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1.
Langmuir ; 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32026679

RESUMO

Painted environmental surfaces are prone to microbiological colonization with potential coating deterioration induced by the microorganisms. Accurate mechanistic models of these interactions require an understanding of the heterogeneity in which the deterioration processes proceed. Here, unsaturated biofilms (i.e., at air/solid interfaces) of the yeast Papiliotrema laurentii were prepared on polyether polyurethane (PEUR) and polyester-polyether polyurethane (PEST-PEUR) coatings and incubated for up to 33 days at controlled temperature and humidity with no additional nutrients. Transmission micro-Fourier transform infrared microscopy (µFTIR) confirmed preferential hydrolysis of the ester component by the biofilm. Atomic force microscopy combined with infrared nanospectroscopy (AFM-IR) was used to analyze initial PEST-PEUR coating deterioration processes at the single-cell level, including underlying surfaces that became exposed following cell translocation. The results revealed distinct deterioration features that remained localized within ∼10 µm or less of the edges of individual cells and cell clusters. These features comprised depressions of up to ∼300 nm with locally reduced ester/urethane ratios. They are consistent with a formation process initiated by enzymatic ester hydrolysis followed by erosion from water condensation cycles. Further observations included particle accumulation in the broader biofilm vicinity. AFM-IR spectroscopy indicated these to be secondary microplastics consisting of urethane-rich oligomeric aggregates. Overall, multiple contributing factors have been identified that can facilitate differential deterioration rates across the PEST-PEUR surface. Effects of the imposed nutrient conditions on Papiliotrema laurentii physiology were also apparent, with cells developing the characteristics of starvation response, despite the availability of polyester metabolites as a carbon source. The combined results provide new laboratory insights into field-relevant microbiological polymer deterioration mechanisms and biofilm physiology at polymer coating interfaces.

2.
BMC Microbiol ; 20(1): 21, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992193

RESUMO

BACKGROUND: Coagulase-negative staphylococci (CoNS) are a group of opportunistic pathogens, which are widely spread in the environment. Animal breeding is an important source of pathogen spreading. However, the concentration and characteristics of CoNS in the bioaerosols of henhouses are unclear. RESULTS: In this study, we showed that CoNS were significantly increased in bioaerosols of henhouses during the first 60 days, and reached 2.0 × 106 CFU/m3, which account for 75.4% of total bacteria. One hundred and two CoNS isolates from bioaerosols and nasal swabs of farmers were further identified, covering seven species. Among these, 41.2% isolates were Staphylococcus sciuri, which was the predominant species, followed by S. equorum, S. saprophyticus, S. haemolyticus, S. xylosus, S. arlettae and S. gallinarum. There were high rates of resistance to oxacillin in CoNS (49.0%), which were defined as Methicillin-Resistant CoNS (MRCoNS), and 36.3% isolates contained resistance gene mecA. Bioaerosol infection models showed that, chickens exposed to aerosolized S. sciuri had significant induction of inflammatory cytokines interleukin (IL)-1ß, IL-6, IL-8 and IL-10 at 5 days post-infection (dpi) in lungs and at 7 dpi in spleens. CONCLUSIONS: We reported a high concentration of CoNS in henhouses, and S. sciuri was the preponderant CoNS species. Antibiotic resistance analysis and bioaerosols infection of CoNS further highlighted its hazards on resistance and immunological challenge. These results suggested that, CoNS in bioaerosols could be one serious factor in the henhouses for not only poultry industry but also public health.

3.
Sci Total Environ ; 704: 135434, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31896223

RESUMO

Ecological floating bed (EFB) has become the preferred technology due to its reputation of green economy, convenience, and efficiency in treating eutrophic landscape water. Based on the statistical analysis of abundant literatures, this paper systematically summarizes the component elements, design parameters, purification mechanism, purification ability, strengthening methods and the correlations among various parameters of EFB, and points out some issues existing in the current research and applications. The results show that the coverage of 5% ~ 38% and water depth of 60 ~ 110 cm should be recommended for EFB design. The microbial transformation-sedimentation contributes mostly to the removal of pollutant, leading to the contribution rate of 51.9% ± 26.4% to nitrogen (N) removal and 50.8% ± 20.4% to phosphorus (P) removal in water respectively. Meanwhile, the average purification abilities of EFB for carbon (C), N and P in water are 4.59 ± 3.82, 0.43 ± 0.35 and 0.04 ± 0.04 g m-2 d-1 respectively. The purification effect is relatively superior when the initial concentration of C, N and P in water is close to C: N: P = 115: 11: 1. In order to enhance the EFB purification efficiency, the methods of artificial aeration, biological chain extension, functional filler introduction, and composite EFB construction can be used. Furthermore, the purification ability of EFB per unit area is correlated positively with water temperature and initial pollutant concentration (r ≥ 0.577, p < 0.01), and correlated negatively with EFB coverage (r ≤ -0.598, p < 0.01). The future research of EFB should focus on enhancing its purification efficiency and seasonal adaptability, studying the mechanism of algae inhibition by allelochemicals, and exploring the harvesting management and resource utilization of plants. This paper provides more reasonable design parameters, feasible management strategies and prospective research directions for environmental managers and researchers who would like to adopt EFB to purify eutrophic landscape water.

4.
Sci Rep ; 10(1): 435, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949256

RESUMO

The aphid Schlechtendalia chinensis(Bell) induces horned galls on their primary host Rhus chinensis(Mill). These galls serve as closed habitats to support thousands of aphids per gall. Ecological parameters inside a gall are unknown. In this study, we showed that the microclimate inside galls was reltively stable, with nearly 100% humidity and 30-50 lux light regardless of outside environmental conditions. Gall-residing aphids produce waste gas and honeydew. A gall contained 26 organic volatiles inside with acetic acid as the largest component. Honeydew is rich in sugars and may provide nutrients for microbial growth. However, no evidence for pathogenic microorganisms was found inside a gall. The acidic environment in a gall may curb microbial growth. On the secondary host, the moss Plagiomnium maximoviczii (Lindb.) T. J. Kop., the microclimate is unstable and humidity fluctuated at 45~100%, while light ranged from 150 to 500 lux on different environmental conditions. Aphid alternated in two different habitats, the gall generation increased from a single fundatrix to thousands of aphids, however, survival rate of the moss generation is less 3%. A comparison of the environmental traits between gall and moss revealed that a stable habitat with dark and moist is advantageous for aphid reproduction.

5.
J Agric Food Chem ; 68(5): 1354-1363, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31933364

RESUMO

Carotenoids are essential phytonutrients synthesized by all photosynthetic organisms. Acyclic lycopene is the first branching point for carotenoid biosynthesis. Lycopene ß- and ε-cyclases (LCYB and LCYE, respectively) catalyze the cyclization of its open ends and direct the metabolic flux into different downstream branches. Carotenoids of the ß,ß-branch (e.g., ß-carotene) are found in all photosynthetic organisms, but those of the ß,ε-branch (e.g., lutein) are generally absent in cyanobacteria, heterokonts, and some red algae. Although both LCYBs and LCYEs have been characterized from land plants, there are only a few reports on LCYs from cyanobacteria and algae. Here, we cloned four LCY genes from Porphyra umbilicalis and Pyropia yezoensis (susabi-nori) of Bangiales, the most primitive red algal order that synthesizes lutein. Our functional characterization in both Escherichia coli and Arabidopsis thaliana demonstrated that each species has a pair of LCYB and LCYE. Similar to LCYs from higher plants, red algal LCYBs cyclize both ends of lycopene, and their LCYEs only cyclize a single end. The characterization of LCYEs from red algae resolved the first bifurcation step toward ß-carotene and lutein biosynthesis. Our phylogenetic analysis suggests that LCYEs of the green lineage and the red algae originated separately during evolution.

6.
J Environ Sci (China) ; 87: 82-92, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31791520

RESUMO

Pot experiments were conducted to evaluate the effect of water management, namely continuous flooding (CF), intermittent flooding (IF) and non-flooding (NF), on Cd phytoavailaility in three paddy soils that differed in pH and in Cd concentrations. Diffusive gradients in thin films (DGT) technique was employed to monitor soil labile Cd and Fe concentrations simultaneously at three growth stages (tillering, heading and mature stage) of rice. The Cd phytoavailability were generally in the order of NF > IF > CF, and higher rice Cd (over permitted level, 0.2 mg/kg) were only found in neutral and acidic soils under NF conditions. DGT measured soil labile Cd rather than total Cd was the most reliable predictor for Cd accumulation in rice. CF enhanced the formation of root plaques, which related to oxidation of large quantities of available Fe on root surfaces due to the O2 secretion of rice root. The Cd concentration in root plaques shared the same trend with DGT-Cd. Generally, root plaques would inhibit Cd uptake by rice under CF conditions, while under IF and NF conditions, root plaques act as a temporarily store of Cd, and soil labile Cd is the key factor that controls the transfer of Cd from soil to rice. The results of principle component analysis revealed that water management had the greatest effect on soil Cd lability and rice Cd in acidic soil. Thus, it is important to consider the availability of Cd and soil pH when assessing current agricultural practices of contaminated soil in China.


Assuntos
Cádmio/análise , Oryza , Rizosfera , Poluentes do Solo/análise , Agricultura , China , Concentração de Íons de Hidrogênio
7.
Antibiotics (Basel) ; 8(4)2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783564

RESUMO

Rediscovery of known antibiotics from actinobacteria, especially Streptomyces, has become a bottleneck issue. Nowadays, more specific identification and dereplication could be acquired by a combination of modern analytic techniques with various databases. In this study, 261 actinobacterial strains were isolated from 8 mangrove soil samples by culture-dependent method. A total of 83 strains were selected to evaluate antibacterial activities and mechanisms by disc diffusion method and a unique double fluorescent protein reporter system (pDualrep2), respectively. Thirty-two strains exhibited antagonistic activity against at least one of the "ESKAPE" pathogens. Four Streptomyces strains (B475, B486, B353, and B98) showed strong inhibitory activity against Gram-positive bacteria and induced DNA damage SOS response. One Micromonospora strain (B704) exhibited inhibitory activity against several pathogens and induced attenuation-based translational inhibitors reporter. Seven members of quinoxaline-type antibiotics including quinomycin A, quinomycin monosulfoxide, and other five putative new analogues were found from the culture broth of strain B475 by a combination of anti-MRSA guide, HPTLC, HPLC-UV, and UPLC-UV-HRESIMS/MS analysis, Chemspider searching, and MS/MS-based molecular networking analysis. In conclusion, this study not only demonstrated that mangrove is a rich source of actinobacteria with the potentially new antibiotics but showed rapid dereplication of known antibiotics in the early stage can improve efficiency for the discovery of new antibiotics.

8.
Insects ; 10(12)2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31795150

RESUMO

Lac is a type of natural resin secreted by lac insects and is widely used in the military and other industries because of its excellent adhesion and insulation properties. The main ingredients of lac are lactones and lactides, which are formed from hydroxy fatty acids and sesquiterpene esters. In this study, we measured lac secretion rates by the insect Kerria chinensis at different developmental stages and identified lac secretion-minimum and lac secretion-active stages of the insect. We then analyzed transcriptomes of lac secretion-minimum and lac secretion-active stages of the insect. Based on expression profiles of genes in different stages of the insect, we identified pathways and genes that are potentially involved in lac synthesis and secretion in K. chinensis. Our study lays a foundation for future studies to reveal the molecular mechanisms and pathways of lac synthesis and secretion in this beneficial insect.

9.
J Intensive Care ; 7: 54, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827802

RESUMO

Background: A spontaneous breathing trial (SBT) is a major diagnostic tool to predict successfully extubation in patients. Several factors may lead to weaning failure, including the degree of lung aeration loss and diaphragm dysfunction. The main objective was to compare the diaphragmatic contractility between patients with high lung aeration loss and low lung aeration loss during a 30-minute SBT by ultrasound. Methods: This was a prospective single-center study. Lung ultrasound aeration score (LUS) and diaphragmatic thickening fraction (DTF) were measured during mechanical ventilation 1 h before SBT (T-1), 30 min (T1), and 120 min (T2) after the start of the SBT during quiet breathing. The right and left DTF were compared between patients with LUS ≥ 14 (high lung aeration loss), considered at high risk of post-extubation distress, and those with LUS < 14 (low lung aeration loss). The relationship between the LUS and DTF and the changes in LUS and DTF from T-1 to T2 in patients with LUS ≥ 14 were assessed. Results: Forty-nine patients were analyzed; 33 had LUS ≥ 14 and 16 had LUS < 14 at T1. The DTF at T1 was significantly higher in patients with LUS ≥ 14 than in those with LUS < 14: the right median (IQR) DTF was 22.2% (17.1 to 30.9%) vs. 14.8% (10.2 to 27.0%) (p = 0.035), and the left median (IQR) DTF was 25.0% (18.4 to 35.0%) vs. 18.6% (9.7 to 24.2%) (p = 0.017), respectively. There was a moderate positive correlation between the LUS and the DTF (Rho = 0.3, p = 0.014). A significant increase in the LUS was observed from T-1 to T1, whereas no change was found between T1 and T2. The DTF remained stable from T-1 to T2. Conclusions: During a SBT, diaphragmatic contraction acts differently depending on the degree of pulmonary aeration. In patients with high lung aeration loss, increased diaphragmatic contractility indicates an additional respiratory effort to compensate lung volume loss that would contribute to successful SBT. Further studies are needed to evaluate the combined evaluation of lung aeration and diaphragmatic function to predict the successful weaning of patients from mechanical ventilation.

10.
JAMA Intern Med ; 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31841577

RESUMO

Importance: The role of herpes simplex virus (HSV) reactivation on morbidity and mortality in patients in the intensive care unit requiring mechanical ventilation remains unknown. Objective: To determine whether preemptive treatment with intravenous acyclovir reduces the duration of mechanical ventilation in patients with HSV oropharyngeal reactivation. Design, Setting, and Participants: A double-blind, placebo-controlled randomized clinical trial was conducted in 16 intensive care units in France. Participants included 239 adults (age, >18 years) who received mechanical ventilation for at least 96 hours and continued to receive mechanical ventilation for 48 hours or more, with HSV oropharyngeal reactivation. Patients were enrolled between February 2, 2014, and February 22, 2018. Interventions: Participants were randomized to receive intravenous acyclovir, 5 mg/kg, 3 times daily for 14 days or a matching placebo. Main Outcomes and Measures: The primary end point was ventilator-free days from randomization to day 60. Prespecified secondary outcomes included mortality at 60 days. Main analyses were conducted on an intention-to-treat basis. Results: Of 239 patients enrolled and randomized, 1 patient withdrew consent, leaving 238 patients, with 119 patients in both the acyclovir and placebo (control) groups (median [IQR] age, 61 [50-70] years; 76 [32%] women) available for primary outcome measurement. On day 60, the median (IQR) numbers of ventilator-free days were 35 (0-53) for acyclovir recipients and 36 (0-50]) for controls (P = .17 for between-group comparison). Among secondary outcomes, 26 patients (22%) and 39 patients (33%) had died at day 60 (risk difference, 0.11, 95% CI, -0.004 to 0.22, P = .06). The adverse event frequency was similar for both groups (28% in the acyclovir group and 23% in the placebo group, P = .40), particularly acute renal failure post randomization affecting 3 acyclovir recipients (3%) and 2 controls (2%). Four patients (3%) in the acyclovir group vs none in the placebo group stopped the study drug for treatment-related adverse events. Conclusions and Relevance: In patients receiving mechanical ventilation for 96 hours or more with HSV reactivation in the throat, use of acyclovir, 5 mg/kg, 3 times daily for 14 days, did not increase the number of ventilator-free days at day 60, compared with placebo. These findings do not appear to support routine preemptive use of acyclovir in this setting. Trial Registration: ClinicalTrials.gov identifier: NCT02152358.

11.
BMC Med Genomics ; 12(Suppl 8): 193, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31856831

RESUMO

BACKGROUND: An important task in the interpretation of sequencing data is to highlight pathogenic genes (or detrimental variants) in the field of Mendelian diseases. It is still challenging despite the recent rapid development of genomics and bioinformatics. A typical interpretation workflow includes annotation, filtration, manual inspection and literature review. Those steps are time-consuming and error-prone in the absence of systematic support. Therefore, we developed GTX.Digest.VCF, an online DNA sequencing interpretation system, which prioritizes genes and variants for novel disease-gene relation discovery and integrates text mining results to provide literature evidence for the discovery. Its phenotype-driven ranking and biological data mining approach significantly speed up the whole interpretation process. RESULTS: The GTX.Digest.VCF system is freely available as a web portal at http://vcf.gtxlab.com for academic research. Evaluation on the DDD project dataset demonstrates an accuracy of 77% (235 out of 305 cases) for top-50 genes and an accuracy of 41.6% (127 out of 305 cases) for top-5 genes. CONCLUSIONS: GTX.Digest.VCF provides an intelligent web portal for genomics data interpretation via the integration of bioinformatics tools, distributed parallel computing, biomedical text mining. It can facilitate the application of genomic analytics in clinical research and practices.

12.
Environ Sci Pollut Res Int ; 26(36): 37070-37081, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31745766

RESUMO

The anoxic and reductive aquatic environment is formed easily in summer due to the global warming, which may accelerate endogenous release. In this experiment, four different dosages of calcium peroxide (CaO2) were adopted to study the control effects of nutrients release from the sediments in the simulated landscape waters. The results demonstrated that CaO2 addition could effectively improve the physicochemical properties and microbial composition in sediments, and an obvious improvement was achieved with a larger dosage. It was observed that the surface sediments of experiment groups were oxidized to form a capping barrier between the sediment and overlying water, which might cut off the pollutant diffusion in sediment. Meanwhile, CaO2 could decrease the nutrients concentration in water obviously, and the reduced effect was positively correlated with the CaO2 dosage. Compared with the nutrients release fluxes in CK (105.89 mg-TN m-2 day-1, 106.48 mg-NH4+-N m-2 day-1, 4.14 mg-TP m-2 day-1, and 4.30 mg-SRP m-2 day-1), the CaO2 dosages of 0.12 and 0.18 kg m-2 could entirely inhibit the nutrients release from sediment, and partially reduce the original pollutants in the overlying water. However, 0.18 kg m-2 CaO2 would cause a higher increase of pH value and NO2--N concentration, and bring potential risk to the aquatic ecosystem. Therefore, 0.12 kg-CaO2 m-2-sediment was selected as the optimal dosage by considering the control effect, economic cost, and potential risk comprehensively. In general, this study provided a quantitative usage method of CaO2, which is convenient and effective to prevent or control the nutrients release from sediment caused by anoxic and reductive condition in summer.

13.
Am J Transl Res ; 11(9): 5728-5739, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632543

RESUMO

BRD4, a member of the bromodomain and extraterminal domain (BET) family and an important epigenetic reader, has emerged as an attractive oncology target. Cholangiocarcinoma is a lethal neoplasm without approved targeted therapies. BET bromodomain inhibitors have shown promising effects in certain cancers including cholangiocarcinoma. Recently developed BRD4 Proteolysis Targeting Chimera (PROTAC) compounds lead to fast and efficient degradation of BRD4 and provides longer-lasting effect than small molecule BRD4 inhibitors. In this study, we investigated the antitumor effect of a newly developed BRD4 degrader ARV-825 in cholangiocarcinoma. Immunohistochemistry and Western blotting were used to determine the expression level of BRD4. CCK-8 assay and BrdU ELISA assay were used to assess cell proliferation. Caspase 3/7 activity and Annexin V/PI staining were used to assess apoptosis. We demonstrated that BRD4 expression was elevated in cholangiocarcinoma tissues compared to normal bile duct or surrounding normal liver tissues. ARV-825 produced fast and long-lasting loss of BRD4 protein, resulting in more inhibition of CCA cell proliferation and induction of apoptosis than BRD4 inhibitors OTX-015 and JQ1. C-Myc is a well-known downstream target of BRD4. We found that ARV-825 suppressed c-Myc levels more effectively than BRD4 inhibitors. However, ARV-825 did not inhibit c-Myc expression in CCA cells with low basal c-Myc levels. Further analysis showed that ARV-825 significantly upregulated p21 expression and arrested cell cycle progression at G1 phase. In conclusion, BRD4 degrader ARV-825 leads to rapid and sustained degradation of BRD4 and is effective against cholangiocarcinoma.

14.
Crit Care Med ; 47(12): e953-e961, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31567524

RESUMO

OBJECTIVES: The association between outcome and kidney injury detected at discharge from the ICU using different biomarkers remains unknown. The objective was to evaluate the association between 1-year survival and kidney injury at ICU discharge. DESIGN: Ancillary investigation of a prospective observational study. SETTING: Twenty-one ICUs with 1-year follow-up. PATIENTS: Critically ill patients receiving mechanical ventilation and/or hemodynamic support for at least 24 hours were included. INTERVENTIONS: Serum creatinine, plasma Cystatin C, plasma neutrophil gelatinase-associated lipocalin, urinary neutrophil gelatinase-associated lipocalin, plasma Proenkephalin A 119-159, and estimated glomerular filtration rate (on serum creatinine and plasma Cystatin C) were measured at ICU discharge among ICU survivors. MEASUREMENTS AND MAIN RESULTS: The association between kidney biomarkers at discharge and mortality was estimated using logistic model with and without adjustment for prognostic factors previously identified in this cohort. Subgroup analyses were performed in patients with discharge serum creatinine less than 1.5-fold baseline at ICU discharge. Among 1,207 ICU survivors included, 231 died during the year following ICU discharge (19.2%). Estimated glomerular filtration rate was significantly lower and kidney injury biomarkers higher at discharge in nonsurvivors. The association between biomarker levels or estimated glomerular filtration rate and mortality remained after adjustment to potential cofounding factors influencing outcome. In patients with low serum creatinine at ICU discharge, 25-47% of patients were classified as subclinical kidney injury depending on the biomarker. The association between kidney biomarkers and mortality remained and mortality was higher than patients without subclinical kidney injury. The majority of patients who developed acute kidney injury during ICU stay had elevated biomarkers of kidney injury at discharge even with apparent recovery based on serum creatinine (i.e., subclinical acute kidney disease). CONCLUSIONS: Elevated kidney biomarkers measured at ICU discharge are associated with poor 1-year outcome, including in patients with low serum creatinine at ICU discharge.

15.
Cancer Med ; 8(15): 6730-6740, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31512408

RESUMO

BRCA1, a multifunctional protein with an important role in DNA double-strand break repair by homologous recombination (HR), is subjected to ubiquitin-dependent degradation. To date, several E3 ubiquitin ligases have been identified to govern BRCA1 stability, but the deubiquitinase that counteracts its turnover remains undefined. In this study, we report that the ubiquitin-specific protease 9X (USP9X) is a bona fide deubiquitinase for BRCA1 in human cancer cells. Reciprocal immunoprecipitation assays demonstrated that USP9X interacted with BRCA1. Depletion of USP9X by short interfering RNAs or inhibition of USP9X by the small-molecular inhibitor WP1130 significantly reduced BRCA1 protein abundance, without affecting its mRNA levels. In contrast, overexpression of wild-type USP9X, but not its deubiquitinase activity-defective mutant (C1566S), resulted in an upregulation of BRCA1 protein levels. Moreover, USP9X depletion reduced the half-life of BRCA1, accompanied by an increase in its ubiquitination. HR assays showed that knockdown of USP9X significantly reduced HR efficiency, which was partially rescued by reintroduction of BRCA1 into USP9X-depleted cells. In support of these findings, USP9X knockdown significantly enhanced sensitivity to PARP inhibitor Olaparib and methyl methanesulfonate (MMS). Collectively, these results establish USP9X as a deubiquitinase for BRCA1 and reveal a previously unrecognized role of USP9X in the regulation of HR repair and the sensitivity of cancer cells to DNA-damaging agents.

16.
Environ Pollut ; 255(Pt 2): 112989, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546078

RESUMO

Large-area hypoxia of urban landscape water often causes the emissions of harmful gases in summer, which not only reduces its sensory effects, but also brings a potential threat to aquatic ecosystem and human health. This study explored the dose effects of calcium peroxide (CaO2) on inhibiting harmful gases emissions and restoring the scenic effect (including visual sense and olfactory sense) of anoxic/anaerobic landscape water system. The results indicated that the emissions of H2S, CO2 and CH4 from the anoxic/anaerobic water system were obviously inhibited in the reactors with CaO2 additions and the effect was positively correlated with the CaO2 dose. Meanwhile, the concentrations of total chemical oxygen demand (TCOD) and soluble sulfide (S2-), and turbidity in the overlying water (the water-layer above the sediment-water interface) were also decreased in the reactors dosed with CaO2. The reason was ascribed to the improvement of the anoxic/anaerobic condition in the water system and the increase of the species richness, bacteria count and aerobic microorganism abundance in sediment. Furthermore, 0.12 kg-CaO2 m-2-sediment was selected as the optimal dose, which was based on considering the inhibiting effect of the harmful gases emissions, comprehensive influence and costs. Compared with control check (CK, the reactor without adding CaO2), the optimal dose of CaO2 could reduce 75.10% CH4, 81.02% CO2 and 100% H2S in gases, and decrease 81.52% S2-, 42.85% TCOD and 84.01% turbidity in the overlying water. In conclusion, all the dosages of CaO2 could improve the anoxic condition of water system and 0.12 kg-CaO2 m-2-sediment was the optimal dose in inhibiting harmful gases emissions, which could keep an excellent water quality in this simulation experiment. Therefore, this study may provide a feasible method and the optimal dose for inhibiting the emissions of harmful gases and restoring the scenic effect in the similar anoxic/anaerobic landscape water.


Assuntos
Peróxidos/análise , Poluentes Químicos da Água/análise , Anaerobiose , Ecossistema , Gases , Hipóxia , Água , Qualidade da Água
17.
Materials (Basel) ; 12(16)2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31395796

RESUMO

We present a low-noise photodetector based on van der Waals stacked black phosphorus (BP)/boron nitride (h-BN)/graphene tunneling junctions. h-BN acts as a tunneling barrier that significantly blocks dark current fluctuations induced by shallow trap centers in BP. The device provides a high photodetection performance at mid-infrared (mid-IR) wavelengths. While it was found that the photoresponsivity is similar to that in a BP photo-transistor, the noise equivalent power and thus the specific detectivity are nearly two orders of magnitude better. These exemplify an attractive platform for practical applications of long wavelength photodetection, as well as provide a new strategy for controlling flicker noise.

18.
Cell Death Differ ; 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31406303

RESUMO

Deregulation of E3 ubiquitin ligases is intimately implicated in breast cancer pathogenesis and progression, but the underlying mechanisms still remain elusive. Here we report that RING finger protein 144A (RNF144A), a poorly characterized member of the RING-in-between-RING family of E3 ubiquitin ligases, functions as a tumor suppressor in breast cancer. RNF144A was  downregulated in a subset of primary breast tumors and restoration of RNF144A suppressed breast cancer cell proliferation, colony formation, migration, invasion in vitro, tumor growth, and lung metastasis in vivo. In contrast, knockdown of RNF144A promoted malignant phenotypes of breast cancer cells. Quantitative proteomics and biochemical analysis revealed that RNF144A interacted with and targeted heat-shock protein family A member 2 (HSPA2), a putative oncoprotein that is frequently upregulated in human cancer and promotes tumor growth and progression, for ubiquitination and degradation. Notably, the ligase activity-defective mutants of RNF144A impaired its ability to induce ubiquitination and degradation of HSPA2, and to suppress breast cancer cell proliferation, migration, and invasion as compared with its wild-type counterpart. Moreover, RNF144A-mediated suppression of breast cancer cell proliferation, migration, and invasion was rescued by ectopic HSPA2 expression. Clinically, low RNF144A and high HSPA2 expression in breast cancer patients was correlated with aggressive clinicopathological characteristics and decreased overall and disease-free survival. Collectively, these findings reveal a previously unappreciated role for RNF144A in suppression of breast cancer growth and metastasis, and identify RNF144A as the first, to our knowledge, E3 ubiquitin ligase for HSPA2 in human cancer.

19.
ACS Omega ; 4(7): 12938-12947, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31460420

RESUMO

Flow-through optical chromatography (FT-OC), an advanced mode of optical chromatography, achieved baseline separation of a mixture of silica microparticles (SiO2, 1.00 and 2.50 µm) and a mixture of polystyrene microparticles (PS, 1.00, 2.00, and 3.00 µm) based on particle size. Comparisons made between experimentally determined velocities for the microparticles and theoretically derived velocities from Mie theory and Stokes' law validated the data collection setup and the data analysis for FT-OC. A population shift in live macrophages (cell line IC-21, ATCC TIB-186) responding to environmental stimuli was sensitively detected by FT-OC. The average velocity of macrophages stressed by nutritional deprivation was decreased considerably together with a small but statistically significant increase in cell size. Mie scattering calculations demonstrated that the small increase in cell size of macrophages stressed by nutritional deprivation was not entirely responsible for this decrease. Confocal fluorescence microscopy and atomic force microscopy (AFM) studies revealed morphological changes of macrophages induced by nutritional deprivation, and these changes were more likely responsible for the decrease in average velocity detected by FT-OC. Confocal Raman microspectroscopy was used to shed light upon biochemical transformations of macrophages suffering from nutritional deprivation.

20.
Respir Care ; 64(12): 1478-1487, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31431563

RESUMO

BACKGROUND: The value of ultrasound in assessing lung aeration of patients with ARDS who require venovenous extracorporeal membrane oxygenation (ECMO) has, to our knowledge, never been studied. The objective of the study was to evaluate by using ultrasound lung aeration at ECMO initiation and withdrawal in subjects with severe ARDS supported by venovenous ECMO. METHODS: Fifty subjects were included in this pilot retrospective study. The lung ultrasound aeration score (LUS) and respiratory variables were collected at ECMO initiation (T0) and ECMO withdrawal (T1). The LUS at T0 between the subjects who survived to ICU discharge and those who died in ICU was compared. The relationship between changes in LUS and changes in PaO2 /FIO2 from T0 to T1 was assessed. RESULTS: The ICU mortality was 34%. The LUS at T0 did not differ between survivors and non-survivors (median 22 [interquartile range] {IQR} 19-26 vs median 24 [IQR, 19-28]; P = .60). From T0 to T1, the LUS decreased significantly in survivors (median 22 [IQR, 19-26] vs median 16 [IQR, 13-19]; P < .001), it decreased moderately in non-survivors who were weaned off ECMO (median 26 [24-29]) vs median 22 (IQR, 17-24), P = .031), and remained stable in those who died during ECMO (median 25 [IQR, 19-29] vs median 25 [IQR, 23-31]; P = .22). Changes in PaO2 /FIO2 were not related to changes in the LUS between T0 and T1. CONCLUSIONS: At the time of ECMO placement, the subjects who survived ARDS had aeration loss close to that observed in the subjects who did not survive. At the time of ECMO withdrawal, there was a significant improvement in lung aeration in the survivors, whereas a severe loss of lung aeration persisted in the non-survivors, although some were weaned off ECMO. Lung ultrasound provided a valuable tool for bedside assessment of lung aeration in subjects supported by ECMO.

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