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1.
Nat Commun ; 11(1): 2429, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415067

RESUMO

Proton-linked monocarboxylate transporters (MCTs) must transport monocarboxylate efficiently to facilitate monocarboxylate efflux in glycolytically active cells, and transport monocarboxylate slowly or even shut down to maintain a physiological monocarboxylate concentration in glycolytically inactive cells. To discover how MCTs solve this fundamental aspect of intracellular monocarboxylate homeostasis in the context of multicellular organisms, we analyzed pyruvate transport activity of human monocarboxylate transporter 2 (MCT2). Here we show that MCT2 transport activity exhibits steep dependence on substrate concentration. This property allows MCTs to turn on almost like a switch, which is physiologically crucial to the operation of MCTs in the cellular context. We further determined the cryo-electron microscopy structure of the human MCT2, demonstrating that the concentration sensitivity of MCT2 arises from the strong inter-subunit cooperativity of the MCT2 dimer during transport. These data establish definitively a clear example of evolutionary optimization of protein function.

3.
J Cell Mol Med ; 24(10): 5615-5628, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32243691

RESUMO

Fibroblast-myofibroblast transdifferentiation (FMT) is widely recognized as the major pathological feature of renal fibrosis. Although melatonin has exerted antifibrogenic activity in many diseases, its role in renal FMT remains unclear. In the present study, the aim was to explore the effect of melatonin on renal FMT and the underlying mechanisms. We established the transforming growth factor (TGF)-ß1 stimulated rat renal fibroblast cells (NRK-49F) model in vitro and unilateral ureteral obstruction (UUO) mice model in vivo. We assessed levels of α-smooth muscle actin (α-SMA), col1a1 and fibronectin, STAT3 and AP-1, as well as miR-21-5p and its target genes (Spry1, PTEN, Smurf2 and PDCD4). We found that melatonin reduced the expression of α-SMA, col1a1 and fibronectin, as well as the formation of α-SMA filament in TGF-ß1-treated NRK-49F cells. Meanwhile, melatonin inhibited STAT3 phosphorylation, down-regulated miR-21-5p expression, and up-regulated Spry1 and PTEN expression. Moreover, miR-21-5p mimics partially antagonized the anti-fibrotic effect of melatonin. For animal experiments, the results revealed that melatonin remarkably ameliorated UUO-induced renal fibrosis, attenuated the expression of miR-21-5p and pro-fibrotic proteins and elevated Spry1 and PTEN expression. Nevertheless, agomir of miR-21-5p blocked the renoprotective effect of melatonin in UUO mice. These results indicated that melatonin could alleviate TGF-ß1-induced renal FMT and UUO-induced renal fibrosis through down-regulation of miR-21-5p. Regulation of miR-21-5p/PTEN and/or miR-21-5p/Spry1 signal might be involved in the anti-fibrotic effect of melatonin in the kidneys of UUO mice.

4.
EMBO Mol Med ; 12(5): e11845, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32310340

RESUMO

The transcription factors of the MYC family play pivotal roles in the initiation and progression of human cancers. High oncogenic level of MYC invades low-affinity sites and enhancer sequences, which subsequently alters the transcriptome, causes metabolic imbalance, and induces stress response. The endoplasmic reticulum (ER) not only plays a central role in maintaining proteostasis, but also contributes to other key biological processes, including Ca2+ metabolism and the synthesis of lipids and glucose. Stress conditions, such as shortage in glucose or oxygen and disruption of Ca2+ homeostasis, may perturb proteostasis and induce the unfolded protein response (UPR), which either restores homeostasis or triggers cell death. Crucial roles of ER stress and UPR signaling have been implicated in various cancers, from oncogenesis to treatment response. Here, we summarize the current knowledge on the interaction between MYC and UPR signaling, and its contribution to cancer development. We also discuss the potential of targeting key UPR signaling nodes as novel synthetic lethal strategies in MYC-driven cancers.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32196447

RESUMO

AIMS: The purpose of this study was to investigate the influences of apigenin on proliferation, differentiation and function of renal fibroblast after TGF-ß1 stimulation and to uncover the underlying mechanisms. BACKGROUND: Renal fibrosis is a common pathway leading to the progression of chronic kidney disease. Activated fibroblasts contribute remarkably to the development of renal fibrosis. Although apigenin has been demonstrated to play a protective role from fibrotic diseases, its pharmacological effect on renal fibroblast activation remains largely unknown. OBJECTIVE: Here, we examined the functional role of apigenin in the activation of renal fibroblasts response to transforming growth factor (TGF)-ß1 and its potential mechanisms. METHOD: Cultured renal fibroblasts (NRK-49F) were exposed to apigenin (1, 5, 10 and 20 µM) followed by the stimulation of TGF-ß1 (2 ng/mL) for 24 h. The markers of fibroblast activation were determined. In order to confirm the anti-fibrosis effect of apigenin, the expression of fibrosis-associated genes in renal fibroblasts was assessed. RESULT: As a consequence, apigenin alleviated fibroblast proliferation and fibroblast-myofibroblast differentiation induced by TGF-ß1. Notably, apigenin significantly inhibited the fibrosis-associated genes expression in renal fibroblasts. Moreover, apigenin treatment significantly increased phosphorylation of AMP-activated protein kinase (AMPK). Apigenin treatment also obviously reduced TGF-ß1 induced phosphorylation of ERK1/2 but not Smad2/3, p38 and JNK MAPK in renal fibroblasts. CONCLUSION: In a summary, these results indicate that apigenin inhibits renal fibroblast proliferation, differentiation and function by AMPK activation and reduced of ERK1/2 phosphorylation, suggesting it could be an attractive therapeutic potential for the treatment of renal fibrosis.

6.
Science ; 367(6481): 1014-1017, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32029689

RESUMO

Immunoglobulin M (IgM) plays a pivotal role in both humoral and mucosal immunity. Its assembly and transport depend on the joining chain (J-chain) and the polymeric immunoglobulin receptor (pIgR), but the underlying molecular mechanisms of these processes are unclear. We report a cryo-electron microscopy structure of the Fc region of human IgM in complex with the J-chain and pIgR ectodomain. The IgM-Fc pentamer is formed asymmetrically, resembling a hexagon with a missing triangle. The tailpieces of IgM-Fc pack into an amyloid-like structure to stabilize the pentamer. The J-chain caps the tailpiece assembly and bridges the interaction between IgM-Fc and the polymeric immunoglobulin receptor, which undergoes a large conformational change to engage the IgM-J complex. These results provide a structural basis for the function of IgM.


Assuntos
Imunoglobulina M/química , Imunoglobulina M/imunologia , Receptores de Imunoglobulina Polimérica/química , Microscopia Crioeletrônica , Humanos , Fragmentos Fc das Imunoglobulinas/química , Fragmentos Fc das Imunoglobulinas/imunologia , Cadeias J de Imunoglobulina/química , Cadeias J de Imunoglobulina/imunologia , Conformação Proteica , Multimerização Proteica
7.
Adv Mater ; 32(14): e1908040, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32080924

RESUMO

Ferroelectric field-effect transistors (FeFETs) are one of the most interesting ferroelectric devices; however, they, usually suffer from low interface quality. The recently discovered 2D layered ferroelectric materials, combining with the advantages of van der Waals heterostructures (vdWHs), may be promising to fabricate high-quality FeFETs with atomically thin thickness. Here, dual-gated 2D ferroelectric vdWHs are constructed using MoS2 , hexagonal boron nitride (h-BN), and CuInP2 S6 (CIPS), which act as a high-performance nonvolatile memory and programmable rectifier. It is first noted that the insertion of h-BN and dual-gated coupling device configuration can significantly stabilize and effectively polarize ferroelectric CIPS. Through this design, the device shows a record-high performance with a large memory window, large on/off ratio (107 ), ultralow programming state current (10-13 A), and long-time endurance (104 s) as nonvolatile memory. As for programmable rectifier, a wide range of gate-tunable rectification behavior is observed. Moreover, the device exhibits a large rectification ratio (3 × 105 ) with stable retention under the programming state. This demonstrates the promising potential of ferroelectric vdWHs for new multifunctional ferroelectric devices.

8.
Food Chem ; 313: 126163, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31945702

RESUMO

The copigmentation effects of polyphenol with different structures vary greatly. Therefore, the aim of this study is to investigate possible interactions in red wine model solutions between oenin and three phenolic compounds: danshensu, caffeic acid and rosmarinic acid. Our results show that the copigmentation of rosmarinic acid is the strongest among the compounds tested. The colourimetric parameters indicate that colour intensity becomes enhanced with increasing concentration of these copigments, leading to darker and more vivid bluish colours. Thermodynamic and quantum chemical investigations are performed to interpret the absorption properties in the visible range. Fluorescence spectroscopy confirms the interaction between caffeic acid and oenin, while FTIR spectroscopic results further suggest a role for hydrogen bonds in the overall process. To our knowledge, this is the first experimentally corroborated direct evidence of hydrogen bonds in copigmentation.


Assuntos
Ácidos Cafeicos/química , Cinamatos/química , Depsídeos/química , Lactatos/química , Vinho , Cor , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Vinho/análise
9.
Adv Mater ; 32(7): e1906874, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31867809

RESUMO

Van der Waals (vdW) heterostructures exhibit excellent optoelectronic properties and novel functionalities. However, their applicability is impeded due to the common issue of the tunneling barrier, which arises from the vdW gap; this significantly increases the injection resistance of the photoexcited carriers. Herein, a generic strategy is demonstrated to eliminate the vdW gap in a broad class of heterostructures. It is observed that the vdW gap in the interface is bridged via strong orbital hybridization between the interface dangling bonds of nonlayered chalcogenide semiconductors and the artificially induced vacancies of transition metal chalcogenides (TMDCs). The photoresponse times of bridged PbS/ReS2 , PbS/MoSe2 , and PbS/MoS2 are ≈30, 51, and 43 µs, respectively. The photon-triggered on/off ratio of the bridged PbS/MoS2 , ZnSe/MoS2 , and ZnTe/MoS2 heterostructures exceed 106 , 105 , and 105 , respectively. These are several orders of magnitude higher than common vdW heterostructures. The findings obtained in this study present a versatile strategy for overcoming the performance limitations of vdW heterostructures.

10.
Nat Plants ; 5(10): 1087-1097, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31595062

RESUMO

Two large protein-cofactor complexes, photosystem I and photosystem II, are the central components of photosynthesis in the thylakoid membranes. Here, we report the 2.37-Å structure of a tetrameric photosystem I complex from a heterocyst-forming cyanobacterium Anabaena sp. PCC 7120. Four photosystem I monomers, organized in a dimer of dimer, form two distinct interfaces that are largely mediated by specifically orientated polar lipids, such as sulfoquinovosyl diacylglycerol. The structure depicts a more closely connected network of chlorophylls across monomer interfaces than those seen in trimeric PSI from thermophilic cyanobacteria, possibly allowing a more efficient energy transfer between monomers. Our physiological data also revealed a functional link of photosystem I oligomerization to cyclic electron flow and thylakoid membrane organization.

11.
Nanoscale ; 11(43): 20497-20506, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31657429

RESUMO

Two-dimensional layered materials have been considered as promising candidates for resistive random access memory, one of the most promising next-generation nonvolatile memories. However, due to the types of defects, most of the devices still suffer from poor environmental stability, defects inducing complexity, and uncontrollability. Here, we fabricate memory cells based on synthesized high-quality two-dimensional layered transition-metal oxide (α-MoO3) nanosheets which can be thinned to 8.68 nm (∼6 layers) and find a unipolar nonvolatile resistive switching behavior. Driven by the migration of intrinsic oxygen vacancies, the devices show a large memory window (∼105), good memory voltage stability, long-term endurance (for durations of over 3 days and 50 manual DC switching cycles) and multi-bit memory states. Furthermore, we find the devices with an excellent temperature tolerance of lower SET/RESET voltages and a larger memory window (>104 at 380 K) at higher temperatures, suggesting their potential in practical applications. Finally, all 2D memory devices are demonstrated using graphene/α-MoO3/graphene heterostructures.

12.
Ecotoxicology ; 28(8): 1003-1008, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31471821

RESUMO

Anaerobic ammonium-oxidizing (anammox) bacteria can play an important role in nitrogen elimination in the environment. However, the effect of heavy metals on anammox bacteria in aquatic ecosystem remains largely unknown. The present study investigated the variability of anammox bacterial community in a freshwater reservoir after a severe heavy metal spill. The richness (Chao1 richness estimator = 2-18), diversity (Shannon index = 0.26-2.04) and community structure of anammox bacteria changed considerably with sampling date, while anammox bacterial abundance (from 1.38 × 105 to 3.09 × 105 anammox bacterial 16S rRNA gene copies per gram dry sediment) was less responsive to metal spill. Anammox bacterial communities were mainly composed of Brocadia- and Anammoxoglobus-like bacteria as well as novel phylotype, however, there relative abundance varied among sampling dates. This work could add the knowledge of the response of anammox bacteria to heavy metal contamination.


Assuntos
Compostos de Amônio/efeitos adversos , Bactérias Anaeróbias/efeitos dos fármacos , Sedimentos Geológicos/química , Metais Pesados/efeitos adversos , Poluentes Químicos da Água/efeitos adversos , Bactérias Anaeróbias/fisiologia , Biodiversidade , Sedimentos Geológicos/microbiologia , Oxirredução , RNA Bacteriano/análise , RNA Ribossômico 16S/análise
13.
Cancer Res ; 79(20): 5159-5166, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31481498

RESUMO

Tumor cells proliferate rapidly and thus are frequently subjected to replication stress and the risk of incomplete duplication of the genome. Fragile sites are replicated late, making them more vulnerable to damage when DNA replication fails to complete. Therefore, genomic alterations at fragile sites are commonly observed in tumors. FRA16D is one of the most common fragile sites in lung cancer, however, the nature of the tumor suppressor genes affected by FRA16D alterations has been controversial. Here, we show that the ATMIN gene, which encodes a cofactor required for activation of ATM kinase by replication stress, is located close to FRA16D and is commonly lost in lung adenocarcinoma. Low ATMIN expression was frequently observed in human lung adenocarcinoma tumors and was associated with reduced patient survival, suggesting that ATMIN functions as a tumor suppressor in lung adenocarcinoma. Heterozygous Atmin deletion significantly increased tumor cell proliferation, tumor burden, and tumor grade in the LSL-KRasG12D; Trp53 F/F (KP) mouse model of lung adenocarcinoma, identifying ATMIN as a haploinsufficient tumor suppressor. ATMIN-deficient KP lung tumor cells showed increased survival in response to replication stress and consequently accumulated DNA damage. Thus, our data identify ATMIN as a key gene affected by genomic deletions at FRA16D in lung adenocarcinoma. SIGNIFICANCE: These findings identify ATMIN as a tumor suppressor in LUAD; fragility at chr16q23 correlates with loss of ATMIN in human LUAD and deletion of Atmin increases tumor burden in a LUAD mouse model.

14.
Cancer Res ; 79(19): 4994-5007, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31391185

RESUMO

Human astrocytomas and oligodendrogliomas are defined by mutations of the metabolic enzymes isocitrate dehydrogenase (IDH) 1 or 2, resulting in the production of the abnormal metabolite D-2 hydroxyglutarate. Here, we studied the effect of mutant IDH on cell proliferation and apoptosis in a glioma mouse model. Tumors were generated by inactivating Pten and p53 in forebrain progenitors and compared with tumors additionally expressing the Idh1 R132H mutation. Idh-mutant cells proliferated less in vitro and mice with Idh-mutant tumors survived significantly longer compared with Idh-wildtype mice. Comparison of miRNA and RNA expression profiles of Idh-wildtype and Idh-mutant cells and tumors revealed miR-183 was significantly upregulated in IDH-mutant cells. Idh-mutant cells were more sensitive to endoplasmic reticulum (ER) stress, resulting in increased apoptosis and thus reduced cell proliferation and survival. This was mediated by the interaction of miR-183 with the 5' untranslated region of semaphorin 3E, downregulating its function as an apoptosis suppressor. In conclusion, we show that mutant Idh1 delays tumorigenesis and sensitizes tumor cells to ER stress and apoptosis. This may open opportunities for drug treatments targeting the miR-183-semaphorin axis. SIGNIFICANCE: The pathologic metabolite 2-hydroxyglutarate, generated by IDH-mutant astrocytomas, sensitizes tumor cells to ER stress and delays tumorigenesis. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/79/19/4994/F1.large.jpg.

15.
ACS Nano ; 13(11): 12662-12670, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31424906

RESUMO

α-MnS, as a nonlayered p-type material with a wide band gap of 2.7 eV, has been expected to supplement the scarcity of two-dimensional (2D) p-type semiconductors, which are desperately required for constructing atomically thin p-n junctions. However, the preparation and property investigation of 2D α-MnS has scarcely been reported so far. Herein, we report the controlled synthesis of ultrathin large-scale α-MnS single crystals down to 4.78 nm via a facile chemical vapor deposition (CVD) method. Importantly, top-gating field-effect transistors based on the as-synthesized α-MnS nanosheets show p-type transport behavior with an ultrahigh on/off ratio exceeding 106, surpassing most reported p-type 2D materials. Meanwhile, α-MnS phototransistors exhibit an ultrahigh detectivity of 3.2 × 1014 Jones, as well as an excellent photoresponsivity of 139 A/W and a fast response time of 12 ms. Besides, outstanding environmental stability and admirable flexibility have also been demonstrated in the as-synthesized α-MnS nanosheets. We believe that this work broadens the scope of the CVD synthesis strategy for various p-type 2D materials and demonstrates their significant application potentials in electronics and optoelectronics.

16.
Nature ; 573(7775): 546-552, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31461748

RESUMO

The αß T cell receptor (TCR), in association with the CD3γε-CD3δε-CD3ζζ signalling hexamer, is the primary determinant of T cell development and activation, and of immune responses to foreign antigens. The mechanism of assembly of the TCR-CD3 complex remains unknown. Here we report a cryo-electron microscopy structure of human TCRαß in complex with the CD3 hexamer at 3.7 Å resolution. The structure contains the complete extracellular domains and all the transmembrane helices of TCR-CD3. The octameric TCR-CD3 complex is assembled with 1:1:1:1 stoichiometry of TCRαß:CD3γε:CD3δε:CD3ζζ. Assembly of the extracellular domains of TCR-CD3 is mediated by the constant domains and connecting peptides of TCRαß that pack against CD3γε-CD3δε, forming a trimer-like structure proximal to the plasma membrane. The transmembrane segment of the CD3 complex adopts a barrel-like structure formed by interaction of the two transmembrane helices of CD3ζζ with those of CD3γε and CD3δε. Insertion of the transmembrane helices of TCRαß into the barrel-like structure via both hydrophobic and ionic interactions results in transmembrane assembly of the TCR-CD3 complex. Together, our data reveal the structural basis for TCR-CD3 complex assembly, providing clues to TCR triggering and a foundation for rational design of immunotherapies that target the complex.

17.
Biomed Pharmacother ; 118: 109230, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31351434

RESUMO

Pulmonary fibrosis is a chronic and progressive interstitial lung disease of known and unknown etiology. Over the past decades, macrophages have been recognized to play a significant role in IPF pathogenesis. According to their anatomical loci, macrophages can be divided to alveolar macrophages (AMs) subtypes and interstitial macrophages subtypes (IMs) with different responsibility in the damage defense response. Depending on diverse chemokines and cytokines in local microenvironments, macrophages can be induced and polarized to either classically activated (M1) or alternatively activated (M2) phenotypes in different stages of immunity. Therefore, we hypothesize that there is a "phagocytosis-secretion-immunization" network regulation of pulmonary macrophages related to a number of chemokines and cytokines. In this paper, we summarize and discuss the role of chemokines and cytokines involved in the "phagocytosis-secretion-immunization" network regulation mechanism of pulmonary macrophages, pointing toward novel therapeutic approaches based on the network target regulation in the field. Therapeutic strategies focused on modifying the chemokines, cytokines and the network are promising for the pharmacotherapy of IPF. Some Traditional Chinese medicines may have more superiorities in delaying the progression of pulmonary fibrosis for their multi-target activities of this network regulation.


Assuntos
Imunização , Macrófagos Alveolares/patologia , Fagocitose , Fibrose Pulmonar/imunologia , Fibrose Pulmonar/terapia , Citocinas/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos
18.
J Plant Physiol ; 239: 38-51, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31181407

RESUMO

Reaumuria trigyna (Reaumuria Linn genus, family Tamaricaceae), an endangered dicotyledonous shrub with the features of a recretohalophyte, is endemic to the Eastern Alxa-Western Ordos area of China. Based on R. trigyna transcriptome data and expression pattern analysis of RtWRKYs, RtWRKY23, a Group II WRKY transcription factor, was isolated from R. trigyna cDNA. RtWRKY23 was mainly expressed in the stem and was induced by salt, drought, cold, ultraviolet radiation, and ABA treatments, but suppressed by heat treatment. Overexpression of RtWRKY23 in Arabidopsis increased chlorophyll content, root length, and fresh weight of the transgenic lines under salt stress. Real-time quantitative PCR (qPCR) analysis and yeast one-hybrid analysis demonstrated that RtWRKY23 protein directly or indirectly modulated the expression levels of downstream genes, including stress-related genes AtPOD, AtPOD22, AtPOD23, AtP5CS1, AtP5CS2, and AtPRODH2, and reproductive development-related genes AtMAF5, AtHAT1, and AtANT. RtWRKY23 transgenic Arabidopsis had higher proline content, peroxidase activity, and superoxide anion clearance rate, and lower H2O2 and malondialdehyde content than WT plants under salt stress conditions. Moreover, RtWRKY23 transgenic Arabidopsis exhibited later flowering and shorter pods, but little change in seed yield, compared with WT plants under salt stress. Our study demonstrated that RtWRKY23 not only enhanced salt stress tolerance through maintaining the ROS and osmotic balances in plants, but also participated in the regulation of flowering under salt stress.


Assuntos
Flores/crescimento & desenvolvimento , Proteínas de Plantas/genética , Tolerância ao Sal/genética , Tamaricaceae/fisiologia , Fatores de Transcrição/genética , Sequência de Aminoácidos , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência , Tamaricaceae/genética , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
19.
Adv Sci (Weinh) ; 6(11): 1801841, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31179206

RESUMO

Barriers that charge carriers experience while injecting into channels play a crucial role on determining the device properties of van der Waals semiconductors (vdWS). Among various strategies to control these barriers, inserting a graphene layer underneath bulk metal may be a promising choice, which is still lacking experimental verification. Here, it is demonstrated that graphene/metal hybrid structures can form quasi-van der Waals contacts (q-vdWC) to ambipolar vdWS, combining the advantages of individual metal and graphene contacts together. A new analysis model is adopted to define the barriers and to extract the barrier heights in ambipolar vdWS. The devices with q-vdWC show significantly reduced Schottky barrier heights and thermionic field emission activation energies, ability of screening the influence from substrate, and Fermi level unpinning effect. Furthermore, phototransistors with these special contacts exhibit enhanced performances. The proposed graphene/metal q-vdWC may be an effective strategy to approach the Schottky-Mott limit for vdWS.

20.
Front Aging Neurosci ; 11: 67, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30971912

RESUMO

A functional brain network, termed the parietal memory network (PMN), has been shown to reflect the familiarity of stimuli in both memory encoding and retrieval. The function of this network has been separated from the commonly investigated default mode network (DMN) in both resting-state fMRI and task-activations. This study examined the deficit of the PMN in Alzheimer's disease (AD) patients using resting-state fMRI and independent component analysis (ICA) and investigated its diagnostic value in identifying AD patients. The DMN was also examined as a reference network. In addition, the robustness of the findings was examined using different types of analysis methods and parameters. Our results showed that the integrity as an intrinsic connectivity network for the PMN was significantly decreased in AD and this feature showed at least equivalent predictive ability to that for the DMN. These findings were robust to varied methods and parameters. Our findings suggest that the intrinsic connectivity of the PMN is disrupted in AD and further call for considering the PMN and the DMN separately in clinical neuroimaging studies.

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