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1.
Bone ; 133: 115258, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32018039

RESUMO

Steroid-induced osteonecrosis of the femoral head (SONFH) is a common debilitating orthopedic disease. The bone marrow mesenchymal stem cells (BMSCs) are a type of mesenchymal stem cells which play crucial roles in bone repair. The adipogenic/osteogenic differentiation disorder of BMSCs has been widely perceived contributing to SONFH. However, the regulatory mechanism of BMSCs differentiation disorder still remains unclear. Circular RNA (circRNA), a kind of stable ncRNA, plays important roles in regulating gene expression via various ways. To date, there are no studies to uncover the circRNA expression profile and screen out the key circRNAs playing crucial roles in adipogenic/osteogenic differentiation disorder of SONFH-BMSCs. In present study, we detected the circRNA expression profiles in SONFH-BMSCs for the first time. A total of 820 circRNAs were differentially expressed in SONFH-BMSCs, including 460 up- and 360 down-regulated circRNAs. Bioinformatics analysis indicates circRNA CDR1as, one up-regulated circRNA, may play crucial role in adipogenic/osteogenic differentiation disorder of SONFH-BMSCs via CDR1as-miR-7-5p-WNT5B axis. Knocking-down CDR1as resulted in increasing of osteogenic differentiation and decreasing of adipogenic differentiation of BMSCs, while over-expressing CDR1as resulted in decreasing of osteogenic differentiation and increasing of adipogenic differentiation of BMSCs. The miR-7-5p binding sites of CDR1as and WNT5B were verified by luciferase reporter gene assay. Our study may provide new insights into the molecular mechanisms of osteogenic/adipogenic differentiation disorder of SONFH-BMSCs and new biomarkers for the diagnosis and treatment of SONFH.

2.
Allergy ; 2020 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-32064642

RESUMO

Allergic asthma is a frequent asthma phenotype. Both IgE and type 2 cytokines are increased, with some degree of overlap with other phenotypes. Systematic reviews assessed the efficacy and safety of benralizumab, dupilumab and omalizumab (alphabetical order) versus standard of care for patients with uncontrolled severe allergic asthma. Pubmed, EMBASE and Cochrane Library were searched to identify RCTs and health economic evaluations, published in English. Critical and important asthma-related outcomes were evaluated. The risk of bias and the certainty of the evidence were assessed using GRADE. All three biologicals reduced with high certainty the annualised asthma exacerbation rate: benralizumab incidence rate ratios (IRR) 0.63 (95% CI 0.50-0.81); dupilumab IRR 0.58 (95%CI 0.47-0.73); omalizumab IRR 0.56 (95%CI 0.42-0.73). Benralizumab and dupilumab improved asthma control with high certainty and omalizumab with moderate certainty, however none reached the minimal important difference (MID). Both benralizumab and omalizumab improved QoL with high certainty, but only omalizumab reached the MID. Omalizumab enabled ICS dose reduction with high certainty. Benralizumab and omalizumab showed an increase in drug-related adverse events (AEs) with low to moderate certainty. All three biologicals had moderate certainty for an ICER/QALY value above the willingness to pay threshold. There was high certainty that in children 6-12 years old omalizumab decreased the annualised exacerbation rate [IRR 0.57 (95%CI 0.45-0.72)], improved QoL [relative risk 1.43 (95%CI 1.12 -1.83)], reduced ICS [mean difference (MD) -0.45 (95% CI -0.58 to -0.32)] and rescue medication use [ MD -0.41 (95%CI -0.66 to -0.15)].

3.
Bioresour Technol ; 303: 122947, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32045865

RESUMO

Enhanced macroalgal biochars with large specific surface areas (up to 399 m2 g-1), partly graphitized structure, high nitrogen doping (up to 6.14%), and hydrophobicity were fabricated by co-carbonization of macroaglae, ferric chloride, and zinc chloride. These biochars were used as sorbents for the removal of polycyclic aromatic hydrocarbons from water. The sorption capacity of polycyclic aromatic hydrocarbons onto macroalgal biochars was high (up to 90 mg g-1), and recycling by thermal desorption was practicable. We revealed the physical-dominated multilayer sorption process, based on results from characterization and sorption experiments. Pore filling, mass transfer, π-π stacking, and the partition effect were found to be possible sorption mechanisms. This study suggests that porous graphitized nitrogen-doped biochars may be synthesized from macroalgae with simple one-pot carbonization and display promising applicability for sorption removal of organic pollutants from water.

4.
Tree Physiol ; 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32031640

RESUMO

The copper chaperone ATX1 has been investigated previously in the herbaceous plants Arabidopsis and rice. However, the molecular mechanisms of ATX1 underlying copper transport and functional characteristics in the woody plant Populus are poorly understood. In this study, PnATX1 and PnATX2 of Populus simonii × P. nigra were identified and characterized. Sequence analysis showed that PnATXs contained the metal-binding motif MXCXXC in the N-terminus and a lysine-rich region. Phylogenetic analysis of ATX protein sequences revealed that PnATXs were clustered in the same group as AtATX1. PnATX proteins were localized in the cytoplasm and nucleus. Tissue-specific expression analysis showed that PnATX1 and PnATX2 were expressed in all analyzed tissues and, in particular, expressed to a higher relative expression level in young leaves. Quantitative real-time PCR analysis indicated that each PnATX gene was differentially expressed in different tissues under treatments with copper, zinc, iron, jasmonate, and salicylic acid. The copper-response element GTAC, methyl jasmonate and salicylic acid responsiveness elements, and other cis-acting elements were identified in the PnATX1 and PnATX2 promoters. Expression of ß-glucuronidase driven by the PnATX1 promoter was observed in the apical meristem of 7-day-old Arabidopsis transgenic seedlings, and the signal strength was not influenced by deficient or excessive copper conditions. Both PnATX1 and PnATX2 functionally rescued the defective phenotypes of yeast atx1Δ and sod1Δ strains. Under copper excess and deficiency conditions, transgenic Arabidopsis atx1 mutants harboring 35S::PnATX constructs exhibited root length and fresh weight similar to those of the wild type and higher than those of Arabidopsis atx1 mutants. Superoxide dismutase activity decreased in transgenic lines compared with that of atx1 mutants, whereas peroxidase and catalase activities increased significantly under excess copper. The results provide a basis for elucidating the role of Populus PnATX genes in copper homeostasis.

5.
Allergy ; 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32034960

RESUMO

Five biologicals have been approved for severe eosinophilic asthma, a well-recognised phenotype. Systematic reviews (SR) evaluated the efficacy and safety of benralizumab, dupilumab, mepolizumab, omalizumab and reslizumab (alphabetical order) compared to standard of care for severe eosinophilic asthma. Pubmed, EMBASE and Cochrane Library were searched to identify RCTs and health economic evaluations, published in English. Critical and important asthma-related outcomes were evaluated for each of the biologicals. The risk of bias and the certainty of the evidence were assessed using GRADE. 19 RCTs (3 RCTs for benralizumab, 3 RCTs for dupilumab, 3 RCTs for mepolizumab, 4 RCTs for omalizumab, and 5 RCTs for reslizumab), including subjects 12 to 75 years old (except for omalizumab including also subjects 6-11 years old), ranging from 12 to 56 weeks were evaluated. All biologicals reduce exacerbation rates with high certainty of evidence: benralizumab rate ratio (RR) 0.53 (95% CI 0.39 to 0.72), dupilumab RR 0.43 (95% CI 0.32 to 0.59), mepolizumab RR 0.49 (95% CI 0.38 to 0.66), omalizumab RR 0.56 (95% CI 0.40 to 0.77), and reslizumab RR 0.46 (95% CI 0.37 to 0.58). Benralizumab, dupilumab and mepolizumab reduce the daily dose of oral corticosteroids (OCS) with high certainty of evidence. All evaluated biologicals probably improve asthma control, QoL and FEV1 , without reaching the minimal important difference (moderate certainty). Benralizumab, mepolizumab and reslizumab slightly increase drug-related adverse events (AE) and drug-related serious AE (low to very low certainty of evidence). The incremental cost-effectiveness ratio per quality adjusted life-years value is above the willingness to pay threshold for all biologicals (moderate certainty). Potential savings are driven by decrease in hospitalisations, emergency and primary care visits. There is high certainty that all approved biologicals reduce the rate of severe asthma exacerbations and for benralizumab, dupilumab and mepolizumab for reducing OCS. There is moderate certainty for improving asthma control, QoL, FEV1 and cost-effectiveness. More data on long term safety are needed together with more efficacy data in the paediatric population.

6.
Plant Cell Environ ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32012302

RESUMO

The circadian pacemaker in plants is a hierarchical multioscillator system that directs and maintains a 24-hr oscillation required for organism homeostasis and environmental fitness. Molecular clockwork within individual tissues and organs acts cell autonomously, showing differences in circadian expression of core oscillators and their target genes; there are functional dominance and coupling in the complex regulatory network. However, molecular characteristics of organ-specific clocks are still unknown. Here, we showed the detached shoot and root possess dynamic circadian protein-protein interactions between clock core components, periodicity in organs exhibits a difference. The period length difference between shoot and root was not remarkable in prr7-3 and prr7-3 prr9-1 mutants. In addition, the phase transition curve indicated that shoot and root clock respond differently to the resetting cues of ambient temperature. PRR9 and PRR7 compensate circadian period between 22°C and 28°C in shoot, not in root. The circadian rhythms of PRR9 or PRR7 transcript accumulation showed no difference at 22°C and 28°C in shoot, but differences were observed in root. In summary, our results reveal the specificity of dynamic circadian protein-protein interactions in organ-autonomous clocks and the critical roles of PRR9 and PRR7 in mechanisms regulating temperature compensation in aerial shoot system.

7.
J Am Coll Cardiol ; 75(1): 93-112, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31918838

RESUMO

The National Cardiovascular Data Registry PINNACLE (Practice Innovation and Clinical Excellence) Registry is the largest outpatient cardiovascular practice registry in the world. It tracks real-world management and quality of 4 common cardiovascular conditions: heart failure, coronary artery disease, atrial fibrillation, and hypertension. In 2013, the PINNACLE Registry contained information on 2,898,505 patients, cared for by 4,859 providers in 431 practices. By 2017, the registry contained information on 6,040,996 patients, cared for by 8,853 providers in 724 practices. During this time period, care processes for PINNACLE patients generally improved. Among patients with heart failure, combined beta-blocker and renin-angiotensin antagonist medication rates increased from 60.7% to 72.8%. Among patients with coronary artery disease, statin medication rates increased from 66% to 80.1%. Among patients with atrial fibrillation, oral anticoagulation rates increased from 52.7% to 65.2%. In contrast, blood pressure control rates among patients with hypertension were largely stable. PINNACLE data also fueled a variety of quality measurement programs and 51 peer-reviewed publications.

8.
J Am Chem Soc ; 142(6): 2956-2967, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31902206

RESUMO

All-inorganic lead halide perovskite nanocrystals (NCs) are potential candidates for fabricating high-performance light-emitting diodes (LEDs) owing to their precisely tunable bandgaps, high photoluminescence (PL) efficiency, and excellent color purities. However, the performance of pure red (630-640 nm) all-inorganic perovskite LEDs is still limited by the halide segregation-induced instability of the electroluminescence (EL) of mixed halide CsPbI3-xBrx NCs. Herein, we report an effective approach to improving the EL stability of pure red all-inorganic CsPbI3-xBrx NC-based LEDs via the passivation of potassium bromide on NCs. By adding potassium oleate to the reaction system, we obtained potassium bromide surface-passivated (KBr-passivated) CsPbI3-xBrx NCs with pure red PL emission and a photoluminescence quantum yield (PLQY) exceeding 90%. We determine that most potassium ions present on the surface of NCs bind with bromide ions and thus demonstrate that potassium bromide surface passivation of NCs can both improve the PL stability and inhibit the halide segregation of NCs. Using KBr-passivated CsPbI3-xBrx NCs as an emitting layer, we fabricated stable and pure red perovskite LEDs with emission at 637 nm, showing a maximum brightness of 2671 cd m-2, maximum external quantum efficiency of 3.55%, and good EL stability. The proposed KBr-passivated NC strategy will open a new avenue for fabricating efficient, stable, and tunable pure color perovskite NC LEDs.

9.
Anim Biotechnol ; : 1-7, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31961257

RESUMO

The use of inorganic copper in feed is hazardous. As probiotics of animals, Candida utilis can absorb copper ions and transform them to organic copper. This study aimed to domesticate the ability of C. utilis (CICC 32211) to absorb and transform copper ions. So, C. utilis (CICC 32211) was cultured in media with different concentrations of copper ions for 24, 48 and 72 h to identify the optimum copper ion concentration. C. utilis (CICC 32211) strains were domesticated for three generations, then the absorption and distribution of copper ions in the yeast cells were studied. We found that the optimum concentration of copper ions was 110 µg/mL. After 48 h, the number of yeast cells was low, but copper ion absorption efficiency was maximized (43.83%). Most of the enriched copper ions were distributed in the yeast cell wall (up to 30.58% when grown in the medium with 110 µg/mL copper ions), while the intracellular copper ion content was low (2.095%). High concentrations of copper ions affected the morphological structure, element content and distribution of yeast cells.

10.
J Am Chem Soc ; 142(2): 690-695, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31895984

RESUMO

We report here the design of two multifunctional metal-organic frameworks (MOFs), mPT-Cu/Co and mPT-Cu/Re, comprising cuprous photosensitizers (Cu-PSs) and molecular Co or Re catalysts for photocatalytic hydrogen evolution (HER) and CO2 reduction (CO2RR), respectively. Hierarchical organization of Cu-PSs and Co/Re catalysts in these MOFs facilitates multielectron transfer to drive HER and CO2RR under visible light with an HER turnover number (TON) of 18 700 for mPT-Cu/Co and a CO2RR TON of 1328 for mPT-Cu/Re, which represent a 95-fold enhancement over their homogeneous controls. Photophysical and electrochemical investigations revealed the reductive quenching pathway in HER and CO2RR catalytic cycles and attributed the significantly improved performances of MOFs over their homogeneous counterparts to enhanced electron transfer due to close proximity between Cu-PSs and active catalysts and stabilization of Cu-PSs and molecular catalysts by the MOF framework.

11.
Bull Environ Contam Toxicol ; 104(2): 157-165, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31898750

RESUMO

The amendment of biochar in soils contaminated with persistent organic pollutants (POPs) is an environmentally friendly in situ remediation measure. Numerous studies focused on the application of biochars to reduce the uptake of POPs by plants in soils. In this review, we summarized the role of biochar in reducing the migration of POPs in soil-plant systems. The mechanisms of biochar reducing the bioavailability of POPs in the soil, i.e. immobilization and promoted biodegradation, and the influencing factors are fully discussed. Especially in rhizosphere amended with biochar, the synergistic effect of POPs-root exudates-microorganisms on the reduced bioavailability of POPs is analyzed. This paper suggests that future researches should focus on the long-term environmental fate of POPs sorbed on high-temperature biochars and the long-term impacts of low-temperature biochars on the interaction of POPs-root exudates-rhizosphere microorganisms. All the above are necessary for efficient and safe use of biochar for remediating POP-contaminated farmland soils.

12.
Med Biol Eng Comput ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900816

RESUMO

Irreversible osteoporosis may occur in astronauts during long-term space flight. The flow field of tissue fluid in the lacunar-canalicular system (LCS) of osteon and the mechanical response of osteocytes to the flow field under different gravity fields were studied by numerical simulation. This study is expected to explain how the decrease in liquid transmission within microgravity can be a cause of osteoporosis in astronauts from the perspective of biomechanics using a fundamental research approach. A 3D axisymmetric fluid-solid coupling finite element model of an osteon with a two-stage pore structure (Haversian canals and lacunar-canalicular network) and osteocytes was established. The model compared the influence of differences in pulsating pressure of arterioles in Haversian canal, from 33 mmHg to 45 mmHg within a microgravity field (0 g), Earth's gravity field (1 g), and a high G gravitational fields (2-8 g). The liquid flow velocity in the LCS within a microgravity field was less than that within a normal gravitational field, and the flow velocity increased with gravitational acceleration. There was a significant liquid pressure gradient in the osteocytes within a normal and higher gravitational field compared with in microgravity. A reduction in the fluid flow velocity and fluid shear stress on osteocytes in different zones in microgravity compared with Earth's gravitational field. For these reasons, possibly causing a decrease in mechanical conduction and biochemical function, even cell death, leads to increased osteoclast activity, eventually causing the loss of a large quantity of bone. Graphical abstract A 3D axisymmetric fluid-solid coupling finite element model of an osteon with a two-stage pore structure was established. The model compared the influence of magnitudes of gravity on liquid transmission in LCS and mechanical response of osteocytes. The mean flow velocity of liquid in various layers (shallow, middle, and deep) increased linearly as acceleration due to gravity increased, and there was a significant liquid pressure gradient in osteocytes within a normal gravitational field compared with in microgravity. In microgravity environment, the osteocytes were unable to experience the pressure difference compared to that of Earth, possibly causing a decrease in mechanical conduction and biochemical function, even cell death, leading to increased osteoclast activity, eventually causing the loss of a large quantity of bone.

13.
J Magn Reson Imaging ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31922327

RESUMO

BACKGROUND: The accurate preoperative differentiation between borderline and malignant epithelial ovarian tumors (BEOTs vs. MEOTs) is crucial for determining the proper surgical strategy and improving the patient's postoperative quality of life. Several diffusion and perfusion MRI technologies are valuable for the differentiation; however, which is the best remains unclear. PURPOSE: To compare the whole solid-tumor volume histogram analysis of diffusion-weighted imaging (DWI), diffusion kurtosis imaging (DKI), intravoxel incoherent motion (IVIM), and dynamic contrast-enhanced MRI (DCE-MRI) in the differentiation of BEOTs vs. MEOTs and to identify the correlations between the perfusion parameters from IVIM and DCE-MRI. STUDY TYPE: Retrospective. POPULATION: Twenty patients with BEOTs and 42 patients with MEOTs. FIELD STRENGTH/SEQUENCE: 1.5T/DWI, DKI, and IVIM models fitting from 13 different b factors and 40 phases DCE-MRI. ASSESSMENT: Histogram metrics were derived from the apparent diffusion coefficient (ADC), diffusion kurtosis (K), diffusion coefficient (Dk), pure diffusion coefficient (D), pseudodiffusion coefficient (D*), perfusion fraction (f), volume transfer constant (Ktrans ), rate constant (kep ), and extravascular extracellular volume fraction (ve ). STATISTICAL TESTS: The Mann-Whitney U-test and receiver operating characteristic curve were used to determine the best histogram metrics and parameters. Multivariate logistic regression analysis was used to determine the best combined model for each two from the four technologies. Spearman's rank correlation was used to analyze the correlations between the IVIM and DCE-MRI parameters. RESULTS: ADC, D, Dk, and D* were significantly higher in BEOTs than in MEOTs (P < 0.05). K, Ktrans , kep , and ve were significantly lower in BEOTs than in MEOTs (P < 0.05). The 10th percentile of Dk was the most reliable single metric, with an area under the curve (AUC) of 0.921. Dk combined with Ktrans yielded the highest AUC of 0.950. A weak inverse correlation was found between D and Ktrans (r = -0.320, P = 0.025) and between D and kep (r = -0.267, P = 0.037). DATA CONCLUSION: The 10th percentile of Dk was the most valuable metric and Dk combined with Ktrans had the best performance for differentiating BEOTs from MEOTs. There was no evident link between perfusion-related parameters derived from IVIM and DCE-MRI. LEVEL OF EVIDENCE: 4 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020.

14.
Biomaterials ; 234: 119743, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31962231

RESUMO

Cells live in a complex and dynamic microenvironment, and a variety of microenvironmental cues can regulate cell behavior. In addition to biochemical signals, biophysical cues can induce not only immediate intracellular responses, but also long-term effects on phenotypic changes such as stem cell differentiation, immune cell activation and somatic cell reprogramming. Cells respond to mechanical stimuli via an outside-in and inside-out feedback loop, and the cell nucleus plays an important role in this process. The mechanical properties of the nucleus can directly or indirectly modulate mechanotransduction, and the physical coupling of the cell nucleus with the cytoskeleton can affect chromatin structure and regulate the epigenetic state, gene expression and cell function. In this review, we will highlight the recent progress in nuclear biomechanics and mechanobiology in the context of cell engineering, tissue remodeling and disease development.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31968580

RESUMO

The study designs a comprehensive evaluation system for the prevention and control of occupational hazards, calculates its weight coefficient, and provides a potential strategic and effective tool for the scientific evaluation of occupational hazards in the iron and steel enterprises. The system was established through induction and analysis of relevant literature, personal interview, theoretical analysis, Delphi expert consultation, and special group discussions. Using an improved analytical hierarchy process fuzzy comprehensive evaluation model and on the basis of the improved Delphi expert investigation, the weight of the operability comprehensive evaluation index system is constructed. A three-level index system is established on the basis of harmful factors of occupational activities, health status of employees, protection facilities of occupational hazards, occupational health management, and so on. The index system structure is 4-20-95, and the weight coefficients of the four dimensions are 0.2516, 0.2428, 0.2550, and 0.2506. The recovery rate of the questionnaire was 82.5%, 100.0%, and 100.0%. The effective rates were 75.0%, 100.0%, and 100.0%. Conversely, the expert authority coefficients of the four dimensions are 0.875, 0.769, 0.832 and 0.800. Results show that the consistency factors of the four dimensions are statistically significant. Cronbach's α coefficient, standardized Cronbach's α coefficient, and split-half reliability of the comprehensive evaluation index system are 0.959, 0.950, and 0.810, respectively. After factor analysis, four common factors were extracted on the basis of expert opinions, and the cumulative variance was 63.1%. The comprehensive evaluation system for the prevention and control of occupational hazards in the iron and steel enterprises proposed by the study is relatively complete and reasonable.

17.
Eur J Radiol ; 124: 108822, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31951895

RESUMO

PURPOSE: To propose an automatic approach based on a convolutional neural network (CNN) to evaluate the quality of T2-weighted liver magnetic resonance (MR) images as nondiagnostic (ND) or diagnostic (D). MATERIALS AND METHODS: We included 150 T2-weighted liver MR imaging examinations in this retrospective study. Each slice of liver image was annotated with a label D or ND by two radiologists with seven and six years of experience, respectively. Additionally, the radiologists segmented the liver region manually as the ground truth for liver segmentation. A CNN was trained to segment the liver region and another CNN was used to classify the qualities of patches extracted from the liver region. The quality of an image was obtained from the percentage of nondiagnostic patches in all liver patches in the image. Treating nondiagnostic as positive, the accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), area under the receiver operating characteristic curve (AUC), and confusion matrix were used to evaluate our model. A Mann-Whitney U test was performed with the statistical significance set at 0.05. RESULTS: Our model achieved good performance with an accuracy of 88.3 %, sensitivity of 86.0 %, specificity of 89.4 %, PPV of 78.6 %, NPV of 93.4 %, and AUC of 0.911 (95 % confidence interval: 0.882-0.939, p < 0.05). The confusion matrix of our model indicated good concordance with that of the radiologists. CONCLUSIONS: The proposed two-step patch-based model achieved excellent performance when assessing the quality of liver MR images.

18.
Biomed Res Int ; 2020: 4087928, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31998789

RESUMO

Objective: Nonalcoholic fatty liver disease (NAFLD) is among the most common chronic liver diseases. However, the pathogenesis of NAFLD is not still unclear. This study aims at evaluating the role of zinc finger and BTB domain-containing 7A (ZBTB7A) in NAFLD. Methods: Western blotting, real-time reverse transcription PCR (RT-PCR), and immunohistochemistry were submitted to evaluate the level of ZBTB7A in the high fatty diet- (HFD-) induced NAFLD mouse model. In vitro, the expression of ZBTB7A was assessed in oleic acid- (OA-) induced HepG2 cells with western blotting and RT-PCR. The luciferase reporter assay was used to estimate the effect of ZBTB7A on the SREBP1 and NF-κB, and the ChIP assay was subjected to evaluate the direct binding to the SREBP1 promoter. Oil Red staining was used to detect lipid accumulation, and the ELISA was used to verify the levels of TG, T-CHO, and MDA. ZBTB7A was knocked down with siRNA, and RT-PCR was performed to analyze the lipogenesis-, fatty acid transporter-, and oxidation metabolism-related genes expression. The levels of ZBTB7A in primary hepatocyte, Kupffer, and hepatic stellate cells (HSCs) were tested by RT-PCR. Results: The upregulation of ZBTB7A expression was assessed in NAFLD mice, and ZBTB7A expression was positively correlated with TNFα, IL-6, TG, T-CHO, and MDA. ZBTB7A was highly expressed in the hepatocytes. In vitro, OA-induced ZBTB7A expression and ZBTB7A expression were closely associated with SREBP1c. ZBTB7A could activate the promoter activity of SREBP1 and activate NF-κB activity. Interestingly, the direct binding of ZBTB7A in the SREBP1 promoter was acquired in HepG2 cells. Inhibition of ZBTB7A expression could attenuate OA-induced lipid accumulation, inhibit the expression of the lipogenesis-related genes and fatty acid transporter genes, and promote the expression of oxidation metabolism-related genes. Conclusion: ZBTB7A plays a significant role in the development process of NAFLD, and obesity-induced upregulation of ZBTB7A promotes lipid accumulation through activation of SREBP1 and NF-κB. ZBTB7A may be a potential novel target for the therapy of NAFLD.

19.
Environ Pollut ; 257: 113570, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31767234

RESUMO

Microplastics with extremely high abundances are universally detected in marine and terrestrial systems. Microplastic pollution in the aquatic environment, especially in ocean, has become a hot topic and raised global attention. However, microplastics in soils has been largely overlooked. In this paper, the analytical methods, occurrence, transport, and potential ecological risks of microplastics in soil environments have been reviewed. Although several analytical methods have been established, a universal, efficient, faster, and low-cost analytical method is still not available. The absence of a suitable analytical method is one of the biggest obstacles to study microplastics in soils. Current data on abundance and distribution of microplastics in soils are still limited, and results obtained from different studies differ significantly. Once entering into surface soil, microplastics can migrate to deep soil through different processes, e.g. leaching, bioturbation, and farming activities. Presence of microplastics with high abundance in soils can alter fundamental properties of soils. But current conclusions on microplastics on soil organisms are still conflicting. Overall, research on microplastics pollution in soils is still in its infancy and there are gaps in the knowledge of microplastics pollution in soil environments. Many questions such as pollution level, ecological risks, transport behaviors and the control mechanisms are still unclear, which needs further systematical study.

20.
Environ Pollut ; 257: 113587, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31801669

RESUMO

Polychlorinated biphenyls (PCBs) are notorious environmental pollutants. For their hydrophobic and lipophilic capability, they are wildly spread to environment to threat human health thus attracts more attention. In this study, we observed increasing numbers of CD163 positive (CD163+) macrophages in aortic valve of ApoE-/- mice after 2,3,5-trichloro-6-phenyl-[1,4]-benzoquinone (PCB29-pQ) treatment, the metabolite of polychlorinated biphenyl. In addition, in vitro studies identified that PCB29-pQ exposure significantly provoked the shifting of RAW264.7 macrophages and bone marrow derived monocytes (BMDMs) to CD163+ macrophages. Upon PCB29-pQ administration, CD163 and CD206 levels were enhanced in RAW264.7 cells as well as in BMDMs. However, the concentration of iron and total cholesterol (TC) were reduced due to the boosting of ferroportin (Fpn) and ATP binding cassette transporter, subfamily A, member 1 (ABCA1) which are efflux transporters of iron and cholesterol individually. Further investigation on mechanism indicated that PCB29-pQ exposure induced reactive oxygen species (ROS), which may result in activation of nuclear factor erythroid 2-related factor 2 (Nrf2), a protein responsible for macrophage polarization. After that, we blocked Nrf2 through Nrf2 shRNA and ROS scavenger NAC, which significantly reversed the shifting of macrophage to CD163+ sub-population. These results confirmed the importance of Nrf2 in inducing macrophage polarization. In short, our study uncovered that PCB29-pQ could promote macrophage/monocyte polarization to CD163+ macrophage which would be a potential incentive to accelerate atherosclerosis through Nrf2 signaling pathway.

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