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1.
Artigo em Inglês | MEDLINE | ID: mdl-31486209

RESUMO

Surface recombination in the photoanode/electrolyte junction seriously impedes photoelectrochemical (PEC) performance. Through coating photoanodes with oxygen evolution catalysts, the photocurrent can be enhanced. But the present system still suffers from high recombination in water splitting. In this work, a novel charge transfer system is successfully designed with using BiVO4 as a prototype. Porphyrins here act as an interfacial charge transfer mediator, like "volleyball setter", to efficiently suppress surface recombination through the higher hole transfer kinetics rather than as a traditional photosensitizer. Furthermore, we find the introduction of "setter" can ensure lifetime of long lived charge carriers at the photoanode/electrolyte interface. Such a simple interface charge modulation system exhibits increased photocurrent density from 0.68 to 4.75 mA cm-2, which provides a promising design strategy for efficient photogenerated charge separation to improve PEC performance.

2.
Mol Biotechnol ; 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31486973

RESUMO

Methyl parathion hydrolase (MPH) plays an important role in degrading a range of organophosphorus compounds. In order to display MPH on the cell surface of Escherichia coli strain RosettaBlue™, the Flavin-based fluorescent protein EcFbFP was severed as an auto-anchoring matrix. With net negative charges of EcFbFP supplying the driving forces, fusion protein MPH-EcFbFP through a two-step auto-surface display process was finally verified by (a) inner membrane translocation and (b) anchoring at outer membrane. Cells with surface-displayed MPH obtained activity of 0.12 U/OD600 against substrate methyl parathion. MPH when fused with engineered EcFbFP containing 20 net negative charges exhibited fivefold higher anchoring efficiency and tenfold higher enzymatic catalytic activity of 1.10 U/OD600. The above result showed that MPH was successfully displayed on cell surface and can be used for biodegradation of methyl parathion.

3.
Hum Cell ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31493246

RESUMO

The objective of this study was to examine the function of the long non-coding RNA (lncRNA) HOXA11-AS in hepatocellular carcinoma (HCC). In total, samples from liver tumor and surrounding normal liver tissues were collected from 66 cases of HCC patients. Normal liver cell line HL-7702 and HCC cell lines HepG2, Hep3B, MHCC-97H and BEL7402 were used. Cells were transfected with different small interference RNAs or vectors. Then, transwell assay, qRT-PCR, CHIP, RIP and Western blot experiments were performed. We found that the HOXA11-AS expression level was higher in HCC samples than surrounding normal liver tissues. And the higher expression level of HOXA11-AS in HCC patients indicated a lower 5-year survival rate. Knockdown of HOXA11-AS in HepG2 and Hep3B cells caused impaired cell invasion and migration abilities. Otherwise, upregulation of HOXA11-AS in MHCC-97H and BEL7402 cells displayed higher invasion and migration capabilities. We also demonstrated that HOXA11-AS could inhibit miR-124 expression by binding to EZH2. Furthermore, overexpression of miR-124 or knockdown EZH2 expression could reverse the HOXA11-AS-induced migration and invasion effects in HCC cells. In summary, the high HOXA11-AS expression in HCC patients is associated with the poor outcome. HOXA11-AS could inhibit miR-124 expression by binding to EZH2 and thus promoted the migration and invasion of HCC cells.

4.
J Phys Chem Lett ; : 5571-5576, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31476868

RESUMO

In this Letter, we analyzed the inductive bias underlying complex free-energy landscapes (FELs) and exploited it to train deep neural networks that yield reduced and clustered representation for the FEL. Our parametric method, called information distilling of metastability (IDM), is end-to-end differentiable and thus scalable to ultralarge data sets. IDM is able to perform clustering in the meantime of reducing the dimensionality. Besides, as an unsupervised learning method, IDM differs from many existing dimensionality reduction and clustering methods in that it requires neither a cherry-picked distance metric nor the ground-true number of clusters defined a priori, and it can be used to unroll and zoom in on the hierarchical FEL with respect to different time scales. Through multiple experiments, we show that IDM can achieve physically meaningful representations that partition the FEL into well-defined metastable states that hence are amenable for downstream tasks such as mechanism analysis and kinetic modeling.

5.
Biomolecules ; 9(9)2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31487971

RESUMO

Designing the "ideal" hydrogel/matrix which can load bone morphogenetic protein-2 (BMP-2) in a low dose and with a sustained release is the key for its successful therapeutic application to enhance osteogenesis. The current use of natural collagen sponges as hydrogel/matrix is limited due to the collagen matrix showing weak mechanical strength and unmanageable biodegradability. Furthermore, the efficiency and safe dose usage of the BMP-2 has never been seriously considered other than purely chasing the lowest dose usage and extended-release time. In this paper, we customized a novel enzymatically cross-linked recombinant human-like collagen (HLC) sponge with low immunogenicity, little risk from hidden viruses, and easy production. We obtained a unique vertical pore structure and the porosity of the HLC, which are beneficial for Mesenchymal stem cells (MSCs) migration into the HLC sponge and angiopoiesis. This HLC sponge loading with low dose BMP-2 (1 µg) possessed high mechanical strength along with a burst and a sustained release profile. These merits overcome previous limitations of HLC in bone repair and are safer and more sensitive than commercial collagens. For the first time, we identified that a 5 µg dose of BMP-2 can bring about the side effect of bone overgrowth through this sensitive delivery system. Osteoinduction of the HLC-BMP sponges was proved by an in vivo mouse ectopic bone model and a rat cranial defect repair model. The method and the HLC-BMP sponge have the potential to release other growth factors and aid other tissue regeneration. Additionally, the ability to mass-produce HLC in our study overcomes the current supply shortage, which limits bone repair in the clinic.

6.
Biomed Environ Sci ; 32(8): 571-577, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31488233

RESUMO

OBJECTIVE: The aim of this study was to determine whether low calf circumference (CC) could predict nutritional risk and the cutoff values of CC for predicting nutritional risk in hospitalized patients aged ⪖ 80 years. METHODS: A total of 1,234 consecutive patients aged ⪖ 80 years were enrolled in this study. On admission, demographic data, CC, and laboratory parameters were obtained. Patients with Nutritional Risk Screening 2002 (NRS-2002) total score ⪖ 3 were considered as having nutritional risk. RESULTS: CC values were significantly lower in patients with nutritional risk compared to those in patients without nutritional risk [27.00 (24.50-31.00) vs. 31.00 (29.00-33.50], P < 0.001]. CC was negatively correlated with age and nutritional risk scores. Logistic regression analysis of nutritional risk revealed that body mass index, albumin level, hemoglobin level, cerebral infarction, neoplasms, and CC (OR, 0.897; 95% confidence interval, 0.856-0.941; P < 0.001) were independent impact factors of nutritional risk. Nutritional risk scores increased with a decrease in CC. In men, the best CC cutoff value for predicting nutritional risk according to the NRS-2002 was 29.75 cm. In women, the cutoff value was 28.25 cm. CONCLUSION: CC is a simple, noninvasive, and valid anthropometric measure to predict nutritional risk for hospitalized patients aged ⪖ 80 years.

7.
Biosens Bioelectron ; 144: 111643, 2019 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31499389

RESUMO

An electrochemical biosensor was proposed utilizing an improved amplification strategy for the rapid detection of sulfamethazine (as a model target) in aquatic environments. In this competitive immunoassay, cetyltrimethylammonium bromide-capped gold nanoparticles (CTAB-AuNPs) were used as a signal amplifier and electrode matrix and coated with an antigen-antibody (Cag-Ab1) specific binding system as a recognition unit for the target compound. In addition, silver nanoparticle labels were functionalized with dendritic fibrous nanosilica (DFNS@AgNPs) and decorated onto chitosan/single walled carbon nanohorn (CS/SWCNH)-modified glass carbon electrodes (GCEs), which improved the electron transfer rate and increased the surface area, enabling more coating antigens to be captured. Under acidic conditions, massive amounts of the Ag+ bound to the surface of the AuNPs dissolved, and consequently, formed Ag+@CTAB-AuNP complexes, which resulted in a distinctly improved peroxidase-like activity and enhanced current response. Furthermore, the destroyed Ab1-Ab2-DFNS conjugation greatly decreased the impedance, bringing about the amplification of the electrochemical signals. After optimization of the parameters, the proposed approach exhibited excellent performance, including good sensitivity (LOD, 0.0655 ng/mL) and satisfactory accuracy (recoveries, 79.02%-118.39%; CV, 3.18%-9.82%), which indicates the great potential of this strategy for the rapid detection of trace pollutants in the environments.

8.
J Hazard Mater ; 383: 121156, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31505427

RESUMO

LaMnO3-based catalysts with perovskite structure have gained increasing interest for Hg0 oxidation owing to their excellent catalytic activity, high thermal stability and unique redox behavior. Understanding the Hg0 oxidation behavior on LaMnO3 will broaden the application of LaMnO3-based perovskites in Hg0 removal field. Density functional theory (DFT) calculations were conducted to examine the catalytic mechanism of Hg0 oxidation by HCl on LaMnO3 surface. The results indicate that Mn-terminated LaMnO3(010) surface is more active and stable than La-terminated surface. Hg0 and HgCl2 are chemisorbed on LaMnO3(010) surface. HgCl can be molecularly chemisorbed on LaMnO3(010) and serve as an intermediate in Hg0 oxidation reaction. HCl dissociatively adsorbs on LaMnO3(010) and generates surface active chlorine complexes. Langmuir-Hinshelwood mechanism, where the chemisorbed Hg0 reacts with the dissociatively adsorbed HCl, is responsible for Hg0 oxidation by HCl on LaMnO3(010). Catalytic Hg0 oxidation over the surface contains four-steps: Hg0 → Hg(ads) → HgCl(ads) → HgCl2(ads) → HgCl2, and the second step (Hg(ads) → HgCl(ads)) is the rate-determining step because of its relatively larger energy barrier (0.74 eV).

9.
ACS Nano ; 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31496233

RESUMO

Collagen is the most abundant structural protein in soft tissues, and the duplication of its structure and mechanics represents a key challenge to nanotechnology. Here we report a fibrous supramolecular network that can mimic nearly all of the aspects of collagen from dynamic hierarchical architecture to nonlinear mechanical behavior. This complex self-assembly system is solely based on a glucose polymer: curdlan, which is synthesized by bacteria and can form a similar triple helix as collagen. Triggered by solvent and temperature cues, free curdlan chains wind into superhelical trimers, and the trimers then bundle hexagonally into nanofibers of 20-40 nm in diameter. The fibers are interconnected in a water-rich 3D network structure. The network is highly dynamic and stress-responsive, which can shift from isotropic to anisotropic organization by the winding/unwinding of stress-induced interfiber triple helical net-points. Mechanical tests show that these nanofiber networks exhibit similar nonlinear elasticity as collagenous tissues including skin and tendon. The supramolecular networks also display a very wide range of tensile strength from ∼60 KPa to ∼50 MPa depending on the specific network organization. These biomimetic and dynamic supernetworks may have applications in tissue engineering, drug delivery systems, artificial skin, and soft robotics.

10.
Sensors (Basel) ; 19(18)2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31505866

RESUMO

The privacy and security of the Internet of Things (IoT) are emerging as popular issues in the IoT. At present, there exist several pieces of research on network analysis on the IoT network, and malicious network analysis may threaten the privacy and security of the leader in the IoT networks. With this in mind, we focus on how to avoid malicious network analysis by modifying the topology of the IoT network and we choose closeness centrality as the network analysis tool. This paper makes three key contributions toward this problem: (1) An optimization problem of removing k edges to minimize (maximize) the closeness value (rank) of the leader; (2) A greedy (greedy and simulated annealing) algorithm to solve the closeness value (rank) case of the proposed optimization problem in polynomial time; and (3)UpdateCloseness (FastTopRank)-algorithm for computing closeness value (rank) efficiently. Experimental results prove the efficiency of our pruning algorithms and show that our heuristic algorithms can obtain accurate solutions compared with the optimal solution (the approximation ratio in the worst case is 0.85) and outperform the solutions obtained by other baseline algorithms (e.g., choose k edges with the highest degree sum).

11.
J Leukoc Biol ; 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31509299

RESUMO

Innate immune responses need to be precisely controlled to avoid prolonged inflammation and prevent unwanted damage to the host. Here, we report that RNF144B responded dynamically to LPS stimulation and negatively regulated LPS-induced inflammation. We found that RNF144B interacted with the scaffold/dimerization domain (SDD) of TANK binding kinase 1 (TBK1) through the in between RING (IBR) domain to inhibit its phosphorylation and K63-linked polyubiquitination, which led to TBK1 inactivation, IRF3 dephosphorylation, and IFN-ß reduction. RNF144B knockdown with siRNA increased IRF3 activation and IFN-ß production in response to LPS stimulation. Our study identifies that RNF144B interaction with TBK1 is sufficient to inactivate TBK1 and delineates a previously unrecognized role for RNF144B in innate immune responses.

12.
Injury ; 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31447208
13.
J Craniofac Surg ; 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31449217

RESUMO

Maxillary hypoplasia is a common developmental deformity affecting patients with cleft lip and palate. Various surgical techniques including conventional orthognathic surgery, total maxillary distraction osteogenesis, and anterior maxillary segmental distraction have been applied to address the deformity. With the evolution of 3D computed tomography imaging, the visualization of skeletal complexities in different perspectives is greatly enhanced and comprehensive surgical planning is achieved. Intraoperative efficiency is also improved with the fabrication of 3D-printed templates. The study aims to present different surgical techniques with virtual surgical planning (VSP) and 3D-printed surgical templates and the solution of representative cases. From January 2014 to January 2019, VSP was transferred to actual surgery or distraction precisely in 80 adult patients with cleft-related maxillary hypoplasia. The accuracy was analyzed and the relapse was also estimated and observed in 18 patients after 1-year follow-up. Based on our experience, VSP provides a more reliable and effective option to conventional model surgery. It facilitates the preoperative planning and accurately transfers the virtual plan to correct the cleft-related maxillary hypoplasia.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31402413

RESUMO

This study was aimed to investigate the correlation between left ventricular (LV) myocardial strain and LV geometry in healthy adults using cardiovascular magnetic resonance-feature tracking (CMR-FT). 124 gender-matched healthy adults who underwent healthy checkup using CMR cine imaging were retrospectively analyzed. Peak global radial, circumferential, longitudinal strain (GRS, GCS and GLS) for left ventricle were measured. LV geometry was assessed by the ratio of LV mass (LVM) and end-diastolic volume (EDV). GRS, GCS and GLS were 34.18 ± 6.71%, - 22.17 ± 2.28%, - 14.76 ± 2.39% for men, and 33.40 ± 6.95%, - 22.49 ± 2.27%, - 15.72 ± 2.36% for women. Multiple linear regression showed that LVM/EDV was associated with decreased GLS (ß = - 0.297, p = 0.005), but was not significantly associated with GRS and GCS (both p > 0.05). There was an increase in the magnitude of GRS, GCS and GLS with advancing age (ß = 0.254, ß = 0.466 and ß = 0.313, all p < 0.05). Greater BMI was associated with decreased GRS, GCS and GLS (ß = - 0.232, ß = - 0. 249 and ß = - 0.279, all p < 0.05). In conclusion, compared with GRS and GCS, GLS is more sensitive to assess LV concentric remodeling in healthy adults. GRS, GCS and GLS are all independently positively associated with age and negatively associated with BMI. Sex-based LV strain reference values for healthy Chinese adults are established.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31403441

RESUMO

Homozygous and heterozygous deletions commonly exist in the human genome. For current structural variation detection tools, it is significant to determine whether a deletion is homozygous or heterozygous. However, the problems of sequencing errors, micro-homologies and micro-insertions prohibit common alignment tools from identifying accurate breakpoint locations, and often result in detecting false structural variations. In this paper, we present a novel deletion detection tool called Sprites2. Comparing with Sprites, Sprites2 makes the following modifications: (1) The distribution of insert size is used in Sprites2, which can identify the type of deletions and improves the accuracy of deletion calls; (2) A precise alignment method based on AGE (one algorithm simultaneously aligning 5' and 3' ends between two sequences) is adopted in Sprites2 to identifying breakpoints, which is helpful to resolve the problems introduced by sequencing errors, micro-homologies and micro-insertions. In order to test and verify the performance of Sprites2, some simulated and real datasets are adopted in our experiments, and Sprites2 is compared with five popular tools. According to the experimental results, we can find that Sprites2 can improve deletion detection performance. Sprites2 can be downloaded from https://github.com/zhangzhen/sprites2.

16.
J Exp Clin Cancer Res ; 38(1): 365, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31429766

RESUMO

BACKGROUND: The lncRNA LINC00460 plays crucial roles in several epithelial cancers, although its mechanisms of action differ greatly in different cellular contexts. In this study, we aimed to determine the potential clinical applications of LINC00460 and elucidate the mechanisms by which LINC00460 affects the development and progression of head and neck squamous cell carcinoma (HNSCC). METHODS: The biological functions of LINC00460 were assessed in several epithelial cancer cell lines. The subcellular localization of LINC00460 was evaluated by cell nuclear/cytoplasmic fractionation and fluorescence in situ hybridization. RNA pull-down assays, LS-MS/MS analysis, and RNA and chromatin immunoprecipitation assays were performed to identify the molecular mechanism by which LINC00460 promotes HNSCC progression. The clinical pathological features of LINC00460 and PRDX1 were evaluated in HNSCC tissues and paired adjacent normal tissues. RESULTS: LINC00460 enhanced HNSCC cell proliferation and metastasis in vitro and in vivo and induced epithelial-mesenchymal transition (EMT). LINC00460 primarily localized within the cytoplasm of HNSCC cells, physically interacted with PRDX1 and facilitated PRDX1 entry into the nucleus. PRDX1 promoted the transcription of LINC00460, forming a positive feedback loop. In addition, PRDX1 also promoted the transcription of EMT-related genes (such as ZEB1, ZEB2 and VIM) through enrichment on gene promoters in the nucleus. LINC00460 effectively induced HNSCC cell EMT in a PRDX1-dependent manner, and PRDX1 mainly mediated the EMT-promoting effect of LINC00460. High levels of LINC00460 and PRDX1 expression were positively associated with lymph metastasis, pathological differentiation and tumor size in HNSCC patients. CONCLUSIONS: LINC00460 promoted EMT in HNSCC cells by facilitating PRDX1 entry into the nucleus. LINC00460 and PRDX1 are promising candidate prognostic predictors and potential targets for cancer therapy for HNSCC.

17.
Environ Pollut ; 254(Pt A): 112938, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31404731

RESUMO

In the present study, the competitive adsorption of Cu2+, Pb2+, and Cd2+ by a novel natural adsorbent (i.e., argillaceous limestone) modified with chitosan (C-AL) was investigated. The results demonstrated that both intraparticle diffusion and chemisorption marked significant contributions to the Cu2+ adsorption process by both raw argillaceous limestone (R-AL) and C-AL in mono-metal adsorption systems. Antagonism was found to be the predominant competitive effect for Cu2+, Pb2+ and Cd2+ adsorptions by C-AL in the multi-metal adsorption system. The three-dimensional simulation and FTIR analysis revealed that the presence of Cu2+ suppressed Pb2+ and Cd2+ adsorptions, while the effect of Cd2+ on Cu2+ and Pb2+ adsorptions was insignificant. The spectroscopic analyses evidenced that amide groups in C-AL played a crucial role in metal adsorption. The preferential adsorptions of Pb2+ > Cu2+ > Cd2+ were likely due to the different affinities of the metals to the lone pair of electrons on the N atom from the amide groups and/or the O atoms from the -OH and -COO- groups on C-AL. The interactions between C-AL and metal ions and between various metal species influenced their competitive adsorption behaviors. C-AL exhibited a superior metal adsorption capacity in comparison with that the capacities of other natural adsorbents reported during the last decade, suggesting its potential practical applications.

18.
Nanotechnology ; 30(45): 455303, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31394513

RESUMO

Solid-state nanopores have drawn considerable attention for their potential applications in DNA sequencing and nanoparticle analysis. However, fabrication of nanopores, especially those of diameter below 30 nm, requires sophisticated techniques. Here, a versatile method to controllably reduce the diameter of prefabricated large-size pores down to sub-30 nm without greatly increasing the effective pore depth from the original membrane thickness is shown. This method exploits carbon deposition achieved via hydrocarbon evaporation, induced by an incident beam of electrons, and subsequent dissociation of hydrocarbon to solid carbon deposits. The carbon deposition employs a conventional scanning electron microscope equipped with direct visual feedback, along with a stable hydrocarbon source nearby the sample. This work systematically studies how electron beam accelerating voltage, imaging magnification, initial pore size and membrane composition affect the process of pore size reduction. Secondary electrons generated in the membrane material are confirmed to be the main cause of the dissociation of hydrocarbon. Thicker carbon deposited on one side than on the other of the membrane results in an asymmetric nanopore shape and a rectifying ionic transport. A physico-phenomenological model combined with Monte Carlo simulations is proposed to account for the observed carbon deposition behaviors.

19.
Nat Commun ; 10(1): 3876, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462636

RESUMO

The salinity gradient between seawater and river water is a clean energy source and an alternative solution for the increasing energy demands. A membrane-based reverse electrodialysis technique is a promising strategy to convert osmotic energy to electricity. To overcome the limits of traditional membranes with low efficiency and high resistance, nanofluidic is an emerging technique to promote osmotic energy harvesting. Here, we engineer a high-performance nanofluidic device with a hybrid membrane composed of a silk nanofibril membrane and an anodic aluminum oxide membrane. The silk nanofibril membrane, as a screening layer with condensed negative surface and nanochannels, dominates the ion transport; the anodic aluminum oxide membrane, as a supporting substrate, offers tunable channels and amphoteric groups. Thus, a nanofluidic membrane with asymmetric geometry and charge polarity is established, showing low resistance, high-performance energy conversion, and long-term stability. The system paves avenues for sustainable power generation, water purification, and desalination.

20.
Semin Cancer Biol ; 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31445220

RESUMO

More than 70% of gastrointestinal (GI) cancers are diagnosed with metastases, leading to poor prognosis. For some cancer patients with limited sites of metastatic tumors, the term oligometastatic disease (OMD) has been coined as opposed to systemic polymetastasis (PMD) disease. Stephan Paget first described an organ-specific pattern of metastasis in 1889, now known as the "seed and soil" theory where distinct cancer types are found to metastasize to different tumor-specific sites. Our understanding of the biology of tumor metastasis and specifically the molecular mechanisms driving their formation are still limited, in particular, as it relates to the genesis of oligometastasis. In the following review, we discuss recent advances in general understanding of this metastatic behavior including the role of specific signaling pathways, various molecular features and biomarkers, as well as the interaction of carcinoma cells with their tissue microenvironments (both primary and metastatic niches). The unique features that underlie OMD provide potential targets for localized therapy. As it relates to clinical practice, OMD is emerging as treatable with surgical resection and/or other local therapy options. Strategies currently being applied in the clinical management of OMD will be discussed including surgical, radiation-based therapy, ablation procedures, and the results of emerging clinical trials involving immunotherapy.

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