Two-dimensional materials provide extraordinary opportunities for exploring phenomena arising in atomically thin crystals. Beginning with the first isolation of graphene, mechanical exfoliation has ...been a key to provide high-quality two-dimensional materials, but despite improvements it is still limited in yield, lateral size and contamination. Here we introduce a contamination-free, one-step and universal Au-assisted mechanical exfoliation method and demonstrate its effectiveness by isolating 40 types of single-crystalline monolayers, including elemental two-dimensional crystals, metal-dichalcogenides, magnets and superconductors. Most of them are of millimeter-size and high-quality, as shown by transfer-free measurements of electron microscopy, photo spectroscopies and electrical transport. Large suspended two-dimensional crystals and heterojunctions were also prepared with high-yield. Enhanced adhesion between the crystals and the substrates enables such efficient exfoliation, for which we identify a gold-assisted exfoliation method that underpins a universal route for producing large-area monolayers and thus supports studies of fundamental properties and potential application of two-dimensional materials.
The changes in olfactory bulb (OB) volume in Parkinson's disease (PD) patients have not yet been comprehensively evaluated. The purpose of this meta-analysis was to explore whether the OB volume was ...significantly different between PD patients and healthy controls.
PubMed and Embase were searched up to March 6, 2015 with no language restrictions. Two independent reviewers screened eligible studies and extracted data on study characteristics and OB volume. Additionally, a systematic review and meta-analysis using a random-effects model were conducted. Publication bias was determined by using funnel plots and Begg's and Egger's tests. Subgroup analyses were performed to assess possible sources of heterogeneity.
Six original case-control studies of 216 PD patients and 175 healthy controls were analyzed. The pooled weighted mean difference (WMD) in the OB volume between the PD patients and the healthy participants was -8.071 for the right OB and -10.124 for the left OB; these values indicated a significant difference among PD patients compared with healthy controls. In addition, a significant difference in the lateralized OB volume was observed in PD patients, with a pooled WMD of 1.618; these results indicated a larger right OB volume than left OB volume in PD patients. In contrast, no difference in the lateralized OB volume was found in healthy controls. No statistical evidence of publication bias among studies was found based on Egger's or Begg's tests. Sensitivity analyses revealed that the results were consistent and robust.
Overall, both the left and the right OB volume were significantly smaller in PD patients than in healthy controls. However, significant heterogeneity and an insufficient number of studies underscore the need for further observational research.
Objective- Vascular adventitia encompasses progenitors and is getting recognized as the major site of inflammation in early stage of atherosclerosis. However, the cellular atlas of the heterogeneous ...adventitial cells, the intercellular communication, the cellular response of adventitia to hyperlipidemia, and its contribution to atherosclerosis have been elusive. Approach and Results- Single-cell RNA sequencing was applied to wt (wild type) and ApoE (apolipoprotein E)-deficient aortic adventitia from 12-week-old C57BL/6J mice fed on normal laboratory diet with early stage of atherosclerosis. Unbiased clustering analysis revealed that the landscape of adventitial cells encompassed adventitial mesenchyme cells, immune cells (macrophages, T cells, and B cells), and some types of rare cells, for example, neuron, lymphatic endothelial cells, and innate lymphoid cells. Seurat clustering analysis singled out 6 nonimmune clusters with distinct transcriptomic profiles, in which there predominantly were stem/progenitor cell-like and proinflammatory population (Mesen II). In ApoE-deficient adventitia, resident macrophages were activated and related to increased myeloid cell infiltration in the adventitia. Cell communication analysis further elucidated enhanced interaction between a mesenchyme cluster and inflammatory macrophages in ApoE-deficient adventitia. In vitro transwell assay confirmed the proinflammatory role of SCA1
(stem cell antigen 1 positive) Mesen II population with increased CCL2 (chemokine C-C motif ligand 2) secretion and thus increased capacity to attract immune cells in ApoE-deficient adventitia. Conclusions- Cell atlas defined by single-cell RNA sequencing depicted the heterogeneous cellular landscape of the adventitia and uncovered several types of cell populations. Furthermore, resident cell interaction with immune cells appears crucial at the early stage of atherosclerosis.
Endothelial dysfunction is critically involved in the pathogenesis of pulmonary arterial hypertension (PAH) and that exogenously administered microRNA may be of therapeutic benefit. Lower levels of ...miR‐483 were found in serum from patients with idiopathic pulmonary arterial hypertension (IPAH), particularly those with more severe disease. RNA‐seq and bioinformatics analyses showed that miR‐483 targets several PAH‐related genes, including transforming growth factor‐β (TGF‐β), TGF‐β receptor 2 (TGFBR2), β‐catenin, connective tissue growth factor (CTGF), interleukin‐1β (IL‐1β), and endothelin‐1 (ET‐1). Overexpression of miR‐483 in ECs inhibited inflammatory and fibrogenic responses, revealed by the decreased expression of TGF‐β, TGFBR2, β‐catenin, CTGF, IL‐1β, and ET‐1. In contrast, inhibition of miR‐483 increased these genes in ECs. Rats with EC‐specific miR‐483 overexpression exhibited ameliorated pulmonary hypertension (PH) and reduced right ventricular hypertrophy on challenge with monocrotaline (MCT) or Sugen + hypoxia. A reversal effect was observed in rats that received MCT with inhaled lentivirus overexpressing miR‐483. These results indicate that PAH is associated with a reduced level of miR‐483 and that miR‐483 might reduce experimental PH by inhibition of multiple adverse responses.
Synopsis
This study reveals a protective role for miR‐483 in the development of pulmonary arterial hypertension (PAH). Overexpression of miR‐483 in endothelial cells (ECs) inhibits inflammatory and fibrogenic responses and leads to ameliorated pulmonary hypertension phenotypes in rats.
Lower levels of miR‐483 were found in the serum from patients with idiopathic pulmonary arterial hypertension, particularly in those with more severe disease.
MiR‐483 targets multiple genes that are involved in the pathogenesis of PAH.
Overexpression of miR‐483 in ECs inhibited inflammatory and fibrogenic responses.
Intratracheal administration or EC‐specific overexpression of miR‐483 alleviated pulmonary hypertension in rats.
This study reveals a protective role for miR‐483 in the development of pulmonary arterial hypertension (PAH). Overexpression of miR‐483 in endothelial cells (ECs) inhibits inflammatory and fibrogenic responses and leads to ameliorated pulmonary hypertension phenotypes in rats.
Abstract
The nuclear factor kappa B (NF-κB) pathway and inhibitor of NF-κB kinase β (IKKβ) are involved in Alzheimer disease (AD) pathogenesis. This study explored the mechanisms underlying ...IKKβ-mediated Aβ aggregation and neuron regeneration in APP.PS1 mice. Adenoviral transduction particles were injected into the hippocampal CA1 region of the mice to knock down or inhibit target genes. Morris water maze was performed to evaluate the cognitive function of the mice. Aβ deposition was determined by histological examination. sh-IKKβ plasmids and microRNA (miR)-155-5p inhibitor were transfected into Aβ1-42-induced N2a cells. The expressions of AD-related proteins were detected by Western blot. The interaction between S-phase kinase-associated protein 2 (SKP2) and IKKβ was assessed by co-immunoprecipitation. IKKβ knockdown (KD) and miR-155-5p inhibition ameliorated cognitive impairment, improved neuron regeneration, and attenuated Aβ deposition in APP/PS1 mice. SKP2 KD aggravated cognitive impairment, inhibited neuron regeneration, and promoted Aβ deposition in the mice. SKP2 regulated the stability of IKKβ protein via ubiquitination. MiR-155-5p regulates Aβ deposition and the expression of Aβ generation-related proteins in N2a cells via targeting SKP2. These results indicate that the miR-155-5p/SKP2/IKKβ axis was critical for pathogenesis in this AD model and suggest the potential of miR-155-5p as a target for AD treatment.
Allylation and propargylation are two powerful synthetic strategies for making new substances that have been of significant importance in chemistry, medicine, and material fields. Conventional ...tactics employ various preformed allylation and propargylation reagents. In this study, a conceptually novel copper-catalyzed and B2pin2-mediated Umpolung reactivity of propargylic carbonates has been achieved for the first time, realizing both allylation and propargylation of aldehydes and ketones without additional reductants. Three types of allylation products and one type of propargylation product are generated efficiently, and all allylation products are formed with syn-configurations predominantly. The choice of ligands plays a vital role in modulating the Umpolung modes. The synthetic applications have been demonstrated in a myriad of further transformations including natural product synthesis, and systematic mechanistic studies have been conducted to reveal detailed insights into the Umpolung processes.
The popularity and flexibility of the Android platform makes it the primary target of malicious attackers. The behaviors of malware, such as malicious charges and privacy theft, pose serious security ...threats to users. Permission granting, as the primary security scheme of Android, is a prerequisite for performing dangerous operations on devices by invoking Application Programming Interfaces (APIs). Besides, permission and hardware features are jointly declared in the manifest file of an application (app) to guarantee its device compatibility. Thus, we extract permissions, API calls and hardware features to characterize apps. Furthermore, we design a novel architectural unit, Multi-Head Squeeze-and-Excitation Residual block (MSer), to learn the intrinsic correlation between features and recalibrating them from multiple perspectives. Based on these two works, we propose a new malware detection framework MSerNetDroid. To investigate the effectiveness of the proposed framework, we analyzed 2,126 malicious apps and 1,061 benign ones collected from VirusShare and Google Play Store. The assessment results demonstrate that the proposed model successful detects malware with an accuracy of 96.48%. We also compare the proposed method with the state-of-the-art approaches, including the use of diversity static features and various detection algorithms. These promising experimental results consistently show that MSerNetDroid is an effective way to detect Android malware.
NUT midline carcinoma (NMC), a rare type of squamous cell carcinoma, is genetically characterised by NUT midline carcinoma family member 1 (NUTM1) gene rearrangement. NMC can arise from the lungs; ...however, there is no standard for the management of primary pulmonary NMC. This study aimed to confirm the clinical features and report the treatments, especially with immune checkpoint inhibitors (ICIs), and outcomes of patients with primary pulmonary NMC. A retrospective review of patients with primary pulmonary NMC was performed in the First Affiliated Hospital of Guangzhou Medical University between January 2015 and December 2018. Clinical manifestations as well as radiographic and pathological findings were recorded. Whole-exome sequencing (WES), a predictor for ICI response, was used to determine the tumour mutational burden (TMB). Treatments, especially by immune checkpoint blockade, and patient survival were analysed. Seven patients with primary pulmonary mass (four men and three women) with a mean age of 42 years (range, 23-74) who were diagnosed with NMC according to NUT immunohistochemistry staining were included for analysis. One patient had a rare fusion of CHRM5-NUTM1 by tumour sequencing. A wide range of TMB (1.75-73.81 mutations/Mbp) was observed. The initial treatments included chemotherapy (5/7, 71.4%), surgery (1/7, 14.3%), and radiotherapy (1/7, 14.3%). Five patients (5/7, 71.4%) received ICIs (programmed cell death protein 1 PD1/programmed cell death ligand 1 PDL1 monoclonal antibody) as second- or higher-line treatments. The median overall survival (OS) was 4.1 months (range, 1.5-26.7 months).
The strong Brønsted basic character of N‐heterocyclic carbenes (NHCs) has been used to promote the cascade double Michael addition between fluorenes and dienones. Under catalyst loadings of 1–5 mol% ...of NHC, fluorene reacts with divinyl ketones (DVKs) to afford anti‐spirofluorene compounds in high yields. However, when benzenedi(enones) were employed as Michael acceptors in the presence of 10 mol% of NHC, fluorene undergoes a different inter‐ and intramolecular cascade double Michael addition, providing multi‐substituted indanes in high yields with excellent diastereoselectivity.
Diverse functionalized thioethers were efficiently synthesized through the multicomponent reaction of benzynes, cyclic thioethers and different nucleophiles. Both inorganic salts (KF, KCl, KBr, and ...KSCN) and silylated reagents (TMSCN, TMSN3, TMSCl) can be utilized as efficient nucleophiles for the reaction.
Benzyne-induced synthesis of diverse functionalized thioethers. Display omitted
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