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1.
Nat Commun ; 11(1): 5613, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154384

RESUMO

The kagome lattice Co3Sn2S2 exhibits the quintessential topological phenomena of a magnetic Weyl semimetal such as the chiral anomaly and Fermi-arc surface states. Probing its magnetic properties is crucial for understanding this correlated topological state. Here, using spin-polarized scanning tunneling microscopy/spectroscopy (STM/S) and non-contact atomic force microscopy (nc-AFM) combined with first-principle calculations, we report the discovery of localized spin-orbit polarons (SOPs) with three-fold rotation symmetry nucleated around single S-vacancies in Co3Sn2S2. The SOPs carry a magnetic moment and a large diamagnetic orbital magnetization of a possible topological origin associated relating to the diamagnetic circulating current around the S-vacancy. Appreciable magneto-elastic coupling of the SOP is detected by nc-AFM and STM. Our findings suggest that the SOPs can enhance magnetism and more robust time-reversal-symmetry-breaking topological phenomena. Controlled engineering of the SOPs may pave the way toward practical applications in functional quantum devices.

2.
Front Chem ; 8: 552795, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195046

RESUMO

Exploration of high-efficiency and inexpensive electrode catalysts is of vital importance for the hydrogen evolution reaction (HER). In this research, an amorphous Co-Al-P layer was constructed on the surface of CoAl layered double hydroxide (CoAl-LDH) via an in-situ wet phosphidation strategy. The core-shell CoAl-LDH@Co-Al-P on Ti mesh (CoAl-LDH@Co-Al-P/TM) as an active HER electrocatalyst demands an overpotential of 150 mV to achieve a current density of 10 mA cm-2 at neutral pH. Moreover, CoAl-LDH@Co-Al-P/TM also exhibits good electrochemical stability and a superior Faradic efficiency of nearly 100%.

3.
Aging (Albany NY) ; 12(22): 23233-23250, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33221742

RESUMO

Nuclear paraspeckles assembly transcript 1 (NEAT1) is a well-known long noncoding RNA (lncRNA) with various functions in different physiological and pathological processes. Notably, aberrant NEAT1 expression is implicated in the pathogenesis of various neurodegenerative diseases, including Alzheimer's disease (AD). However, the molecular mechanism of NEAT1 in AD remains poorly understood. In this study, we investigated that NEAT1 regulated microtubules (MTs) polymerization via FZD3/GSK3ß/p-tau pathway. Downregulation of NEAT1 inhibited Frizzled Class Receptor 3 (FZD3) transcription activity by suppressing H3K27 acetylation (H3K27Ac) at the FZD3 promoter. Our data also demonstrated that P300, an important histone acetyltransferases (HAT), recruited by NEAT1 to bind to FZD3 promoter and mediated its transcription via regulating histone acetylation. In addition, according to immunofluorescence staining of MTs, metformin, a medicine for the treatment of diabetes mellitus, rescued the reduced length of neurites detected in NEAT1 silencing cells. We suspected that metformin may play a neuroprotective role in early AD by increasing NEAT1 expression and through FZD3/GSK3ß/p-tau pathway. Collectively, NEAT1 regulates microtubule stabilization via FZD3/GSK3ß/P-tau pathway and influences FZD3 transcription activity in the epigenetic way.

4.
Surg Endosc ; 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33237468

RESUMO

BACKGROUND: Robotic colorectal cancer surgery is widely accepted and applied. However, there is still no objective and comprehensive assessment on the data of nationwide multicenter series. METHOD: A total of 28 medical centers in Mainland China participated in this nationwide retrospective observational study. From the first case performed in each center to the last until December 2017, patients with robotic resection for primary tumor and pathologically confirmed colorectal adenocarcinoma were consecutively enrolled. Clinical, pathological and follow-up data were collected and analyzed. RESULTS: A total of 5389 eligible patients were finally enrolled in this study, composing 72.2% of the total robotic colorectal surgery volume of Mainland China in the same period. For resections of one bowel segment of primary tumor, the postoperative mortality rate was 0.08% (4/5063 cases), and the postoperative complication rate (Clavien-Dindo grade II or higher) was 8.6% (434/5063 cases). For multiple resections, the postoperative mortality rate was 0.6% (2/326 cases), and the postoperative complication rate was 16.3% (53/326 cases). Out of 2956 patients receiving sphincter-preserving surgery in only primary resection, 130 (4.4%) patients had anastomotic leakage. Traditional low anterior resection (tumor at middle rectum) (OR 2.384, P < 0.001), traditional low anterior resection (tumor at low rectum) (OR 1.968, P = 0.017) and intersphincteric resection (OR 5.468, P = 0.006) were significant independent risk factors for anastomotic leakage. Female gender (OR 0.557, P = 0.005), age ≥ 60 years (OR 0.684, P = 0.040), and preventive stoma (OR 0.496, P = 0.043) were significant independent protective factors. Body mass index, preoperative chemotherapy/radiotherapy, tumor size, and TNM stage did not independently affect the occurrence of anastomotic leakage. CONCLUSION: Robotic colorectal cancer surgery was safe and reliable and might have advantages in patients at high risk of anastomotic leakage.

5.
Front Oncol ; 10: 567042, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33123477

RESUMO

Differential expressions and functions of various micoRNAs (miRNAs) have been intensively studied in both colon and rectal cancers. However, the importance of miRNAs on radiotherapy (RT) response and clinical outcome in rectal cancer patients remains unclear. In this study, we used real-time polymerase chain reaction to examine the expressions of miR-302a, miR-105, and miR-888 in normal mucosa and cancer tissue from rectal cancer patients with and without preoperative RT. The biological function of miR-302a, miR-105, and miR-888 expression was further analyzed and identified through the public databases: TCGA (The Cancer Genome Atlas) and GEPIA (Gene Expression Profiling Interactive Analysis). The results showed that the expression of miR-105 in rectal cancer was higher than that in normal mucosa in RT (P = 0.042) and non-RT patients (P = 0.003) and was associated with mucinous histological type (P = 0.004), COX-2 (P = 0.042), and p73 expression (P = 0.030). The expression of miR-302a was shown more frequently in cancers with necrosis (P = 0.033) and with WRAP53 expression (P = 0.015), whereas miR-888 expression occurred more frequently in tumors with protein the expression of survivin (P = 0.015), AEG-1 (astrocyte elevated gene-1) (P = 0.003), and SATB1 (special AT-rich sequence binding protein 1) (P = 0.036). Moreover, TargetScan also predicted AEG-1 and SATB1 as putative targets for miR-888. The miRNA-gene network analysis showed that ABI2 was associated with all the three miRNAs, with lower expression and good diagnostic value in rectal cancers. The TCGA database demonstrated the association of miR-105 expression with high carcinoembryonic antigen level (P = 0.048). RT reduced the expressions of miR-302a, miR-105, and miR-888. Prognostic analysis showed that miR-888 expression was independently associated with worse survival of patients without RT [overall survival, P = 0.001; disease-free survival, P = 0.009]. Analysis of biological function revealed that the protein serine/threonine kinase activity and PI3K-AKT signaling pathway were the most significantly enriched functions and pathways, respectively. Our findings suggest that miR-105 is involved in rectal cancer pathogenesis and miR-888 is associated with prognosis. MiR-302a, miR-105, and miR-888 have potential influence on the pathogenesis, RT, and prognosis of rectal cancer.

6.
Chem Commun (Camb) ; 56(88): 13595-13598, 2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33057514

RESUMO

Herein, a two-step method is proposed to synthesize bunched RhTe nanochains (RhTe NCs) using Te nanowires and formic acid both as a reductant and a structure-directing agent. The resultant RhTe NCs possess a high electrochemical active surface area of 89.3 m2 gRh-1, and exhibit superior catalytic activity and durability towards the electro-oxidation of methanol in an alkaline medium.

8.
Cancer Lett ; 493: 228-235, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-32898600

RESUMO

Colorectal cancer (CRC) is a commonly diagnosed malignancy with unsatisfactory survival outcomes. Recent studies indicate that noncoding RNAs (ncRNAs) can be selectively packaged into exosomes, the extracellular vesicles composed of a lipid bilayer, and delivered from donor to recipient cells, thus regulating the behavior of the recipient cells. Increasing evidence has demonstrated that exosomal ncRNAs in blood exhibit distinct expression patterns among CRC patients with or without metastasis, and healthy controls. Moreover, exosomal ncRNAs can participate in the regulation of tumor microenvironment, the establishment of pre-metastatic niches, and the induction of drug resistance via cell-to-cell communication. Intriguingly, exosomal ncRNAs have the potential to serve as biomarkers for diagnosis, prognostic prediction, and therapeutic response monitoring of patients with CRC. In this review, we summarize the emerging functions of exosomal ncRNAs during CRC development and also discuss their potential clinical application in patients with CRC.

9.
J Biomed Nanotechnol ; 16(5): 672-688, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919487

RESUMO

The lack of neo-cartilage integration with host tissues is a great challenge for the clinical translation of new technologies for the repair of articular cartilage (AC) defect. Recently, we developed a promising double-layered collagen-based system for targeted delivery of fibroblast growth factor 2 (FGF2) to the subchondral bone for AC repair. The system effectively promoted the regeneration of both cartilage and subchondral bone. However, neo-cartilage integration was unsatisfactory, which might be due to the presence of a zone of cell death (ZCD) in the cartilage induced by injury. Here, we hypothesized that maintaining cell viability in the region surrounding the defect and decreasing the size of ZCD by using chondroprotective agents such as insulin-like growth factor-1 (IGF-1), might be an effective strategy to improve neo-cartilage integration. A targeted delivery system for IGF-1 to cartilage based on the FGF2 delivery system was formulated to weaken the impact on the effects of FGF2. The two growth factors were incorporated into the different layers of the membrane without interdiffusion. Due to the different densities of collagen fibers in the different layers, the in vitro and in vivo assays demonstrated that both proteins were released via unidirectional diffusion without mixing or lateral diffusion. Particularly, the released IGF-1 increased the viability of chondrocytes, decreased the ZCD size, and enhanced the integration of regenerative neo-cartilage with host tissues, without any undesirable effects on the FGF2mediated regeneration of cartilage and subchondral bone. Taken together, our findings demonstrate that the collagen fiber membrane-aided chondroprotective-based strategy is an effective way to improve neo-cartilage integration.


Assuntos
Cartilagem Articular , Osso e Ossos , Condrócitos , Colágeno , Matriz Extracelular
10.
Ecotoxicol Environ Saf ; 203: 111021, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888607

RESUMO

Volatile iodine released from nuclear power plant reactors is radiological hazard to environment and human's health because of their high fission yield and environmental mobility. The complexity of nuclear waste management motivated the development of solid-phase adsorbents. Herein, co-radiation induced graft polymerization (CRIGP) was employed in the graft polymerization of N-vinyl-2-pyrrolidone (NVP) onto polyethylene-coated polypropylene skin-core (PE/PP) fibers using electron beam (EB) irradiation. This work provides a one-step green synthetic approach to prepare iodine fibrous adsorbents without any chemical initiators or large amount of organic solvent. The original and modified PE/PP fibers were characterized by fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric (TG) and scanning electron microscopy (SEM) to demonstrate the grafting of NVP onto the PE/PP fibers. The capacity of iodine absorbed by the PE/PP-g-PNVP fibers was 1237.8 mg/g after 180 min. Meanwhile, absorbents can be regenerated efficiently by two different means of ethanol elution and heating at 120 °C, respectively. Within 10 min, 94.17% and 90.12% of the iodine can be released from the PE/PP-g-PNVP fibers with these two methods, respectively. The adsorbent exhibited a long service life of at least ten adsorption-desorption cycles, suggesting that PE/PP-g-PNVP fibers might be a promising adsorbent for volatile iodine adsorption from fission products in nuclear power plant reactors.


Assuntos
Poluentes Radioativos do Ar/análise , Raios gama , Química Verde/métodos , Iodo/análise , Polipropilenos/química , Pirrolidinonas/química , Adsorção , Humanos , Cinética , Polimerização , Polipropilenos/efeitos da radiação , Pirrolidinonas/efeitos da radiação , Propriedades de Superfície
11.
Surg Innov ; : 1553350620954581, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32873180

RESUMO

Liver surgery has entered the era of precision surgery. Therefore, how to optimize the resection of lesions and reduce the unnecessary time of liver ischemia and hypoxia have become the focus. A total of 11 patients who underwent fluorescence laparoscopic liver mass resection and preoperative three-dimensional (3D) reconstruction between August 2018 and July 2020 were evaluated. Liver cirrhosis occurred in 3 patients. The mean intraoperative blood loss was 166.8 ± 105.7 mL. The average length of the operation time was 152.0 ± 45.3 minutes. The average intraoperative hilar occlusion time was 9.3 minutes (except for hilar cholangiocarcinoma). The liver function of all patients, except patients with hilar bile duct carcinoma, returned to the preoperative level at 72 hours, and no serious complications occurred. 3D reconstruction combined with fluorescence laparoscopic imaging is safe and effective for precision liver resection.

12.
Nat Commun ; 11(1): 4415, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887890

RESUMO

Quantum states induced by single-atomic impurities are at the frontier of physics and material science. While such states have been reported in high-temperature superconductors and dilute magnetic semiconductors, they are unexplored in topological magnets which can feature spin-orbit tunability. Here we use spin-polarized scanning tunneling microscopy/spectroscopy (STM/S) to study the engineered quantum impurity in a topological magnet Co3Sn2S2. We find that each substituted In impurity introduces a striking localized bound state. Our systematic magnetization-polarized probe reveals that this bound state is spin-down polarized, in lock with a negative orbital magnetization. Moreover, the magnetic bound states of neighboring impurities interact to form quantized orbitals, exhibiting an intriguing spin-orbit splitting, analogous to the splitting of the topological fermion line. Our work collectively demonstrates the strong spin-orbit effect of the single-atomic impurity at the quantum level, suggesting that a nonmagnetic impurity can introduce spin-orbit coupled magnetic resonance in topological magnets.

13.
Nanoscale ; 12(37): 19159-19164, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32944727

RESUMO

Adjusting the morphology and composition of Pd-based materials is a promising strategy to improve their performance for the electrocatalytic formic acid oxidation reaction (FAOR). In this work, we report the preparation of B-doped PdRu nanopillar assemblies (B-PdRu NPAs) by a two-step method using NaBH4 as the boron dopant. On combining the hyper-branched structure and the multi-component synergistic effect, B-PdRu NPAs achieve a high mass activity of 1.09 mA µg-1Pd for the FAOR and retain 73.19% of the initial activity after 500 cycles, which is superior to undoped counterparts. The proposed synthesis strategy provides a simple method for the synthesis of metal-nonmetal nanomaterials with desired composition and design structure for electrocatalytic fields.

14.
Nat Commun ; 11(1): 4002, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778641

RESUMO

Layered kagome-lattice 3d transition metals are emerging as an exciting platform to explore the frustrated lattice geometry and quantum topology. However, the typical kagome electronic bands, characterized by sets of the Dirac-like band capped by a phase-destructive flat band, have not been clearly observed, and their orbital physics are even less well investigated. Here, we present close-to-textbook kagome bands with orbital differentiation physics in CoSn, which can be well described by a minimal tight-binding model with single-orbital hopping in Co kagome lattice. The capping flat bands with bandwidth less than 0.2 eV run through the whole Brillouin zone, especially the bandwidth of the flat band of out-of-plane orbitals is less than 0.02 eV along Γ-M. The energy gap induced by spin-orbit interaction at the Dirac cone of out-of-plane orbitals is much smaller than that of in-plane orbitals, suggesting orbital-selective character of the Dirac fermions.

15.
Nat Commun ; 11(1): 4003, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778651

RESUMO

Kagome-nets, appearing in electronic, photonic and cold-atom systems, host frustrated fermionic and bosonic excitations. However, it is rare to find a system to study their fermion-boson many-body interplay. Here we use state-of-the-art scanning tunneling microscopy/spectroscopy to discover unusual electronic coupling to flat-band phonons in a layered kagome paramagnet, CoSn. We image the kagome structure with unprecedented atomic resolution and observe the striking bosonic mode interacting with dispersive kagome electrons near the Fermi surface. At this mode energy, the fermionic quasi-particle dispersion exhibits a pronounced renormalization, signaling a giant coupling to bosons. Through the self-energy analysis, first-principles calculation, and a lattice vibration model, we present evidence that this mode arises from the geometrically frustrated phonon flat-band, which is the lattice bosonic analog of the kagome electron flat-band. Our findings provide the first example of kagome bosonic mode (flat-band phonon) in electronic excitations and its strong interaction with fermionic degrees of freedom in kagome-net materials.

16.
Sci Rep ; 10(1): 13492, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778744

RESUMO

To reduce the view-flipping effect and enhance the viewing resolution, the modulation characteristics of the hogel based holographic stereogram is constructed and validated. The performance of the view-flipping effect is analyzed, and the results indicate that decreasing the size of hogel is beneficial to the reduction of the view flipping, however, which will result in significant diffraction effect which can degrade the reconstruction quality. Furthermore, a diffraction-limited imaging model of the hogel based holographic stereogram is established, where both the limited aperture of the hogel and the defocused aberration of the object point are introduced, and the effective resolvable size of the reconstructed image point is simulated. The theory shows that there is an optimal hogel size existed for the certain depth of scene. Both the numerical and optical experiments are implemented, and the results are well agreed with the theoretical prediction, which demonstrates that the view-flipping reduction and reconstruction visualization enhancement for EPISM based holographic stereogram can be achieved when the proper size of hogel is utilized.

17.
ANZ J Surg ; 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32856381

RESUMO

BACKGROUND: This study aimed to explore the surgical outcomes of laparoscopic total mesorectal excision (TME) combined with en-bloc seminal vesicle resection (SVR) and partial prostate resection (PPR) for locally advanced rectal cancer (LARC) after chemoradiotherapy (CRT). METHODS: Patients receiving TME combined with en-bloc SVR and PPR for LARC after CRT from 2014 to 2019 were enrolled retrospectively. Patients' characteristics and surgical outcomes were collected and analysed. RESULTS: A total of six male patients were enrolled in this study. Among them, four patients proved to be T4b stage including three Denonvilliers fascia invasion and one seminal vesicle invasion. R0 resection was achieved in all patients. With a median follow-up time of 24 months, no local recurrence was observed. CONCLUSION: It is safe and feasible to perform laparoscopic TME combined with en-bloc SVR and PPR in selected LARC patients after neoadjuvant CRT. It can provide a safe circumferential resection margin and R0 resection. More studies are warranted to improve the diagnostic accuracy for T4b stage after CRT and avoid unnecessary extended resection.

19.
Chemistry ; 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32841440

RESUMO

Electrochemical water splitting can provide a promising avenue for sustainable hydrogen production. Highly efficient electrocatalysts toward the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are extremely important for the practical application of water splitting technology. Herein, a one-step annealing strategy is reported for the fabrication of a metal-organic framework-derived bifunctional self-supported electrocatalyst, which is composed of two-dimensional N-doped carbon-wrapped Ir-doped Ni nanoparticle composites supported on Ni foam (NiIr@N-C/NF). The resultant NiIr@N-C/NF displays excellent electrocatalytic performance in 1.0 m KOH, with low overpotentials of 32 mV at 10 mA cm-2 for the HER and 329 mV at 50 mA cm-2 for the OER. Particularly, the HER-OER bifunctional NiIr@N-C/NF needs only 1.50 V to yield 10 mA cm-2 for overall water splitting.

20.
Phys Rev Lett ; 125(4): 046401, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32794798

RESUMO

We use scanning tunneling microscopy to elucidate the atomically resolved electronic structure in the strongly correlated kagome Weyl antiferromagnet Mn_{3}Sn. In stark contrast to its broad single-particle electronic structure, we observe a pronounced resonance with a Fano line shape at the Fermi level resembling the many-body Kondo resonance. We find that this resonance does not arise from the step edges or atomic impurities but the intrinsic kagome lattice. Moreover, the resonance is robust against the perturbation of a vector magnetic field, but broadens substantially with increasing temperature, signaling strongly interacting physics. We show that this resonance can be understood as the result of geometrical frustration and strong correlation based on the kagome lattice Hubbard model. Our results point to the emergent many-body resonance behavior in a topological kagome magnet.

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