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1.
J Phys Condens Matter ; 32(6): 065001, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31631885

RESUMO

Rational design of novel two-dimensional (2D) electrode materials with high capacity is crucial for the further development of Li-ion and Na-ion batteries. Herein, based on first-principles calculations, we systemically investigate Li and Na storage behaviors in the recently discovered 2D topological nodal-loop metal-the honeycomb borophene oxide (h-B2O). We show that h-B2O is an almost ideal anode material. It has good conductivity before and after Li/Na adsorption, fast ion diffusion with diffusion barrier less than 0.5 eV, low open-circuit voltage (<1 V), and small lattice change (<6.2%) during intercalation. Most remarkably, its theoretical storage capacity is extremely high, reaching up to 2137 mAh · g-1 for Li and 1425 mAh · g-1 for Na. Its Li storage capacity is more than six times higher than graphite (~372 mAh · g-1), and is almost the highest among all 2D materials discovered to date. Our results strongly suggest that 2D h-B2O is an exceedingly promising anode material for both Li- and Na-ion batteries with super high capacity.

2.
Nanotechnology ; 31(2): 025601, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31518998

RESUMO

In this study, a novel photocatalyst composed of N-doped TiO2 (N-TiO2) and (Ca, Y)F2:Yb3+, Tm3+ was prepared by simple dealloying followed by a hydrothermal method. The composite exhibits a homogeneous nanoporous structure consisting of large quantities of the spindle-like N-doped TiO2 nanorods, on which the (Ca, Y)F2:Yb3+, Tm3+ particles with a diameter of around 5 nm are uniformly dispersed. In addition, morphology and property of the N-TiO2 can be controlled by adjusting the dealloying period. Results show that a short immersion time leads to a small size, large surface area and low band gap. As a result, the N-TiO2/(Ca, Y)F2:Yb3+, Tm3+ composite after dealloying for 48 h (TiO2-48-C) exhibits higher degradation rates (65.6% for 10 h irradiation by 980 nm NIR) than others after dealloying for 60 h (TiO2-60-C) and 72 h (TiO2-72-C), indicating its excellent potential for practical applications.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31799699

RESUMO

Telomeres are specialized genomic structures that protect chromosomal ends to maintain genomic stability. Telomeric length is primarily regulated by the telomerase complex, essentially consisting of an RNA template (TERC), an enzymatic subunit (telomerase reverse transcriptase, TERT). In humans, telomerase activity is repressed during embryonic differentiation and is absent in most somatic cells. However, it is upregulated or reactivated in 80-90% of the primary tumors in humans. The human TERT (hTERT) plays a pivotal role in cellular immortality and tumorigenesis. However, the molecular mechanisms of telomerase functioning in cancer have not been fully understood beyond the telomere maintenance. Several research groups, including ours have demonstrated that hTERT possesses vital functions independent of its telomere maintenance, including angiogenesis, inflammation, cancer cell stemness, and epithelial-mesenchymal transformation (EMT). All these telomere-independent activities of hTERT may contribute to the regulation of the dynamics and homeostasis of tumor microenvironment (TME), thereby promoting tumor growth and development. Cancer progression and metastasis largely depend upon the interactions between cancer cells and their microenvironment. In this review, the involvement of TERT in tumor microenvironment and the underlying implications in cancer therapeutics have been summarized.

4.
Inorg Chem ; 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31793291

RESUMO

A new strategy for a G-quadruplex fluorescent probe based on a nitro-substituted ruthenium complex is described. G-quadruplex DNA can be distinguished from double- or single-strand DNA by the naked eye. This ability originates from variation of the degree of protection of the nitro group on the complex from water by G-quadruplex and other structure DNAs.

5.
Chemosphere ; 241: 125114, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31683445

RESUMO

Di-(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer. It has neurotoxicity and exposure to it causes impairment of neurodevelopment, behavior and cognition. However, the molecular mechanisms responsible for the DEHP-induced neurotoxicity are not yet clearly defined. Tumor necrosis factor-induced protein 1 (TNFAIP1) was first discovered in umbilical vein endothelial cells and was further found to be important in the progress of Alzheimer's disease. Herein we explore the mechanism of TNFAIP1 in DEHP-induced neurotoxicity with the involvement of cyclic AMP response elements binding protein (CREB) signaling pathway in a mouse neuroblastoma cell line (N2a cells). We found that exposure to DEHP induced apoptosis and downregulated the expression of brain-derived neurotrophic factor (BDNF), synaptic proteins PSD 95 and synapsin-1 while upregulated the expression of TNFAIP1 and decreased the levels of phosphorylated Akt, CaMK Ⅳ, catalytic subunits of PKA and CREB in CREB signaling pathway. Knockdown of TNFAIP1 using TNFAIP1 small interfering RNA (siRNA) expression vector prevented DEHP from inhibiting CREB pathway, thus reduced apoptosis and restored expression of BDNF, PSD 95 and synapsin-1. Our data indicate that downregulation of TNFAIP1 prevents DEHP-induced neurotoxicity via activating CREB pathway. Therefore, TNFAIP1 is a potential target for relieving the DEHP-induced neurotoxicity and related neurological disorders.

6.
Opt Express ; 27(22): 31874-31888, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684411

RESUMO

A dual-optimized adaptive Kalman filtering (DO-AKF) algorithm based on back propagation (BP) neural network and variance compensation was developed for high-sensitivity trace gas detection in laser spectroscopy. The BP neural network was used to optimize the Kalman filter (KF) parameters. Variance compensation was introduced to track the state of the system and to eliminate the variations in the parameters of dynamic systems. The proposed DO-AKF algorithm showed the best performance compared with the traditional multi-signal average, extended KF, unscented KF, KF optimized by BP neural network (BP-KF) and KF optimized by variance compensation (VC-KF). The optimized DO-AKF algorithm was applied to a QCL-based gas sensor system for an exhaled CO analysis. The experimental results revealed a sensitivity enhancement factor of 23. The proposed algorithm can be widely used in the fields of environmental pollutant monitoring, industrial process control, and breath gas diagnosis.

7.
Nat Cell Biol ; 21(11): 1303-1304, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31685985
8.
Nat Nanotechnol ; 14(11): 1048-1055, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31686005

RESUMO

Many living organisms track light sources and halt their movement when alignment is achieved. This phenomenon, known as phototropism, occurs, for example, when plants self-orient to face the sun throughout the day. Although many artificial smart materials exhibit non-directional, nastic behaviour in response to an external stimulus, no synthetic material can intrinsically detect and accurately track the direction of the stimulus, that is, exhibit tropistic behaviour. Here we report an artificial phototropic system based on nanostructured stimuli-responsive polymers that can aim and align to the incident light direction in the three-dimensions over a broad temperature range. Such adaptive reconfiguration is realized through a built-in feedback loop rooted in the photothermal and mechanical properties of the material. This system is termed a sunflower-like biomimetic omnidirectional tracker (SunBOT). We show that an array of SunBOTs can, in principle, be used in solar vapour generation devices, as it achieves up to a 400% solar energy-harvesting enhancement over non-tropistic materials at oblique illumination angles. The principle behind our SunBOTs is universal and can be extended to many responsive materials and a broad range of stimuli.

9.
Chem Biol Interact ; 315: 108869, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31682803

RESUMO

Spermatogenic dysfunction is one of the major secondary complications of male diabetes. Salidroside (SAL) is the important active ingredients isolated from Herba Cistanche, which exhibits numerous pharmacological activities such as antioxidant, anti-diabetic, and anti-inflammatory effects. The present study was designed to determine whether SAL contributes to the recovery from spermatogenic dysfunction in streptozotocin (STZ) induced type-1 diabetic mice. SAL (25, 50, or 100 mg/kg) and Clomiphene citrate (CC, 5 mg/kg) were orally administered to male type-1 diabetic mice for 10 weeks. Testis tissues were collected for histopathological and biochemical analysis. Moreover, reproductive organ weight, sperm parameters, and testicular cell DNA damage were estimated. The results revealed that SAL significantly improved the weight of the reproductive organs, sperm parameters and testicular morphology to different degrees in type-1 diabetic mice. Furthermore, reactive oxygen species (ROS) and malondialdehyde (MDA) levels were significantly reduced, and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), markedly increased in the testicular tissue after SAL treatment. In addition, our data also showed a marked downregulation the fluorescence expressions of p38 MAPK phosphorylation and upregulation the protein expressions of ZO-1, Occludin, Claudin-11 and N-cadherin after SAL administration (100 mg/kg) compared with the type-1 diabetic group. In conclusion, these results demonstrated that SAL exerts protective effects on type-1 diabetes-induced male spermatogenic dysfunction, which is likely mediated by inhibiting oxidative stress-mediated blood testis barrier damage.

10.
Stem Cell Res ; 41: 101635, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31707215

RESUMO

Autism spectrum disorder (ASD) is a childhood-onset neurodevelopmental disorder challenged in social reciprocity and restrictive repetitive behaviors. Here, we generated an induced pluripotent stem cell (iPSC) line SDQLCHi014-A from a patient with ASD and hyperactivity, carrying a 303 kb de novo deletion at chr3p26.1 implicating GRM7 gene by reprogramming urine cells with non-integrating vectors. SDQLCHi014-A have shown full pluripotency, differentiation capacity and genetic stability. This iPSC line provides a valuable resource to study the molecular mechanisms underlying ASD.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31741371

RESUMO

One of the greatest challenges for wearable electronics is the lack of virtually flexible electrodes with satisfactory electrochemical performance, and there is always a "softness vs effective capacity" dilemma. Herein, a polymer electrode is proposed. The carefully chosen and partially conjugated polyimide realizes the dual function of a flexible agent and an active agent. The softness of the electrode is rendered by the polymer, while the carbon nanotube ensures electron transfer (ET) within the polymer. A modified electrospinning method has been used in the preparation of a carbon nanotube (CNT)-intertwined polyimide (PI) film. The binder-free and current collector-free polymer electrode has as high as 80% active phase and releases near-theoretical capacity accompanied by very stable cycling up to 200 cycles. Owing to the dual role of the polymer component, the softness vs effective capacity dilemma has been well addressed. Aiming at the practical application, a fatigue test has been first conducted in a practical mode and the well-reserved electrochemical activity under extreme stress change as well as in plenty of electrolyte has been revealed. The work realizes that the flexible electrode well fulfills the requirement and sheds more light on the application of the polymer electrode materials.

12.
Int J Biol Macromol ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31730965

RESUMO

In the present study, the in vitro anti-inflammatory activity of four purified polysaccharides (CLGP1, CLGP2, CLGP3 and CLGP4) extracted from edible green algae Caulerpa lentillifera was evaluated. As a result, CLGP4 exhibited more effectively inhibitory effect on LPS-induced HT29 cells, including reducing the production of IL-1ß, TNF-α, SIgA and mucin2, and decreasing the expression of IL-1ß and TNF-α. According to the results, CLGP4 showed a better anti-inflammatory effect, might highly related to the presence of sulfate groups. Furthermore, the structure of CLGP4 was analyzed by methylation analysis, GC-MS and NMR spectroscopy. It was found that CLGP4 was a novel xylogalactomanan consisting of ß-(1 â†’ 4)-Manp, →2,4)Manp(1→, ß-(1 â†’ 2)-Manp, ß-(1 â†’ 3)-Galp, ß-(1 â†’ 4)-Xylp, terminal ß-Galp and terminal ß-Xylp residues. Additionally, the sulfate groups were located on C-3 of â†’4)Xylp(1→, C-6 of â†’3)Galp(1→ and C-3 of â†’2)Manp(1→. These results could enlarge the potential application of CLGP4 as functional ingredient to attenuate inflammation.

13.
Circ Res ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730408

RESUMO

Rationale: Genome editing by CRISPR/Cas9 is evolving rapidly. Recently, second generation CRISPR/Cas9 activation systems based on nuclease inactive "dead" (d)Cas9 fused to transcriptional transactivation domains were developed for directing specific guide (g)RNAs to regulatory regions of any gene of interest, to enhance transcription. The application of dCas9 to activate cardiomyocyte transcription in targeted genomic loci in vivo has not been demonstrated so far. Objective: We aimed to develop a mouse model for cardiomyocyte-specific, CRISPR-mediated transcriptional modulation, and to demonstrate its versatility by targeting Mef2d and Klf15 loci (two well-characterized genes implicated in cardiac hypertrophy and homeostasis) for enhanced transcription.Methods and Results: A mouse model expressing dCas9 with the VPR transcriptional transactivation domains under the control of the myosin heavy chain (Myh) 6 promotor was generated. These mice innocuously expressed dCas9 exclusively in cardiomyocytes. For initial proof-of-concept, we selected Mef2d, which when overexpressed, led to hypertrophy and heart failure, and Klf15, which is lowly expressed in the neonatal heart. The most effective gRNAs were first identified in fibroblast (C3H/10T1/2) and myoblast (C2C12) cell lines. Using an improved triple gRNA expression system (TRISPR), up to three different gRNAs were transduced simultaneously to identify optimal conditions for transcriptional activation. For in vivo delivery of the validated gRNA combinations, we employed systemic administration via adeno-associated virus serotype (AAV) 9. Upon gRNA delivery targeting Mef2d expression, we recapitulated the anticipated cardiac hypertrophy phenotype. Using gRNA targeting Klf15, we could enhance its transcription significantly, although Klf15 is physiologically silenced at that time point. We further confirmed specific and robust dCas9VPR on-target effects.Conclusions: The developed mouse model permits enhancement of gene expression by utilizing endogenous regulatory genomic elements. Proof-of-concept in two independent genomic loci suggests versatile applications in controlling transcription in cardiomyocytes of the postnatal heart.

14.
Front Immunol ; 10: 2392, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681285

RESUMO

Background: Stroke patients with diabetes suffer from higher mortality rate and worsened neurological outcome. However, the responses of immune system to cerebral ischemia in the setting of diabetes remain poorly understood. Methods: In this study, we investigated the temporal profile of leukocyte mobilization and brain infiltration following distal middle cerebral artery occlusion (dMCAO) in db/db mouse model of type 2 diabetes (T2D) and its db/+ normoglycemic controls. Results: We found a significant increase of brain-infiltrating CD4+ T cell at day 3 after dMCAO, and a delayed and dramatic increase of brain-infiltrating neutrophils, CD4+ T cells, CD8+ T cells, and B cells at day 7 after dMCAO in db/db mice vs. db/+ controls. Leukocyte subsets in the circulation and spleen were also measured, however, there is no significant difference between non-diabetic and diabetic groups. Furthermore, we identified an increased expression of activation marker CD69 in brain-infiltrating neutrophils, CD4+ T and CD8+ T cells, and IFN-γ in brain-infiltrating CD4+ T cells in db/db mice at day 7 after dMCAO. Conclusions: These findings for the first time demonstrate that cerebral ischemia induces a delayed and sustained augmentation of brain infiltration and activation of neutrophils and lymphocytes in type 2 diabetic mice and these altered immune responses might contribute to the severer brain tissue damage and worse neurological outcomes of diabetes stroke, which warrants further investigation.

15.
Mikrochim Acta ; 186(12): 757, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31707541

RESUMO

A disposable visual microfluidic immunosensor is described for the determination of foodborne pathogens using immunomagnetic separation, enzymatic catalysis and distance indication. Specifically, a sensor was designed to detect Salmonella typhimurium as a model pathogen. Magnetic nanoparticles (MNPs) were modified with the anti-Salmonella monoclonal antibodies and then used to enrich S. typhimurium from the sample. This is followed by conjugation to polystyrene microspheres modified with anti-Salmonella polyclonal antibodies and catalase to form the MNP-bacteria-polystyrene-catalase sandwich. The catalase on the complexes catalyzes the decomposition of hydrogen peroxide to produce oxygen after passing a micromixer. The generated oxygen gas increases the pressure in the chip and pushes the indicating red dye solution to travel along the channel towards the unsealed outlet. The travel distance of the red dye can be visually read and related to the amount of S. typhimurium using the calibration scale. The sensor can detect as low as 150 CFU·mL-1 within 2 h. Graphical abstractSchematic representation of the distance-based microfluidic immunosensor for visual detection of foodborne bacteria using immunomagnetic nanoparticles for bacteria separation, catalase for decomposition of hydrogen peroxide to form oxygen which causes a pressure increase, and red dyed particles movement for distance indication.

16.
Nanotechnology ; 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31726449

RESUMO

Cupper sulfide (CuS) is considered as a promising anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity and good electrical conductivity. However, inferior cycle performance and low coulombic efficiency of CuS caused by structure detoriation and degradation and the "shuttling effect" of polysulfide intermediates are restricting its practical application. In this work, we report a facile method to generate S vacancies (Vs) in CuS nanoflowers by thermal annealing in Ar. The obtained CuS was composited with reduced graphene oxide (rGO) to prepared an anode for LIBs. The existence of vacancy defects in CuS could lead to the electron delocalization and excitation, which are responsible for the conductivity improvement and fast charge transport kinetics. Meanwhile, the graphene coating layer ensures fast pathways for Li+ ions diffusion and provide a strong physical adsorption of the polysulfides. Furthermore, hierarchical CuS spheres composed of ultrathin nanosheets provide large void space to accommodate the volume expansion of CuS. The synthesized composite exhibited a high initial discharge capacity of 882 mAh g-1 and exhibited stable cyclability along with around 99% coulombic efficiency over 100 cycles. The results of this work reveal that Vs-CuS/rGO composites are promising anodes to enhance the performance of next-generation lithium-ion batteries.

17.
Biosens Bioelectron ; : 111862, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31740256

RESUMO

Salmonella is the leading risk factor in food safety. Rapid, sensitive and accurate detection of Salmonella is a key to prevent and control the outbreaks of foodborne diseases caused by Salmonella. In this study, we reported a colorimetric biosensor for ultrasensitive detection of Salmonella Typhimurium using a magnetic grid separation column to efficiently separate target bacteria from large volume of sample and platinum loaded zeolitic imidazolate framework-8 (Pt@ZIF-8) nanocatalysts to effectively amplify biological signal. The target Salmonella cells in large volume of sample were first separated and concentrated using the magnetic grid separation column with immune magnetic particle chains, then conjugated with the immune Pt@ZIF-8 nanocatalysts to mimic peroxidase for catalysis of hydrogen peroxide-3,3',5,5'-tetramethylbenzidine, and finally determined by measuring the catalysate at characteristic wavelength of 450 nm. This proposed biosensor was able to separate ∼70% of target Salmonella cells from 50 mL of bacterial sample and quantitatively detect Salmonella from 101 to 104 CFU/mL in 2.5 h with the lower detection limit of 11 CFU/mL. The mean recovery for Salmonella in spiked chicken carcass was about 109.8%. This new magnetic grid separation method was first time reported for efficient separation of target bacteria from very large volume of sample to greatly improve the sensitivity of this biosensor and could be used with various biosensing assays for practical applications in routine detection of foodborne pathogens without any bacterial pre-enrichment.

18.
Biochem Cell Biol ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31742425

RESUMO

The purpose of the current study is to characterize the expression of procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2 (PLOD2), a membrane-bound homodimeric enzyme that specifically hydroxylates lysine in the telopeptide of procollagens, and assess the clinical significance of PLOD2 in colorectal cancer (CRC). Our results showed that PLOD2 was highly expressed in CRC tumor tissues samples and cell lines both in mRNA and protein level. Next, we found that PLOD2 was positively correlated with Grade (p=0.001), T stage (p=0.001), N stage (p<0.001) and an advanced TNM stage (p<0.001). PLOD2 knockdown attenuates CRC cell proliferation, migration and invasion in vitro. Mechanism analysis PLOD2 affected glycolysis by regulating HK2 expression. HK2 reverses the inhibiting effects of PLOD2 knockdown in CRC. Furthermore, the data suggest that PLOD2 could regulate the expression of HK2 via the STAT3 signaling pathway. Survival analysis reveals that high PLOD2 (HR = 3.800, p < 0.001) and HK2 expression (HR = 10.222, p < 0.001) were correlated with overall survival. After analyzing their expression and correlation, PLOD2 was positively correlated with HK2 (r=0.590, p < 0.001). Our findings have uncovered that PLOD2 is a novel regulatory factor of glucose metabolism via controlling HK2 expression in CRC cells, suggesting PLOD2 as a promising therapeutic target for CRC treatment.

19.
Brain Behav ; : e01477, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31749292

RESUMO

BACKGROUND: This study aims to analyze the clinical, imaging, electrophysiological, and dermatopathological features of a patient with adult-onset neuronal intranuclear inclusion disease (NIID) and to explore the diagnostic methods of adult-onset NIID. CASE PRESENTATION: We here report a 63-year-old male with recurrent acute encephalopathy syndrome and autonomic nervous system damage syndrome characterized by sexual dysfunction and urinary and fecal dysfunction. Cranial diffusion-weighted magnetic resonance imaging (DWI) demonstrated symmetrically distributed strip-shaped high-intensity signal in bilateral fronto-occipital-parietal cortical-medullary junction. Electrophysiological test revealed that the main site of injury was myelin sheath in both motor and sensory nerves. Skin biopsy revealed eosinophilic spherical inclusion bodies in the nucleus of sweat gland epithelial cells. CONCLUSION: This case suggests that adult NIID is a chronic neurodegenerative disease with high clinical heterogeneity. Subcortical strip-shaped high-intensity signal on DWI has high diagnostic significance. Eosinophilic intranuclear inclusion bodies detected by skin biopsy contribute to diagnosis.

20.
iScience ; 21: 549-561, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31715498

RESUMO

Multi-targeted kinase inhibitors, such as sorafenib, have been used in various malignancies, but their efficacy in clinical applications varies among individuals and lacks pretherapeutic prediction measures. We applied the concept of "click chemistry" to pathological staining and established a drug-loaded probe staining assay. We stained the cells and different types of pathological sections and demonstrated that the assay was reliable. We further verified in cells, cell-derived xenograft model, and clinical level that the staining intensity of the probe could reflect drug sensitivity. The stained samples from 300 patients who suffered from hepatocellular carcinoma and used the sorafenib probe also indicated that staining intensity was closely related to clinical information and could be used as an independent marker without undergoing sorafenib therapy for prognosis. This assay provided new ideas for multi-target drug clinical trials, pre-medication prediction, and pathological research.

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