Since its emergence in December 2019, corona virus disease 2019 (COVID-19) has impacted several countries, affecting more than 90 thousand patients and making it a global public threat. The routes of ...transmission are direct contact, and droplet and possible aerosol transmissions. Due to the unique nature of dentistry, most dental procedures generate significant amounts of droplets and aerosols, posing potential risks of infection transmission. Understanding the significance of aerosol transmission and its implications in dentistry can facilitate the identification and correction of negligence in daily dental practice. In addition to the standard precautions, some special precautions that should be implemented during an outbreak have been raised in this review.
The quantum-level interplay between geometry, topology and correlation is at the forefront of fundamental physics1-15. Kagome magnets are predicted to support intrinsic Chern quantum phases owing to ...their unusual lattice geometry and breaking of time-reversal symmetry14,15. However, quantum materials hosting ideal spinorbit-coupled kagome lattices with strong out-of-plane magnetization are lacking16-21. Here, using scanning tunnelling microscopy, we identify a new topological kagome magnet, TbMn6Sn6, that is close to satisfying these criteria. We visualize its effectively defect-free, purely manganese-based ferromagnetic kagome lattice with atomic resolution. Remarkably, its electronic state shows distinct Landau quantization on application of a magnetic field, and the quantized Landau fan structure features spin-polarized Dirac dispersion with a large Chern gap. We further demonstrate the bulk-boundary correspondence between the Chern gap and the topological edge state, as well as the Berry curvature field correspondence of Chern gapped Dirac fermions. Our results point to the realization of a quantum-limit Chern phase in TbMn6Sn6, and may enable the observation of topological quantum phenomena in the RMn6Sn6 (where R is a rare earth element) family with a variety of magnetic structures. Our visualization ofthe magnetic bulk-boundary-Berry correspondence covering real space and momentum space demonstrates a proof-of-principle method for revealing topological magnets.
Background
Numerous reports on microRNAs have illustrated their role in tumor growth and metastasis. Recently, a new prognostic factor, miR‐125b‐2‐3p, has been identified for predicting ...chemotherapeutic sensitivity in advanced colorectal cancer (CRC). However, the specific mechanisms and biological functions of miR‐125b‐2‐3p in advanced CRC under chemotherapy have yet to be elucidated.
Methods
MiR‐125b‐2‐3p expression was detected by real‐time PCR (RT‐PCR) in CRC tissues. The effects of miR‐125b‐2‐3p on the growth, metastasis, and drug sensitivity of CRC cells were tested in vitro and in vivo. Based on multiple databases, the upstream competitive endogenous RNAs (ceRNAs) and the downstream genes for miR‐125b‐2‐3p were predicted by bioinformatic analysis, followed by the experiments including luciferase reporter assays, western blot assays, and so on.
Results
MiR‐125b‐2‐3p was significantly lowly expressed in the tissues and cell lines of CRC. Higher expression of miR‐125b‐2‐3p was associated with relatively lower proliferation rates and fewer metastases. Moreover, overexpressed miR‐125b‐2‐3p remarkably improved chemotherapeutic sensitivity of CRC in vivo and in vitro. Mechanistically, miR‐125b‐2‐3p was absorbed by long noncoding RNA (lncRNA) XIST regulating WEE1 G2 checkpoint kinase (WEE1) expression. The upregulation of miR‐125b‐2‐3p inhibited the proliferation and epithelial‐mesenchymal transition (EMT) of CRC induced by lncRNA XIST.
Conclusions
Lower miR‐125b‐2‐3p expression resulted in lower sensitivity of CRC to chemotherapy and was correlated with poorer survival of CRC patients. LncRNA XIST promoted CRC metastasis acting as a ceRNA for miR‐125b‐2‐3p to mediate WEE1 expression. LncRNA XIST‐miR‐125b‐2‐3p‐WEE1 axis not only regulated CRC growth and metastasis but also contributed to chemotherapeutic resistance to CRC.
Low expression of miR‐125b‐2‐3p in CRC was linked to lower chemotherapeutic sensitivity and poor survival. The lncRNA XIST promoted CRC invasion and migration by functioning as a ceRNA for miR‐125b‐2‐3p to mediate WEE1 expression. Our findings suggest that the lncRNA XIST‐miR‐125b‐2‐3p‐WEE1 axis not only regulated CRC growth and metastasis but also contributed to chemotherapeutic resistance to CRC, which may shed light on their targeted applications.
Non‐aqueous solvents, in particular N,N‐dimethylaniline (NMP), are widely applied for electrode fabrication since most sodium layered oxide cathode materials are readily damaged by water molecules. ...However, the expensive price and poisonousness of NMP unquestionably increase the cost of preparation and post‐processing. Therefore, developing an intrinsically stable cathode material that can implement the water‐soluble binder to fabricate an electrode is urgent. Herein, a stable nanosheet‐like Mn‐based cathode material is synthesized as a prototype to verify its practical applicability in sodium‐ion batteries (SIBs). The as‐prepared material displays excellent electrochemical performance and remarkable water stability, and it still maintains a satisfactory performance of 79.6% capacity retention after 500 cycles even after water treatment. The in situ X‐ray diffraction (XRD) demonstrates that the synthesized material shows an absolute solid‐solution reaction mechanism and near‐zero‐strain. Moreover, the electrochemical performance of the electrode fabricated with a water‐soluble binder shows excellent long‐cycling stability (67.9% capacity retention after 500 cycles). This work may offer new insights into the rational design of marvelous water stability cathode materials for practical SIBs.
An intrinsic stable layered oxide cathode material with absolute solid‐solution reaction, near‐zero‐strain, and marvelous water stability is designed for demonstrating the feasibility of fabricating an electrode with a water‐soluble binder. The electrode using a water‐soluble binder exhibits comparable electrochemical performance to that fabricated with an organic‐solution binder. This work will inspire the exploration of highly water‐stable sodium layered oxide cathode materials.
Direct structural information of confined CO
in a micropore is important for elucidating its specific binding or activation mechanism. However, weak gas-binding ability and/or poor sample ...crystallinity after guest exchange hindered the development of efficient materials for CO
incorporation, activation and conversion. Here, we present a dynamic porous coordination polymer (PCP) material with local flexibility, in which the propeller-like ligands rotate to permit CO
trapping. This process can be characterized by X-ray structural analysis. Owing to its high affinity towards CO
and the confinement effect, the PCP exhibits high catalytic activity, rapid transformation dynamics, even high size selectivity to different substrates. Together with an excellent stability with turnover numbers (TON) of up to 39,000 per Zn
cluster of catalyst after 10 cycles for CO
cycloaddition to form value-added cyclic carbonates, these results demonstrate that such distinctive structure is responsible for visual CO
capture and size-selective conversion.
Amplification of chromosome 7q21-7q31 is associated with tumor recurrence and multidrug resistance, and several genes in this region are powerful drivers of hepatocellular carcinoma (HCC). We aimed ...to investigate the key circular RNAs (circRNAs) in this region that regulate the initiation and development of HCC.
We used qRT-PCR to assess the expression of 43 putative circRNAs in this chromosomal region in human HCC and matched nontumor tissues. In addition, we used cultured HCC cells to modify circRNA expression and assessed the effects in several cell-based assays as well as gene expression analyses via RNA-seq. Modified cells were implanted into immunocompetent mice to assess the effects on tumor development. We performed additional experiments to determine the mechanism of action of these effects.
circMET (hsa_circ_0082002) was overexpressed in HCC tumors, and circMET expression was associated with survival and recurrence in HCC patients. By modifying the expression of circMET in HCC cells in vitro, we found that circMET overexpression promoted HCC development by inducing an epithelial to mesenchymal transition and enhancing the immunosuppressive tumor microenvironment. Mechanistically, circMET induced this microenvironment through the miR-30-5p/Snail/ dipeptidyl peptidase 4(DPP4)/CXCL10 axis. In addition, the combination of the DPP4 inhibitor sitagliptin and anti-PD1 antibody improved antitumor immunity in immunocompetent mice. Clinically, HCC tissues from diabetic patients receiving sitagliptin showed higher CD8
T cell infiltration than those from HCC patients with diabetes without sitagliptin treatment.
circMET is an onco-circRNA that induces HCC development and immune tolerance via the Snail/DPP4/CXCL10 axis. Furthermore, sitagliptin may enhance the efficacy of anti-PD1 therapy in a subgroup of patients with HCC.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Polyoxometalates (POMs) are a series of molecular metal oxide clusters, which span the two domains of solutes and solid metal oxides. The unique characters of POMs in structure, geometry, and ...adjustable redox properties have attracted widespread attention in functional material synthesis, catalysis, electronic devices, and electrochemical energy storage and conversion. This review is focused on the links between the intrinsic charge carrier behaviors of POMs from a chemistry‐oriented view and their recent ground‐breaking developments in related areas. First, the advantageous charge transfer behaviors of POMs in molecular‐level electronic devices are summarized. Solar‐driven, thermal‐driven, and electrochemical‐driven charge carrier behaviors of POMs in energy generation, conversion and storage systems are also discussed. Finally, present challenges and fundamental insights are discussed as to the advanced design of functional systems based upon POM building blocks for their possible emerging application areas.
The links between the intrinsic charge‐carrier behaviors of polyoxometalates (POMs) from a chemistry‐oriented view are discussed and their recent ground‐breaking developments in related areas, including molecular‐level electronic devices, solar‐driven, thermally driven, and electrochemically driven energy generation, conversion, and storage systems are reviewed. Finally, present challenges and the fundamental insights for advanced design and self‐assembly of POM building blocks are also discussed.
Recently, the dysregulation of circular RNA (circRNA) have been shown to have important regulatory roles in cancer development and progression, including hepatocellular carcinoma (HCC). However, the ...roles of most circRNAs in HCC are still unknown.
The expression of circular tripartite motif containing 33-12 (circTRIM33-12) in HCC tissues and cell lines was detected by qRT-PCR. The role of circTRIM33-12 in HCC progression was assessed by western blotting, CCK-8, flow cytometry, transwell and a subcutaneous tumor mouse assays both in vitro and in vivo. In vivo circRNA precipitation, RNA immunoprecipitation, luciferase reporter assays were performed to evaluate the interaction between circTRIM33-12 and miR-191.
Here, we found that circTRIM33-12, is downregulated in HCC tissues and cell lines. The downregulation of circTRIM33-12 in HCC was significantly correlated with malignant characteristics and served as an independent risk factor for the overall survival (OS) and recurrence-free survival (RFS) of patients with HCC after surgery. The reduced expression of circTRIM33-12 in HCC cells increases tumor proliferation, migration, invasion and immune evasion. Mechanistically, we demonstrated that circTRIM33-12 upregulated TET1 expression by sponging miR-191, resulting in significantly reduced 5-hydroxymethylcytosine (5hmC) levels in HCC cells.
These results reveal the important role of circTRIM33-12 in the proliferation, migration, invasion and immune evasion abilities of HCC cells and provide a new perspective on circRNAs in HCC progression.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
High‐performance photonic nonvolatile memory combining photosensing and data storage with low power consumption ensures the energy efficiency of computer systems. This study first reports in situ ...derived phosphorene/ZnO hybrid heterojunction nanoparticles and their application in broadband‐response photonic nonvolatile memory. The photonic nonvolatile memory consistently exhibits broadband response from ultraviolet (380 nm) to near infrared (785 nm), with controllable shifts of the SET voltage. The broadband resistive switching is attributed to the enhanced photon harvesting, a fast exciton separation, as well as the formation of an oxygen vacancy filament in the nano‐heterojunction. In addition, the device exhibits an excellent stability under air exposure compared with reported pristine phosphorene‐based nonvolatile memory. The superior antioxidation capacity is believed to originate from the fast transfer of lone‐pair electrons of phosphorene. The unique assembly of phosphorene/ZnO nano‐heterojunctions paves the way toward multifunctional broadband‐response data‐storage techniques.
A solution‐processed phosphorene/ZnO nano‐heterojunction is demonstrated. Light‐tunable broadband resistive switching from UV to NIR is realized through the novel optoelectronic coupling of ZnO and phosphorene in resistive random access memory (RRAM). Superior environmental tolerance together with a synergetic photovoltaic and photogating effect paves the way of this attractive material for next‐generation photonic RRAM devices.
Copper‐catalyzed silylarylation of N‐(arylsulfonyl)acrylamides via a tandem silyl radical addition/1,4‐aryl migration/desulfonylation sequence has been developed. This method employs silanes as the ...precursor of silyl radical and di‐tert‐butyl peroxide (DTBP) as the initiator. By using this cascade procedure, a series of β‐silyl amide‐pharmaceutical hybrids which contain an α‐all‐carbon quaternary stereocenter were facilely synthesized.
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