVID-19 severity. Strategies to alter the intestinal microbiota might reduce disease severity.

9.
J Clin Pharm Ther ; 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32419173

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Vancomycin removal by dialysis uses methods that differ in type of dialysis membrane, dialysis fluxes and duration, ultrafiltration rate and Kt/Vurea (K = dialyser urea clearance, t = time on dialysis and V = total body water) in case of nephrotoxicity. We applied continuous venous-venous haemodiafiltration (CVVHDF) to treat a paediatric case of vancomycin nephrotoxicity caused by high serum trough concentrations. CASE SUMMARY: We report the case of a 4-year and 7-month-old boy with serum trough concentration of vancomycin of 86.0 mg/L after a 2-day treatment with vancomycin. His serum creatinine increased from 13.3 µmol/L at baseline to 227.0 µmol/L. We discontinued vancomycin and performed a 22-hours CVVHDF with high-flux membrane. Vancomycin decreased by 69.4% (82.1-25.1 mg/L), and renal function improved. WHAT IS NEW AND CONCLUSION: Therapeutic drug monitoring and laboratory indicator measurements should be performed early during vancomycin treatment in paediatric patients with nephrotoxicity risk factors. Vancomycin removal by CVVHDF can be effective in paediatric acute kidney injury (AKI) associated with vancomycin-associated nephrotoxicity (VAN).

10.
J Vis Exp ; (159)2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-32421007

RESUMO

During the extrusion-based three-dimensional bioprinting process, liquid-like bioinks with low viscosity can protect cells from membrane damage induced by shear stress and improve the survival of the encapsulated cells. However, rapid gravity-driven cell sedimentation in the reservoir could lead to an inhomogeneous cell distribution in bioprinted structures and therefore hinder the application of liquid-like bioinks. Here, we developed a novel multilayered modified strategy for liquid-like bioinks (e.g., gelatin methacryloyl with low viscosity) to prevent the sedimentation of encapsulated cells. Multiple liquid interfaces were manipulated in the multilayered bioink to provide interfacial retention. Consequently, the cell sedimentation action going across adjacent layers in the multilayered system was retarded in the bioink reservoir. It was found that the interfacial retention was much higher than the sedimental pull of cells, demonstrating a critical role of the interfacial retention in preventing cell sedimentation and promoting a more homogeneous dispersion of cells in the multilayered bioink.

11.
Environ Microbiol ; 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32452607

RESUMO

Iron is virtually an essential nutrient for all organisms, to understand how iron contributes to virulence of plant pathogenic fungi, we identified ClFTR1 and ClNPS6 in maize pathogen Curvulaira lunata (Cochliobolus luntus) in this study. Disruption of ClNPS6 significant impaired siderophore biosynthesis. ClFTR1 and ClNPS6 did mediate oxidative stress, but had no significant impact on vegetative growth, conidiation, cell wall integrity (CWI) and sexual reproduction. Conidial germination delayed and appressoria formation reduced in ΔClftr1 comparing with wild type (WT) CX-3. Genes responsible for conidial germination, appressoria formation, non-host selective toxin biosynthesis and cell wall degrading enzymes were also down-regulated in transcriptome of ΔClftr1 and ΔClnps6 compared with WT. The conidial development, toxin biosynthesis, and polygalacturonase (PG) activity were impaired in the mutant strains with ClFTR1 and ClNPS6 deletion during their infection to maize. ClFTR1 and ClNPS6 were up-regulated expression at 12-24 hpi and 48-120 hpi in WT, respectively. ClFTR1 positively regulated conidial germination, appressoria formation in the biotrophy-specific phase. ClNPS6 positively regulates non-host selective toxin biosynthesis, and cell wall degrading enzyme activity in the necrotrophy-specific phase. Our results indicated that ClFTR1 and ClNPS6 were key genes of pathogen known to conidia development and virulence factors. This article is protected by copyright. All rights reserved.

12.
Mol Genet Genomic Med ; : e1281, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32441489

RESUMO

BACKGROUND: Lipoprotein glomerulopathy (LPG) is a rare kidney disease caused by APOE mutations. The aim of this study was to correlate the genetic and clinical features of LPG. METHODS: Totally eight LPG patients were recruited in this study and Sanger sequencing of APOE was performed for all available family members. Clinical and histological features were analyzed. A literature review of LPG was also conducted. RESULTS: Genetic analysis revealed five patients with APOE-Kyoto, two with APOE-Osaka/Kurashiki, and one with APOE-Chicago mutations. LPG patients with urine protein reduced more than 50% had a slower decrease in renal function than those with less urine protein reduction (estimated glomerular filtration rate reduction rate -5.0 ± 0.8 vs. 1.5 ± 0.7 ml/min per 1.73 m2 ⋅month-1 , p = .03). We then enrolled 95 LPG patients from previous studies and this study. LPG patients had higher blood pressure (mean arterial pressure: 109.4 ± 19.4 vs. 94.4 ± 11.1 mmHg, p < .001) than the control group. Interestingly, patients with APOE mutations in the LDL receptor binding region had higher serum apolipoprotein E (apoE) levels [ln(apoE): 2.7 ± 0.4 vs. 2.0 ± 0.5 mg/dl, p < .001] in comparison to other domains. CONCLUSION: Here, we report for the first time APOE-Osaka/Kurashiki and APOE-Chicago mutations in the Chinese population. LPG was associated with higher blood pressure and serum apoE levels were higher in patients with mutations in LDL receptor binding region. In addition, the findings further indicated that treatment of proteinuria might slow down renal function progression in these patients.

13.
ACS Nano ; 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32356971

RESUMO

Graphene aerogels (GAs) with attractive properties have shown tremendous potentials in energy- and environment-related applications. Unfortunately, current assembly methods for GAs such as sol-gel and freeze-casting processes must be conducted in enclosed spaces with unconventional conditions, thus being literally inoperative for in situ and continuous productions. Herein, a direct slurry-casting method at open ambient conditions is established to arbitrarily prepare three-dimensional (3D) porous graphene oxide (GO) bulks without macroscopic dimension limits on a wide range of solid surfaces by retarding Ostwald ripening of 3D liquid GO foams when being dried in air. A subsequent fast thermal reduction (FTR) of GO foams leads to the formation of graphene aerogels (denoted as FTR-GAs) with hierarchical closed-cellular graphene structures. The FTR-GAs show outstanding high-temperature thermal insulation (70% decrease for 400 °C), as well as superelasticity (>1000 compression-recovery cycles at 50% strain), ultralow density (10-28 mg cm-3), large specific surface area (BET, 206.8 m2 g-1), and high conductivity (ca. 100 S m-1). This work provides a viable method to achieve in situ preparations of high-performance GAs as multifunctional structural materials in aircrafts, high-speed trains, or even buildings for the targets of energy efficiency, comfort, and safety.

14.
Chemosphere ; 253: 126693, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32464770

RESUMO

Nitrate pollution presents a serious threat to the environment and public health. As an excellent heterotrophic denitrification carbon source, banana peel (a kind of agricultural waste) provides a feasible alternative to deal with the persistent high concentrations of nitrate pollution. Although the feasibility and economy of banana peel for denitrification have already been reported, the long-term stability and mechanism were still unclear. The coupling mechanism of organic matters and microorganism in the denitrification process was systematically investigated through a 17-cycle experiment. The results showed that significant NO3--N removal load and rate of 164.42 mg/g and 4.69 mg/(L·h) after long-term tests could be obtained. Organic matter analysis and 16S rRNA sequencing showed that the evolution of organic matter was dominated by Anaerolineaceae (fermenting bacteria), and, in the final step, the humification of organic matter was realized. Moreover, the presence of Lentimicrobium (denitrifying bacteria) was indispensable for the continuous removal of high concentrations of nitrate. The main functional gene of nitrogen transformation in this reaction system was NirS (haem-containing). This lab-scale heterotrophic denitrification process could contribute to a better understanding of the carbon and nitrogen cycles in the biogeochemical cycles to some extent, and it also provides a reference for the construction of highly efficient nitrate degradation reactors, based on agricultural wastes.

15.
Clin Exp Med ; 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32253547

RESUMO

Angiopoietin-like protein 2 (Angptl2) plays a key role in chronic inflammation and tissue remodeling. We evaluated whether serum Angptl2 is associated with interstitial lung disease (ILD) in primary Sjogren's syndrome (pSS) patients. A total of 158 consecutive pSS patients and 25 normal healthy controls, which completed lung HRCT, were enrolled in our research. The levels of serum Angptl2 and TGF-ß1 were measured by enzyme-linked immunosorbent assay. We investigated the correlation between the activity indexes of pSS-ILD patients and the serum Angptl2 levels. There were 71 of 158 (44.94%) patients interpreted pSS-ILD by radiologists at the initial presentation. The median interquartile range for serum Angptl2 was 16.55 ng/mL (range 10.82-41.07) in pSS patients, compared with 6.05 ng/mL (range 3.53-9.91) in normal healthy controls (P < 0.001). Importantly, differences between Angptl2 levels in pSS-ILD patients and pSS-N-ILD patients were also statistically significant [29.80 ng/mL (range 15.42-54.40), 14.75 ng/mL (range 9.85-40.48), P < 0.001]. A logistic regression analysis suggested that anti-Ro52, serum Angptl2 and DLCO were associated with pSS patients with interstitial lung disease, with aORs and 95% CIs of 2.06 (1.14-7.65), 4.13 (1.25-15.89) and 9.51 (2.10-37.74), respectively. Moreover, anti-Ro52 (rs = 0.48, P = 0.016) and TGF-ß1 (rs = 0.64, P = 0.003) were significantly correlated with the serum Angptl2 in pSS-ILD patients. And, in pulmonary function tests, the serum Angptl2 was significantly correlated with DLCO (rs = - 0.40, P = 0.009) and FVC (rs = -0.37, P = 0.020). Serum Angptl2 may display a peculiar role in the pathogenesis of pSS-ILD and might be a potential biomarker.

16.
Dalton Trans ; 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32236201

RESUMO

Ni(OH)2 has been widely investigated as a prospective electrode material because of its high theoretical capacitance and relatively low cost. However its synthesis usually needs a complex and lengthy process, and a binder is generally used for fabricating Ni(OH)2 based electrodes. In this work, a self-supporting binder-free ß-Ni(OH)2@nickel foam (NF) integrated electrode was prepared by the in situ growth of ß-Ni(OH)2 on NF using a rapid and facile approach. This approach consists of two processing steps: (1) the pre-treatment of NF with an acid and (2) the quick in situ electrochemical synthesis of ß-Ni(OH)2 on the NF in the KOH electrolyte within half a minute under an applied voltage. The ß-Ni(OH)2@NF integrated electrode possesses a three-dimensional network structure of nanosheet arrays and exhibits excellent electrochemical performance. Its areal capacity is 3.68 mA h cm-2 at a current density of 2 mA cm-2, and the capacity can retain 115.8% of its initial value even after 2000 cycles at a current density of 15 mA cm-2. Moreover, the as-assembled ß-Ni(OH)2@NF//activated carbon (AC) asymmetric supercapacitor (ASC) exhibits a high energy density of 74.2 W h kg-1 with a power density of 776.9 W kg-1 and excellent cycling stability (89.9% retained after 10 000 cycles). This work provides an efficient, facile and economic method for fabricating Ni(OH)2 based integrated electrodes for high-performance supercapacitors.

17.
Chaos ; 30(3): 033101, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32237755

RESUMO

Extreme events appear in many complex nonlinear dynamical systems. Predicting extreme events has important scientific significance and large societal impacts. In this paper, a new mathematical framework of building suitable nonlinear approximate models is developed, which aims at predicting both the observed and hidden extreme events in complex nonlinear dynamical systems for short-, medium-, and long-range forecasting using only short and partially observed training time series. Different from many ad hoc data-driven regression models, these new nonlinear models take into account physically motivated processes and physics constraints. They also allow efficient and accurate algorithms for parameter estimation, data assimilation, and prediction. Cheap stochastic parameterizations, judicious linear feedback control, and suitable noise inflation strategies are incorporated into the new nonlinear modeling framework, which provide accurate predictions of both the observed and hidden extreme events as well as the strongly non-Gaussian statistics in various highly intermittent nonlinear dyad and triad models, including the Lorenz 63 model. Then, a stochastic mode reduction strategy is applied to a 21-dimensional nonlinear paradigm model for topographic mean flow interaction. The resulting five-dimensional physics-constrained nonlinear approximate model is able to accurately predict extreme events and the regime switching between zonally blocked and unblocked flow patterns. Finally, incorporating judicious linear stochastic processes into a simple nonlinear approximate model succeeds in learning certain complicated nonlinear effects of a six-dimensional low-order Charney-DeVore model with strong chaotic and regime switching behavior. The simple nonlinear approximate model then allows accurate online state estimation and the short- and medium-range forecasting of extreme events.

18.
Dalton Trans ; 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32239006

RESUMO

Capacitive deionization (CDI), which is based on ion electrosorption on the surface of electrically charged electrodes, has attracted widespread attention as a novel, cost-effective and environment-friendly desalination technology. Carbon materials are widely used as CDI electrodes due to their high specific surface area (SSA), superior conductivity, and better stability. Many research efforts have been made to further enhance the CDI performance of carbon materials. In this review, the performance-enhancing strategies of various carbon materials including activated carbon, porous carbon, carbon aerogels, carbon nanotubes and graphene are systematically presented. We also explain the significance of the development of CDI technology and identify where further work is urgently required and where challenges are still faced.

19.
Cell Biochem Funct ; 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32266733

RESUMO

Retinoblastoma (RB) is one of the most common primary intraocular malignancies in children. Emerging researches have shown that circular RNAs (circRNAs) play critical roles in a variety of cancers. As a novel circRNA, the function of circ_0000527 in RB remains unknown. In this work, expression level of circ_0000527 and miR-646 in RB tissues and cell lines were detected by quantitative real-time polymerase chain reaction (qRT-PCR). RB cell lines (SO-Rb50 and WERI-Rb-1) were used as cell models in functional experiments. CCK-8 assay, TUNEL assay and transwell assay were employed to detect the biological influence of circ_0000527 and miR-646 on cancer cells in vitro. qRT-PCR, luciferase reporter assay, RIP assay and western blot were used for exploring the interactions among circ_0000527, miR-646 and BCL-2. It was demonstrated that expression level of circ_0000527 in RB samples was significantly up-regulated compared to normal tissues, while miR-646 was markedly down-regulated. Overexpression of circ_0000527 promoted the viability, migration and invasion of RB cells, while miR-646 transfection had the opposite effects. Circ_0000527 sponged miR-646 to regulate the expression of BCL-2. In conclusion, circ_0000527 could promote the development of RB by indirectly modulating BCL-2 via absorbing miR-646. SIGNIFICANCE OF THE STUDY: Expression level of circ_0000527 in RB samples was significantly up-regulated compared to normal tissues, while miR-646 was markedly down-regulated. Overexpression of circ_0000527 promoted the viability, migration and invasion of RB cells, while miR-646 transfection had the opposite effects. Circ_0000527 sponged miR-646 to regulate the expression of BCL-2.

20.
Environ Res ; 185: 109391, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32240841

RESUMO

Denitrifying microbial community can be utilized for eliminating nitrate and Fe(II) combined contamination in groundwater, while excessive amount of Fe(II) limit the process. Natural mineral can be additional substrate for the microbial growth, whereas how it influences the microbial community that mediating the denitrification coupling with Fe(II) oxidation and balancing inhibition of excessive Fe(II) on denitrification remain unclear. In the present study, we conducted a series of microcosm experiments to explore the denitrification and Fe(II) oxidation kinetic, and used RNA-based qPCR and DNA-based high-throughput sequencing to elucidate microbial diversity, co-occurrence and metabolic profiles amended by wheat-rice stone and rock phosphate. The results showed that both minerals could extensively improve and double the denitrification rates (2.0 ± 0.03 to 2.12 ± 0.13 times), decrease the nitrite accumulation and trigger the high resistance of the denitrifiers from the stress of Fe(II), whereas only wheat-rice stone with higher surface area increased the oxidation of Fe(II) (<10%). The addition of both minerals enhanced the microbial alpha-diversity, shaped the beta-diversity and co-occurrence network, and recovered the transcription of nitrate and nitrite reductase (Nar, Nap, NirS, NirK) from the Fe(II) inhibition. Accordingly, heterotroph Methyloversatilis sp., Methylotenra sp. might contribute to the denitrification under wheat-rice stone amendment, Denitratisoma sp. contribute to the denitrification for rock phosphate, and Fe oxidation was partially catalyzed by Dechloromonas sp. or abiotically by the nitrite/nitrous oxide. These findings would be helpful for better understanding the bioremediation of nitrate and Fe contaminated groundwater.

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