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1.
J Orthop Surg Res ; 15(1): 55, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32070392

RESUMO

BACKGROUND: Heel pain is one of the most common complaints in foot and ankle clinic, and one of the leading causes of heel pain is plantar fasciitis. METHODS: A retrospective analysis was carried out in 31 cases (39 feet) of patients with intractable plantar fasciitis. In the enrolled 26 cases, 16 patients (19 feet) received open plantar fascia release, and the other 15 patients (20 feet) received percutaneous radiofrequency ablation. The surgical results were assessed by visual analog scale (VAS) and American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale (AOFAS-AH) before and after surgery in all patients. RESULTS: All 31 patients were followed up successfully, with a mean follow-up time of 58.77 months. There were no differences of patient's demographics and characteristics information between the two groups. The average operative time of the feet in the open plantar fascia release is longer than that in the percutaneous radiofrequency ablation. Furthermore, the percutaneous radiofrequency ablation group had a shorter recovery time to normal activity than the open plantar fascia release group. There were no differences of postoperative VAS scores and the AOFAS-AH scores between the two groups. All patients reported satisfaction after either operation. CONCLUSION: The symptoms of pain and limb function were significantly improved in patients both of the partial plantar fascia release treated group and the percutaneous radiofrequency ablation treated group. The two types of surgical procedures shared the same long-term curative effects. However, percutaneous radiofrequency ablation was a better technique from the point of shorter operative time and postoperative recovery time. TRIAL REGISTRATION: Retrospectively registered.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32048077

RESUMO

Cochlear implant (CI) listeners typically perform poorly on tasks involving the pitch of complex tones. This limitation in performance is thought to be mainly due to the restricted number of active channels and the broad current spread that leads to channel interactions and subsequent loss of precise spectral information, with temporal information limited primarily to temporal-envelope cues. Little is known about the degree of spectral resolution required to perceive combinations of multiple pitches, or a single pitch in the presence of other interfering tones in the same spectral region. This study used noise-excited envelope vocoders that simulate the limited resolution of CIs to explore the perception of multiple pitches presented simultaneously. The results show that the resolution required for perceiving multiple complex pitches is comparable to that found in a previous study using single complex tones. Although relatively high performance can be achieved with 48 channels, performance remained near chance when even limited spectral spread (with filter slopes as steep as 144 dB/octave) was introduced to the simulations. Overall, these tight constraints suggest that current CI technology will not be able to convey the pitches of combinations of spectrally overlapping complex tones.

3.
BMC Musculoskelet Disord ; 21(1): 85, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32033561

RESUMO

BACKGROUND: Hip fractures have become a severe public health problem, especially in very elderly patients. Most of them are treated with low molecular weight heparin as prophylaxis or treatment of venous thromboembolism. Heparin-induced thrombocytopenia is one of the complications induced by low molecular weight heparin, which may cause poor prognosis. However, there is not enough awareness for heparin-induced thrombocytopenia in very elderly trauma patients. CASE PRESENTATION: We report a case of hip fracture with heparin-induced thrombocytopenia in a very elderly patient. The patient developed heparin-induced thrombocytopenia, digestive hemorrhage and acute colonic pseudo-obstruction after the use of low molecular weight heparin, which eventually led to death. CONCLUSIONS: This is the first case report of digestive hemorrhage and acute colonic pseudo-obstruction in heparin-induced thrombocytopenia patients with major trauma. This case highlights the severity of HIT in very elderly patients with hip fractures using low molecular weight heparin, and the need for platelet monitoring in these patients. We indicate that there may be a correlation of pathogenesis between digestive hemorrhage and acute colonic pseudo-obstruction in heparin-induced thrombocytopenia patients.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32054268

RESUMO

We designed and synthesized two non-fullerene acceptors (CDT-TFP and C8X-TFP), which comprise a central 4H-cyclopenta[2,1-b:3,4-b']dithiophene (CDT) as the bridge and two thiophene-fused perylene diimide (TFP) units. The bulky side chains, such as the 4-hexylphenyl side chains, on the CDT bridge can effectively prevent the acceptor molecules from forming large aggregates and the π-π stacking of the terminal planar TFP units can form effective electron transport pathways when blending with the donor polymers. These non-fullerene acceptors are used to fabricate organic solar cells (OSCs) by blending with regioregular middle bandgap polymer reg-PThE. The as-cast devices based on reg-PThE:CDT-TFP show the best PCE of 8.36% with a Voc of 1.10 V, Jsc of 12.43 mA cm-2 and FF of 61.4%; whereas, the analogue PDI dimers (CDT-PDI) that comprising two PDI units bridged with a CDT unit, show only a 2.59% PCE with a Voc of 0.92 V, Jsc of 6.82 mA cm-2 and FF of 41.5%. Our results have demonstrated that non-fullerene acceptors comprising planar PDI units can achieve excellent photovoltaic performance and provide meaningful guidelines for the design of PDI based non-fullerene electron acceptors for efficient OSCs.

5.
Phys Chem Chem Phys ; 22(7): 4205-4215, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32043099

RESUMO

Binary self-assembled monolayers (SAMs) combining a Y-shaped aromatic carboxylic acid (1,3,5-benzenetribenzoic acid, H3BTB) and a cage-type alicyclic carboxylic acid (adamantane carboxylic acid, AdCA) were investigated by scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. The SAMs, prepared by molecular adsorption from solution on Au substrates modified by underpotential deposition of Ag, exhibit a pronounced dependence of their structure on the assembly protocol. Exposing an H3BTB SAM to AdCA, the highly regular row structure of the native H3BTB layer persists and STM imaging does not show signs of AdCA adsorption. This is in striking contrast to the disordered arrangements of H3BTB and the presence of AdCA employing the inverted adsorption sequence or coadsorption of the two molecules. However, spectroscopic analysis of the H3BTB SAM exposed to AdCA reveals the presence also of the latter, suggesting that the AdCA molecules are hidden in the nanotunnels of the H3BTB monolayer. Direct evidence for the intercalation of AdCA is obtained by STM manipulation experiments which lay bare areas of AdCA molecules upon local removal of H3BTB. Surprisingly, these are densely packed and arranged into a highly ordered monolayer. Formation of such a compact AdCA layer is explained by expulsion of AdCA from the H3BTB nanotunnels of the surrounding intact mixed SAM, driven by release of stress in the nanotunnels built up when AdCA is intercalated.

6.
Ther Drug Monit ; 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32039940

RESUMO

BACKGROUND: The objective of this study was to investigate the serum concentrations of olanzapine in relation to age, sex, and other factors in Chinese patients aged between 10 and 90 years. METHODS: Data for 884 olanzapine patients, deposited between 2016 and 2017, were retrieved from the therapeutic drug monitoring (TDM) database of the Affiliated Brain Hospital of Guangzhou Medical University. The effects of covariates on serum olanzapine concentration, dose-normalized concentration (C/D ratio), and normalized concentration (C/D/weight) were investigated. RESULTS: Generally, males had lower olanzapine concentration, C/D ratio, and C/D/weight than females (p<0.001). Smoking and drinking reduced olanzapine concentration, C/D ratio, and C/D/weight (p<0.001). Co-administration with valproate decreased olanzapine concentration, C/D ratio, and C/D/weight by about 16%, 30% and 40%, respectively (p<0.001). Patients younger than 60 years had higher olanzapine concentrations (p<0.05), but lower C/D ratios and C/D/weight (p<0.001) than patients older than 60. Age was correlated with olanzapine concentration (r = -0.082, p<0.05), C/D ratio (r = 0.196, p<0.001), and C/D/weight (r = 0.169, p<0.001). Sample timing post-dose and diagnostic factors also contributed to the olanzapine concentrations. Multiple linear regression analysis revealed significant influences of dosage, age, sex, valproate comedication, smoking, post-dose interval, and schizophrenia (vs bipolar affective disorders) on serum olanzapine concentrations. CONCLUSIONS: The metabolism of olanzapine may be altered by several factors. Patients characterized with a combination of factors may benefit from TDM for the adjustment of olanzapine dose to minimize adverse reactions.

7.
Nat Cell Biol ; 22(2): 167-174, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32029896

RESUMO

Branched-chain amino acid (BCAA) metabolism is potentially linked with development of pancreatic ductal adenocarcinoma (PDAC)1-4. BCAA transaminase 2 (BCAT2) was essential for the collateral lethality conferred by deletion of malic enzymes in PDAC and the BCAA-BCAT metabolic pathway contributed to non-small-cell lung carcinomas (NSCLCs) other than PDAC3,4. However, the underlying mechanism remains undefined. Here we reveal that BCAT2 is elevated in mouse models and in human PDAC. Furthermore, pancreatic tissue-specific knockout of Bcat2 impedes progression of pancreatic intraepithelial neoplasia (PanIN) in LSL-KrasG12D/+; Pdx1-Cre (KC) mice. Functionally, BCAT2 enhances BCAA uptake to sustain BCAA catabolism and mitochondrial respiration. Notably, BCAA enhances growth of pancreatic ductal organoids from KC mice in a dose-dependent manner, whereas addition of branched-chain α-keto acid (BCKA) and nucleobases rescues growth of KC organoids that is suppressed by BCAT2 inhibitor. Moreover, KRAS stabilizes BCAT2, which is mediated by spleen tyrosine kinase (SYK) and E3 ligase tripartite-motif-containing protein 21 (TRIM21). In addition, BCAT2 inhibitor ameliorates PanIN formation in KC mice. Of note, a lower-BCAA diet also impedes PDAC development in mouse models of PDAC. Thus, BCAT2-mediated BCAA catabolism is critical for development of PDAC harbouring KRAS mutations. Targeting BCAT2 or lowering dietary BCAA may have translational significance.

8.
Int Immunol ; 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31930324

RESUMO

Intrahepatic cholestasis induced by drug toxicity may cause cholestatic hepatic injury (CHI) leading to liver fibrosis and cirrhosis. The G protein-coupled bile acid receptor 1 (TGR5) is a membrane receptor with well-known roles in the regulation of glucose metabolism and energy homeostasis. However, the role and mechanism of TGR5 in the context of inflammation during CHI remains unclear. Wild-type (WT) and TGR5 knockout (TGR5-/-) mice with CHI induced by bile duct ligation (BDL) were involved in vivo, and WT and TGR5-/- bone marrow-derived macrophages (BMDMs) were used in vitro. TGR5 deficiency significantly exacerbated BDL-induced liver injury, inflammatory responses, and hepatic fibrosis compared with WT mice in vivo. TGR5-/- macrophages were more susceptible to lipopolysaccharide (LPS) stimulation than WT macrophages. TGR5 activation by its ligand suppressed LPS-induced pro-inflammatory responses in WT but not TGR5-/- BMDMs. Notably, expression of ß-catenin was effectively inhibited by TGR5 deficiency. Furthermore, TGR5 directly interacted with Gsk3ß to repress the interaction between Gsk3ß and ß-catenin, thus disrupting the ß-catenin destruction complex. The pro-inflammatory nature of TGR5-knockout was almost abolished by lentivirus-mediated ß-catenin overexpression in BMDMs. BMDM migration in vitro was accelerated under TGR5-deficient conditions or supernatant from LPS-stimulated TGR5-/- BMDMs. From a therapeutic perspective, TGR5-/- BMDM administration aggravated BDL-induced CHI, which was effectively rescued by ß-catenin overexpression. Our findings reveal that TGR5 plays a crucial role as a novel regulator of immune-mediated CHI by destabilizing the ß-catenin destruction complex, with therapeutic implications for the management of human CHI.

9.
Oral Dis ; 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31926047

RESUMO

CD44, a cell-surface glycoprotein, functions as a receptor for hyaluronic acid. Our research group has previously shown that CD44 is a biomarker for the CD44hi cells (tumor-initiating cells; TICs) in murine salivary gland tumors. However, little is known concerning the biological roles of CD44 in the tumorigenesis of pleomorphic adenoma. The present study is aimed to investigate the effects of CD44 on the proliferation, invasive capability, and apoptosis of TICs in vitro, as well as the tumorigenicity of TICs in vivo. The results demonstrated that knockdown of CD44 attenuated the malignant phenotype of TICs. Furthermore, in vivo xenograft studies indicated that CD44 knockdown inhibited tumorigenesis of pleomorphic adenoma. In addition, neither the CD44low cells nor the CD44-modified CD44low cells developed neo-tumors, which indicated that overexpression of CD44 did not enable the CD44low cells to be transformed into TICs. Taken together, these data demonstrate that CD44 not only acts as a biomarker, but also functions as a key player in the tumor-initiating capacity of TICs. These results shed light on the pathogenesis of salivary gland tumors and provide a potential therapeutic target for treating pleomorphic adenoma.

10.
Sci Total Environ ; 709: 136171, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31905582

RESUMO

Biochar-mineral (bentonite/calcite) composite (BC-CM) prepared at different temperatures were tested under varied conditions for effective removal of lead (Pb) from aqueous solution. With increasing pyrolysis temperature, increased surface area, pore volume, bentonite decomposition and less or no decomposition of calcite occurred. Bentonite-biochar (BCS) and calcite-biochar (CCS) prepared at 700 °C were found most suitable for efficient removal of Pb (99.9%). Bentonite and calcite acted as catalyst and contributed to changes in yield, pH, texture, functional groups, minerals and carbonization that facilitated efficient Pb removal by BCS 700 and CCS 700. Pb concentration, pH, dose of BCS and CCS, and contact time were further optimized using response surface methodology (RSM) for maximizing removal percentage (R%) of Pb and adsorption capacity (qt). Both BCS 700 and CCS 700 showed similar effects (positive/negative) of factors on R% and qt. Under optimized conditions, 0.21 g of BCS 700 effectively removed 99.2% of 431 mg/L in 3.6 h at solution pH of 4.2, while 0.07 g CCS 700 removed 97.06% of 232 mg/L in 3.5 h at 5.5 pH. Removal of Pb onto both BCS and CCS was by monolayer adsorption with maximum adsorption capacity of 500 mg/g. Rapid Pb removal was observed within 2 h of contact time (CCS 700 > BCS 700) and equilibrium was achieved within 10 h. BCS 700 followed first order and CCS 700 followed second order kinetic model. Electrostatic attraction between Pb ions and mineral groups present in BCS 700 and CCS 700 also played important role in Pb removal. This study clearly demonstrated that composite of biochar with bentonite or calcite under optimized conditions significantly improved Pb removal and adsorption capacity that can be further utilized for larger scale applications.

11.
J Med Chem ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31990537

RESUMO

Endothelial lipase (EL) hydrolyzes phospholipids in high-density lipoprotein (HDL) resulting in reduction in plasma HDL levels. Studies with murine transgenic, KO, or loss-of-function variants strongly suggest that inhibition of EL will lead to sustained plasma high-density lipoprotein cholesterol (HDL-C) increase and, potentially, a reduced cardiovascular disease (CVD) risk. Herein, we describe the discovery of a series of oxadiazole ketones, which upon optimization, led to the identification of compound 12. Compound 12 was evaluated in a mouse pharmacodynamics (PD) model and demonstrated a 56% increase in plasma HDL-C. In a mouse reverse cholesterol transport study, compound 12 stimulated cholesterol efflux by 53% demonstrating HDL-C functionality.

12.
Chemosphere ; 247: 125863, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31972485

RESUMO

Plasma-catalysis technologies (PCTs) have the potential to control the emissions of volatile organic compounds, although their low-energy efficiency is a bottleneck for their practical applications. A plasma-catalyst reactor filled with a CeO2/γ-Al2O3 catalyst was developed to decompose toluene with a high-energy efficiency enhanced by the elevating reaction temperature. When the reaction temperature was raised from 50 °C to 250 °C, toluene conversion dramatically increased from 45.3% to 95.5% and the energy efficiency increased from 53.5 g/kWh to 113.0 g/kWh. Conversely, the toluene conversion using a thermal catalysis technology (TCT) exhibited a maximum of 16.7%. The activation energy of toluene decomposition using PCTs is 14.0 kJ/mol, which is far lower than those of toluene decomposition using TCTs, which implies that toluene decomposition using PCT differs from that using TCT. The experimental results revealed that the Ce3+/Ce4+ ratio decreased and Oads/Olatt ratio increased after the 40-h evaluation experiment, suggesting that CeO2 promoted the formation of the reactive oxygen species that is beneficial for toluene decomposition.

13.
Int J Cardiol ; 300: 262-267, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31685245

RESUMO

BACKGROUND: Obesity is often considered as a risk factor of cardiovascular events, but recent researches showed conflicting results regarding to the effect of body weight on prognosis of coronary artery disease (CAD). This study aimed to evaluate the relationship between body mass index (BMI) and clinical outcomes of CAD in Asian population. METHODS: A total of 4315 patients from the FOCUS registry were enrolled into this analysis. Patients were divided into 4 groups according to BMI: lean group (BMI<18.5 kg/m2), normal group (BMI 18.5-24.9 kg/m2), overweight group (BMI 25-30 kg/m2) and obesity group (BMI>30 kg/m2). Follow-up was continued to 3 years to evaluate clinical outcomes, and the primary endpoint was a composite of all-cause death and myocardial infarction (MI). RESULTS: Patients with higher BMI were more likely to be associated with cardiovascular risk factors like hypertension, hypercholesterolemia and diabetes, but not smoking. At the end of the follow-up period, however, the incidence of a composite endpoint of all-cause death and MI was significantly lower in the higher BMI (overweight and obese) subsets, as compared with the lower BMI group (5.2% vs. 8.0%, p < 0.001). So did the cumulative rates of all-cause death (p < 0.001), cardiovascular death (p < 0.001), and a combined endpoint of cardiovascular death and MI (p = 0.001). CONCLUSIONS: In Asian patients with CAD, an inverse association between BMI and long-term prognosis was observed. Although overweight or obese patients were associated with more metabolism-associated comorbidities, they had significantly lower adverse events at 3-year follow up after percutaneous coronary intervention.

14.
Biotechnol Lett ; 42(2): 197-207, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31786685

RESUMO

OBJECTIVES: Although abnormal expression of early growth response-1 (Egr1) has been revealed in various human solid tumors, the functions and potential mechanisms of Egr1 in the progression of salivary gland pleomorphic adenoma (SGPA) are not entirely understood. RESULTS: An elevated expression of Egr1 was observed both in the human salivary gland pleomorphic adenoma tissues and tumor-initiating cell (TIC) cells, when compared with control group. By loss-of-function assay, the proliferation and invasion capacities of TICs were inhibited, while the cell apoptosis was promoted, which were further evidenced by the protein expression analysis of several key apoptosis-related regulators. Furthermore, TICs with Mithramycin A (an Egr1 inhibitor) treatment achieved the same effects of endogenous Egr1 knockdown. CONCLUSIONS: All these data collectively suggest that Egr1 act as an oncogenic factor in salivary gland pleomorphic adenoma, which may be a potential target for the treatment of SGPA.

15.
Nanotechnology ; 31(13): 135704, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-31796656

RESUMO

The effects of aluminum (Al) on the microstructure, hardness and wear resistance of tungsten-copper (W-Cu) composites were investigated. The W-Cu composites were fabricated via mechanical alloying and spark plasma sintering. It is found that the Al dissolved in the metastable W-Cu alloy can act as an 'intermediary' to hinder the diffusion and phase separation process of Cu out of W during sintering, constructing an interpenetrating nanostructure where Al redistributes in W and Cu. Correspondingly, the hardness of composites increase from 463.4 HV30 to 512.05 HV30 due to Al dissolution and formation of the nanostructure, and their contributions to hardness variation of the original W and Cu regions were distinguished by nanoindentation. In addition, the wear volume was also reduced to less than a third of that of original W-Cu composites without Al addition due to the abundant interfaces and mechanical strengthening, which restricts the removal of W and propagation of cracks during the wear process.

16.
Anal Chem ; 92(2): 2136-2144, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31849210

RESUMO

It remains a technical challenge to accurately identify close species of herbal medicines, especially from adulterants, because of their highly identical phenotypes and chemical compositions. Here, we report a direct, sequencing-free, high-curvature nanostructuring-based electrochemical herb sensor (nanoE-herb sensor) to identify herbal species quickly and accurately using ITS2 barcodes. We engineer a nano-roughened carbon-supported gold nanostructuring array by photolithograph-free, one-step electrodeposition. The 3D fractal nanostructures exhibit a high deflection angle that largely enhances DNA hybridization efficiency, particularly for the midcomplementary hybridization, as compared to the 2D planar surface. More importantly, such a trans-scale array biointerface (including macroscale carbon and nanoscale gold branches) can overcome the detection barrier of slow diffusion of a long genomic sequence and inaccessibility of the sequestered variations in ITS2 secondary structures through the out-protruded 3D functional nanostructures. Our nanoE-herb sensor achieves a detection limit of 0.18 fM for the 64-mer fragment of saffron ITS2 barcode with midhybridization and shows superior specificity against even single-base mismatch. The sensor also precisely differentiates saffron from six other adulterants by directly detecting unpurified asymmetric PCR amplicons (∼500 bp) with ITS2 sequences, suggesting its great potential in the field identification of herbal medicinal species and pathogenic bacteria with specific DNA barcodes.

17.
Int J Biol Macromol ; 145: 197-206, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31870870

RESUMO

Starch nanoparticles (SNPs) have become one of the most interesting nanocarriers due to their relatively easy synthesis, biocompatibility, and biodegradability. However, the practical applications of SNPs are limited, as their aggregation reduce their functionality. Here, SNPs obtained by recrystallizing debranched waxy maize starch were modified using oxygen and ammonia vacuum cold plasma (CP). The modified SNPs were measured using Fourier transform infrared spectroscopy, showing a new carbonyl or carboxyl peak at 1720 cm-1. SNPs modified with oxygen CP treatment have negative charges (-21.6 to -15.1 mV). Modified SNPs with diameter ranging from 75.94 to 159.72 nm had good dispersibility without much aggregation. The relative crystallinity of modified SNPs decreased from 44.13% to 33.80%. Moreover, modified SNPs showed high absorption of tea polyphenols, indicating that as nanocarriers, they can accommodate more cargo molecules than primary SNPs. CP modification of SNPs is simple, green, and inexpensive. Modified SNPs can be used as nanocarriers to deliver drug or food components in the food and pharmaceuticals industries.

18.
J Biochem ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31790140

RESUMO

This study aims to study the effects of intra-nuclear lncRNA MEG3 on the progression of prostate cancer and the underlying mechanisms. Expressions of relative molecules were detected by qRT-PCR and western blot. CHIP and RIP assays were used to evaluate the interaction between intra-nuclear MEG3, histone methyltransferase EZH2 and Engrailed-2 (EN2). The impacts of MEG3 on the viability, proliferation and invasion of prostate cancer cells (PC3) were evaluated by MTT, colony formation and transwell assays, respectively. PC3 cells were transfected with MEG3 and transplanted into nude mice to analyze the effect of MEG3 on tumorigenesis of PC3 cells in vivo. EN2 expression was inversely proportional to MEG3 in the prostate cancer tissues and PC3 cells. RIP results showed that intra-nuclear MEG3 could bind to EZH2. Knockdown of MEG3 and/or EZH2 up-regulated EN2 expression and reduced the recruitment of EZH2 and H3K27me3 to EN2, while over-expressed MEG3 caused opposite effects. MEG3 over-expression suppressed cell viability, colony formation, cell invasion and migration of PC3 cells in vitro and inhibited tumorigenesis of PC3 cells in vivo, while EN2 over-expression diminished the effects. These findings indicated that MEG3 facilitated H3K27 trimethylation of EN2 via binding to EZH2, thus suppressed the development of prostate cancer.

19.
ACS Omega ; 4(23): 20402-20409, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31815244

RESUMO

Coating fertilizer is an effective approach to increase the fertilizer use efficiency and reduce fertilizer application rate. However, only a few studies have focused on coating phosphorus (P) fertilizer, especially diammonium phosphate (DAP) due to its irregular shape and high specific surface area. A novel and low-cost strategy centered on wax-based surface modification and bio-based polymer coating was applied to improve the nutrient characteristics of coated DAP (CDAP). Regular DAP was modified with polyolefin wax and then coated with polyurethanes prepared from castor oil. Experimental results indicated that wax modification significantly decreased the specific surface area, angle of repose of DAP particles, increased the particle hardness, and then facilitated the formation of biopolymer-based coating. The CDAP from wax-modified DAP had better controlled-release performance compared with that from normal DAP. Findings from this study indicate that wax modification can be used as an effective technology to prepare highly efficient controlled-release P fertilizers.

20.
Adv Mater ; : e1906233, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31834665

RESUMO

The development of stimuli-responsive soft actuators, a task largely undertaken by material scientists, has become a major driving force in pushing the frontiers of microrobotics. Devices made of soft active materials are oftentimes small in size, remotely and wirelessly powered/controlled, and capable of adapting themselves to unexpected hurdles. However, nowadays most soft microscale robots are rather simple in terms of design and architecture, and it remains a challenge to create complex 3D soft robots with stimuli-responsive properties. Here, it is suggested that kirigami-based techniques can be useful for fabricating complex 3D robotic structures that can be activated with light. External stress fields introduce out-of-plane deformation of kirigami film actuators made of liquid crystal networks. Such 2D-to-3D structural transformations can give rise to mechanical actuation upon light illumination, thus allowing the realization of kirigami-based light-fuelled robotics. A kirigami rolling robot is demonstrated, where a light beam controls the multigait motion and steers the moving direction in 2D. The device is able to navigate along different routes and moves up a ramp with a slope of 6°. The results demonstrate a facile technique to realize complex and flexible 3D structures with light-activated robotic functions.

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