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1.
J Hazard Mater ; 421: 126721, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34358976

RESUMO

It is of great significance to develop a new gravity-driven filter to remove water pollutants, but it is still challenging. Here, a novel and simple strategy is demonstrated to manufacture fly ash (FA) ceramic foams showing a three-dimensional interconnected porous structure, with multiwalled carbon nanotubes (MWCNTs) implanted by combining carbamate grafting and polydimethylsiloxane coating. The polydimethylsiloxane formed a physical coating on the carbamate group, generating an effective thermal insulating layer on the outer side of the entire MWCNT. The FA foam, which shows a sufficient adsorption capacity for Pb(II) (51.67 ± 1.17 mg g-1) and Cd(II) (30.12 ± 0.37 mg g-1) at pH = 5, T = 25 °C, has a 96.33%, 95.12%, 89.50% removal efficiency for Cd(II), Pb(II), and particulate pollutants, and exhibits excellent recycling performance. This paper provides new opportunities to fabricate gravity-driven filters with low energy consumption for wastewater treatment.

2.
Environ Pollut ; 292(Pt A): 118306, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34634401

RESUMO

Slaughter wastewater is an important and wide range of environmental issues, and even threaten human health through meat production. A high efficiency and stability microsphere-immobilized Bacillus velezensis strain was designed to remove organic matter and inhibit the growth of harmful bacteria in process of slaughter wastewater. Bacillus velezensis was immobilized on the surface of sodium alginate (SA)/Polyvinyl alcohol (PVA)/Nano Zinc Oxide (Nano-ZnO) microsphere with the adhesion to bio-carrier through direct physical adsorption. Results indicated that SA/PVA/ZnO and SA/ZnO microspheres could inhibit E.coli growth with adding 0.15 g/L nano-ZnO and not affect Bacillus velezensis strain, and the removal the chemical oxygen demand (COD) rates of SA/PVA/ZnO microsphere immobilized cells are 16.99%, followed by SA/ZnO (13.69%) and free bacteria (7.61%) from 50% concentration slaughter wastewater within 24 h at 37 °C, pH 7.0, and 120 rpm, a significant difference was found between the microsphere and control group. Moreover, when the processing time reaches 36 h, COD degradation of SA/PVA/ZnO microsphere is obviously higher than other groups (SA/PVA/ZnO:SA/ZnO:control vs 18.535 : 15.446: 10.812). Similar results were obtained from 30% concentration slaughter wastewater. Moreover, protein degradation assay was detected, and there are no significant difference (SA/PVA/ZnO:SA/ZnO:control vs 35.4 : 34.4: 36.0). The design of this strategy could greatly enhance the degradation efficiency, inhibit the growth of other bacteria and no effect on the activity of protease in slaughter wastewater. These findings suggested that the nano-ZnO hydrogel immobilization Bacillus velezensis system wastewater treatment is a valuable alternative method for the remediation of pollutants from slaughter wastewater with a novel and eco-friendly with low-cost investment as an advantage.

3.
Front Plant Sci ; 12: 760599, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721489

RESUMO

Both plant communities and soil microbes have been reported to be correlated with ecosystem multifunctionality (EMF) in terrestrial ecosystems. However, the process and mechanism of aboveground and belowground communities on different EMF patterns are not clear. In order to explore different response patterns and mechanisms of EMF, we divided EMF into low (<0) and high patterns (>0). We found that there were contrasting patterns of low and high EMF in the alpine grassland ecosystem on the Tibetan Plateau. Specifically, compared with low EMF, environmental factors showed higher sensitivity to high EMF. Soil properties are critical factors that mediate the impact of community functions on low EMF based on the change of partial correlation coefficients from 0 to 0.24. In addition, plant community functions and microbial biomass may mediate the shift of EMF from low to high patterns through the driving role of climate across the alpine grassland ecosystem. Our findings will be vital to clarify the mechanism for the stability properties of grassland communities and ecosystems under ongoing and future climate change.

4.
J Org Chem ; 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34726921

RESUMO

Improving both the activity and selectivity of the C-H borylation reaction is currently a hot research topic but also a challenge. In this regard, we suggest a multistrategy combining directing group, coordination unsaturated metal center, and cationic character. Based on Reek's catalyst, we designed a new unsaturated cationic catalyst (1) featuring a directing group for C-H borylation. The calculated free energy barrier of C-H activation is only 7.2 kcal/mol, indicating that the cationic catalyst has higher activity than the original neutral catalyst in this process. Moreover, the comparison suggests that the ortho-C-H borylation pathway is more favorable than the meta and para pathways. The catalyst deconstructions are further performed and prove that the ortho-selectivity is attributed to hydrogen-bonding interactions between the directing group and the substrate, although the ortho site is sterically and electronically unfavorable.

5.
Anim Biosci ; 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34727633

RESUMO

Objective: Excessive lipid accumulation in adipocytes results in prevalence of obesity and metabolic syndrome. Curcumin (CUR), a naturally phenolic active ingredient, has been shown to have lipid-lowering effects. However, its underlying mechanisms have remained largely unknown. Therefore, the study aims to determine the effect of CUR on cellular lipid accumulation in porcine subcutaneous preadipocytes (PSPA) and to clarify novel mechanisms. Methods: PSPA were cultured and treated with or without CUR. Both Cell Counting Kit-8 and lactate dehydrogenase release assays were used to examine cytotoxicity. Intracellular lipid contents were measured by Oil-Red-O staining extraction and TG quantification. Apoptosis was determined by flow cytometry and TUNEL staining. Adipogenic and apoptosis genes were analyzed by qPCR and Western blot. Results: CUR dose-dependently reduced the proliferation and lipid accumulation of PSPA. Noncytotoxic doses of CUR (10-20 µM) significantly inhibited extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and expression of adipogenic genes peroxisome proliferation-activity receptor-γ (PPAR-γ), CCAAT/enhancer binding protein-α, sterol regulatory element-binding protein-1c, adipocyte protein-2, glucose transporter-4 as well as key lipogenic enzymes fatty acid synthase and acetyl-CoA carboxylase, while ERK1/2 activation significantly reversed CUR-reduced lipid accumulation by increasing PPAR-γ. Furthermore, compared with differentiation induced media treated cells, higher dose of CUR (30 µM) significantly decreased the expression of AKT and B-cell lymphoma-2 (BCL-2), while increased the expression of BCL-2-associated X (BAX) and the BAX/BCL-2 expression ratio, suggesting triggered apoptosis by inactivating AKT and increasing BAX/BCL-2 ratio and Caspase-3 expression. Moreover, AKT activation significantly rescued CUR inhibiting lipid accumulation via repressing apoptosis. Conclusion: These results demonstrate that CUR is capable of suppressing differentiation by inhibiting ERK1/2-PPAR-γ signaling pathway and triggering apoptosis via decreasing AKT and subsequently increasing BAX/BCL-2 ratio and Caspase-3, suggesting that CUR provides an important method for the reduction of porcine body fat, as well as the prevention and treatment of human obesity.

6.
Cell Death Dis ; 12(11): 1045, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732698

RESUMO

Rapid adaptation to a hypoxic environment is an unanswered question that we are committed to exploring. At present, there is no suitable strategy to achieve rapid hypoxic adaptation. Here, we demonstrate that fasting preconditioning for 72 h reduces tissue injuries and maintains cardiac function, consequently significantly improving the survival rates of rats under extreme hypoxia, and this strategy can be used for rapid hypoxic adaptation. Mechanistically, fasting reduces blood glucose and further suppresses tissue mTOR activity. On the one hand, fasting-induced mTOR inhibition reduces unnecessary ATP consumption and increases ATP reserves under acute hypoxia as a result of decreased protein synthesis and lipogenesis; on the other hand, fasting-induced mTOR inhibition improves mitochondrial oxygen utilization efficiency to ensure ATP production under acute hypoxia, which is due to the significant decrease in ROS generation induced by enhanced mitophagy. Our findings highlight the important role of mTOR in acute hypoxic adaptation, and targeted regulation of mTOR could be a new strategy to improve acute hypoxic tolerance in the body.

7.
Cell Death Dis ; 12(11): 1068, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34753919

RESUMO

Systemic transplantation of oxygen-glucose deprivation (OGD)-preconditioned primary microglia enhances neurological recovery in rodent stroke models, albeit the underlying mechanisms have not been sufficiently addressed. Herein, we analyzed whether or not extracellular vesicles (EVs) derived from such microglia are the biological mediators of these observations and which signaling pathways are involved in the process. Exposing bEnd.3 endothelial cells (ECs) and primary cortical neurons to OGD, the impact of EVs from OGD-preconditioned microglia on angiogenesis and neuronal apoptosis by the tube formation assay and TUNEL staining was assessed. Under these conditions, EV treatment stimulated both angiogenesis and tube formation in ECs and repressed neuronal cell injury. Characterizing microglia EVs by means of Western blot analysis and other techniques revealed these EVs to be rich in TGF-ß1. The latter turned out to be a key compound for the therapeutic potential of microglia EVs, affecting the Smad2/3 pathway in both ECs and neurons. EV infusion in stroke mice confirmed the aforementioned in vitro results, demonstrating an activation of the TGF-ß/Smad2/3 signaling pathway within the ischemic brain. Furthermore, enriched TGF-ß1 in EVs secreted from OGD-preconditioned microglia stimulated M2 polarization of residing microglia within the ischemic cerebral environment, which may contribute to a regulation of an early inflammatory response in postischemic hemispheres. These observations are not only interesting from the mechanistic point of view but have an immediate therapeutic implication as well, since stroke mice treated with such EVs displayed a better functional recovery in the behavioral test analyses. Hence, the present findings suggest a new way of action of EVs derived from OGD-preconditioned microglia by regulating the TGF-ß/Smad2/3 pathway in order to promote tissue regeneration and neurological recovery in stroke mice.

8.
Front Pediatr ; 9: 759535, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778149

RESUMO

Objective: The aim of this study was to investigate possible associations between Heparin-binding protein (HBP) and the development of respiratory failure (RF) and sepsis in critically ill children with severe community-acquired pneumonia (CAP). Methods: This study enrolled 157 children with severe CAP admitted to Intensive Care Unit (ICU). At ICU admission, the levels of HBP and other biomarkers, including C-reactive protein, interleukin-6 (IL-6), procalcitonin, white blood cells, neutrophil percentage, and D-dimer, were determined. Results: Of the enrolled patients, 106 developed RF (35 with RF at enrollment and 71 with RF after enrollment), while 51 did not developed RF. The number of patients progressing to sepsis in those with or without RF were 34 (21 with severe sepsis) and 14, respectively. The plasma level of HBP at admission was more than eightfold higher than the upper normal value. HBP, IL-6, and D-dimer could significantly predict the development of RF, and a high level of HBP (odds ratio = 1.008, 95% confidence interval: 1.003-1.013) was independently associated with the development of RF in this population. Compared with other biomarkers, HBP was the best indicator of progression to severe sepsis, with an area under the receiver operating characteristic curve of 0.85, the best specificity at 96.30%, and a positive predictive value of 92.86% at the optimal cut-off value of 340.29 ng/mL. The HBP level was also positively correlated with other conventional biomarkers. Conclusion: HBP might represent a better predictor of disease progression in children with severe CAP than currently used biomarkers.

9.
Genet Epidemiol ; 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34787916

RESUMO

Although genome-wide association studies (GWAS) often collect data on multiple correlated traits for complex diseases, conventional gene-based analysis is usually univariate, and therefore, treating traits as uncorrelated. Multivariate analysis of multiple correlated traits can potentially increase the power to detect genes that affect some or all of these traits. In this study, we propose the multivariate hierarchically structured variable selection (HSVS-M) model, a flexible Bayesian model that tests the association of a gene with multiple correlated traits. With only summary statistics, HSVS-M can account for the correlations among genetic variants and among traits simultaneously and can also estimate the various directions and magnitudes of associations between a gene and multiple traits. Simulation studies show that HSVS-M substantially outperforms competing methods in various scenarios, particularly when variants in a gene are associated with a trait in similar directions and magnitudes. We applied HSVS-M to the summary statistics of a meta-analysis GWAS on four lipid traits from the Global Lipids Genetics Consortium and identified 15 genes that have also been confirmed as risk factors in previous studies.

10.
Appl Opt ; 60(31): 9672-9680, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807150

RESUMO

For reshaping aperture size and correcting low-order aberration of laser beams with large aspect ratios, a simplified analytical method is proposed to design an anamorphic refractive shaping system, which is composed of double-plane symmetric lenses. The simplified method enables performing a global study of aberrations via calculating the analytical primary wave aberration function under paraxial approximation. The aberration balance is analyzed with a three-lens laser collimating system and a compact four-lens laser expanding system. Lens bending and conic surfaces are introduced to decrease ray errors. Through the simplified analytical method, anamorphic refractive shaping systems for laser beams with large aspect ratios can be adequately analyzed and conveniently designed.

11.
Appl Opt ; 60(31): 10002-10008, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807195

RESUMO

Large-scale optical fiber phased arrays (OFPAs) are capable of realizing high-power lasers and high-speed beam steering, which are widely used in long-distance detection and communication. However, dephasing occurring from optical fiber jitter and power amplifier noise can reduce beam quality and steering precision in applications. We demonstrate a two-dimensional 64-element OFPA system that employs a stochastic parallel gradient descent algorithm to synchronize the phases and thus achieve high-quality multi-beam output. Using multi-beam steering, the total scan time for covering a certain field of view can be shorter compared to single-beam steering. Moreover, an avalanche photodiode array is used to enhance the precision of the voltage for beam steering. Experimental results show that the peak sidelobe ratio of the main beam achieves 23.7 dB, and the speed of the beam steering between two discretionary angles is 128 kHz.

13.
Daru ; 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34817844

RESUMO

Glucocorticoids are used as a first-line treatment for severe alcoholic hepatitis, and albumin reduces both the number of hospitalizations and mortality in patients with decompensated cirrhosis. However, for acute-on-chronic liver failure (ACLF), there is no definitive evidence that glucocorticoid therapy is beneficial. In this case report, we describe a male patient who developed into ACLF based on alcoholic cirrhosis, whose symptoms and clinical indicators continued to deteriorate after initial symptomatic treatment. The patient's condition gradually improved after low-dose glucocorticoid therapy, and long-term albumin supplementation resulted in a satisfactory outcome.

14.
Opt Express ; 29(23): 37399-37417, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34808812

RESUMO

Propagation-based X-ray phase-contrast computed tomography (PB-PCCT) has been increasingly popular for distinguishing low contrast tissues. Phase retrieval is an important step to quantitatively obtain the phase information before the tomographic reconstructions, while typical phase retrieval methods in PB-PCCT, such as homogenous transport of intensity equation (TIE-Hom), are essentially low-pass filters and thus improve the signal to noise ratio at the expense of the reduced spatial resolution of the reconstructed image. To improve the reconstructed spatial resolution, measured phase contrast projections with high edge enhancement and the phase projections retrieved by TIE-Hom were weighted summed and fed into an iterative tomographic algorithm within the framework of the adaptive steepest descent projections onto convex sets (ASD-POCS), which was employed for suppressing the image noise in low dose reconstructions because of the sparse-view scanning strategy or low exposure time for single phase contrast projection. The merging strategy decreases the accuracy of the linear model of PB-PCCT and would finally lead to the reconstruction failure in iterative reconstructions. Therefore, the additive median root prior is also introduced in the algorithm to partly increase the model accuracy. The reconstructed spatial resolution and noise performance can be flexibly balanced by a pair of antagonistic hyper-parameters. Validations were performed by the established phase-contrast Feldkamp-Davis-Kress, phase-retrieved Feldkamp-Davis-Kress, conventional ASD-POCS and the proposed enhanced ASD-POCS with a numerical phantom dataset and experimental biomaterial dataset. Simulation results show that the proposed algorithm outperforms the conventional ASD-POCS in spatial evaluation assessments such as root mean square error (a ratio of 9.78%), contrast to noise ratio (CNR) (a ratio of 7.46%), and also frequency evaluation assessments such as modulation transfer function (a ratio of 66.48% of MTF50% (50% MTF value)), noise power spectrum (a ratio of 35.25% of f50% (50% value of the Nyquist frequency)) and noise equivalent quanta (1-2 orders of magnitude at high frequencies). Experimental results again confirm the superiority of proposed strategy relative to the conventional one in terms of edge sharpness and CNR (an average increase of 67.35%).

15.
Opt Express ; 29(23): 37580-37590, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34808827

RESUMO

In this paper, we propose a chaos-based visible light communication system, wherein multiple users can access the network via the multi-carrier code division multi-access (MC-CDMA). By utilizing the high security property of chaotic sequences being aperiodic and sensitive to initial values, secure access can be achieved. However, the multi-carrier transmission suffers from high peak to average power ratio (PAPR) due to the superposition of multiple carriers, which reduces the lifetime of the light-emitting diodes (LEDs). In order to suppress the PAPR, we propose a joint matrix transform and dual layered phase sequencing (MT-DLPS) scheme. By reducing the autocorrelations of signals, the PAPR can be reduced. Moreover, the computation complexity is analyzed. Simulations are then conducted to validate that the PAPR is effectively reduced while maintaining satisfactory bit error rate (BER) performances.

16.
Gastroenterol Rep (Oxf) ; 9(5): 443-450, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34733530

RESUMO

Background: The clinical value of programmed death-ligand 1 (PD-L1) expression in colorectal liver oligometastases (CLOs) remains undefined. This study aimed to detect PD-L1 in the microenvironment of CLOs and determine its association with patient prognosis. Methods: We collected 126 liver-resection specimens from CLO patients who underwent curative liver resection between June 1999 and December 2016. Immunohistochemistry (IHC) was performed to assess PD-L1 expression in paraffin-embedded specimens. Overall survival (OS) and recurrence-free survival (RFS) were analysed using the Kaplan-Meier method and log-rank test. Results: PD-L1 was mainly expressed in the stroma of liver oligometastases. Patients with high PD-L1 expression had a higher proportion of clinical-risk scores (CRSs) of 2-4 (67.7% vs 40.4%; P = 0.004). With a median 58-month follow-up, patients with high PD-L1 expression had a significantly lower 3-year OS rate (65.5% vs 92.7%; P = 0.001) and 3-year RFS rate (34.7% vs 83.8%; P < 0.001) than patients with low PD-L1 expression. Multivariate Cox analysis demonstrated that high PD-L1 expression (hazard ratio [HR] = 3.581; 95% confidence interval [CI] 2.301-9.972; P = 0.015), CRS 2-4 (HR = 6.960; 95% CI 1.135-42.689; P = 0.036) and increased preoperative CA19-9 (HR = 2.843; 95% CI 1.229-6.576; P = 0.015) were independent risk factors for OS. High PD-L1 expression (HR = 4.815; 95% CI 2.139-10.837; P < 0.001) and lymph-node metastasis (HR = 2.115; 95% CI 1.041-4.297; P = 0.038) were independent risk factors for RFS. Conclusion: This study found that PD-L1 was commonly expressed in the tumour stroma of CLOs and high PD-L1 expression was associated with poor prognosis.

17.
Stat Med ; 2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34747059

RESUMO

Multi-parametric magnetic resonance imaging (mpMRI) has been playing an increasingly important role in the detection of prostate cancer (PCa). Various computer-aided detection algorithms were proposed for automated PCa detection by combining information in multiple mpMRI parameters. However, there are specific features of mpMRI, including between-voxel correlation within each prostate and heterogeneity across patients, that have not been fully explored but could potentially improve PCa detection if leveraged appropriately. This article proposes novel Bayesian approaches for voxel-wise PCa classification that accounts for spatial correlation and between-patient heterogeneity in the mpMRI data. Modeling the spatial correlation is challenging due to the extreme high dimensionality of the data, and we propose three scalable approaches based on Nearest Neighbor Gaussian Process (NNGP), reduced-rank approximation, and a conditional autoregressive (CAR) model that approximates a Gaussian Process with the Matérn covariance, respectively. Our simulation study shows that properly modeling the spatial correlation and between-patient heterogeneity can substantially improve PCa classification. Application to in vivo data illustrates that classification is improved by all three spatial modeling approaches considered, while modeling the between-patient heterogeneity does not further improve our classifiers. Among the proposed models, the NNGP-based model is recommended given its high classification accuracy and computational efficiency.

20.
Bioengineered ; 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34802381

RESUMO

Gastric cancer (GC) is among the most frequent malignancies originating from the digestive system worldwide, while the role and specific mechanism of integrin subunit alpha 11 (ITGA11) in GC remain unclear. This study probes the expression characteristics and function of ITGA11 in GC. Firstly, The ITGA11 profile in GC tissues and paracancerous non-tumor tissues was assessed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot (WB), and the association between ITGA11 and GC patients' clinicopathological indicators was evaluated. ITGA11 knockdown models were set up in GC cell lines MKN45 and AGS. Cell proliferation was determined by the cell counting kit-8 (CCK-8) assay and colony formation assay. WB was utilized to gauge the expression of apoptosis-related proteins (Bax, Bcl2, Bad, and C-Caspase3) and the PI3K/AKT pathway. We discovered that the ITGA11 expression was boosted in GC tissues and was related to the unfavorable prognosis of GC patients. Additionally, ITGA11 knockdown abated GC cell proliferation, invasion and migration, and enhanced cell apoptosis. In animal experiments, the tumorigenesis of GC cells knocking down ITGA11 was reduced. Mechanically, knocking down ITGA11 notably inactivated the PI3K/AKT axis. The tumor-suppressive effect mediated by ITGA11 knockdown was attenuated after activating the PI3K/AKT pathway with insulin like growth factor 1 (IGF-1). Overall, this study substantiated that the ITGA11 expression was heightened in GC tissues, which affected GC progression by modulating the PI3K/AKT pathway.

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