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1.
Nature ; 600(7889): 439-443, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34912084

RESUMO

Fractional Chern insulators (FCIs) are lattice analogues of fractional quantum Hall states that may provide a new avenue towards manipulating non-Abelian excitations. Early theoretical studies1-7 have predicted their existence in systems with flat Chern bands and highlighted the critical role of a particular quantum geometry. However, FCI states have been observed only in Bernal-stacked bilayer graphene (BLG) aligned with hexagonal boron nitride (hBN)8, in which a very large magnetic field is responsible for the existence of the Chern bands, precluding the realization of FCIs at zero field. By contrast, magic-angle twisted BLG9-12 supports flat Chern bands at zero magnetic field13-17, and therefore offers a promising route towards stabilizing zero-field FCIs. Here we report the observation of eight FCI states at low magnetic field in magic-angle twisted BLG enabled by high-resolution local compressibility measurements. The first of these states emerge at 5 T, and their appearance is accompanied by the simultaneous disappearance of nearby topologically trivial charge density wave states. We demonstrate that, unlike the case of the BLG/hBN platform, the principal role of the weak magnetic field is merely to redistribute the Berry curvature of the native Chern bands and thereby realize a quantum geometry favourable for the emergence of FCIs. Our findings strongly suggest that FCIs may be realized at zero magnetic field and pave the way for the exploration and manipulation of anyonic excitations in flat moiré Chern bands.

2.
Nature ; 572(7767): 95-100, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31367030

RESUMO

The electronic properties of heterostructures of atomically thin van der Waals crystals can be modified substantially by moiré superlattice potentials from an interlayer twist between crystals1,2. Moiré tuning of the band structure has led to the recent discovery of superconductivity3,4 and correlated insulating phases5 in twisted bilayer graphene (TBG) near the 'magic angle' of twist of about 1.1 degrees, with a phase diagram reminiscent of high-transition-temperature superconductors. Here we directly map the atomic-scale structural and electronic properties of TBG near the magic angle using scanning tunnelling microscopy and spectroscopy. We observe two distinct van Hove singularities (VHSs) in the local density of states around the magic angle, with an energy separation of 57 millielectronvolts that drops to 40 millielectronvolts with high electron/hole doping. Unexpectedly, the VHS energy separation continues to decrease with decreasing twist angle, with a lowest value of 7 to 13 millielectronvolts at a magic angle of 0.79 degrees. More crucial to the correlated behaviour of this material, we find that at the magic angle, the ratio of the Coulomb interaction to the bandwidth of each individual VHS (U/t) is maximized, which is optimal for electronic Cooper pairing mechanisms. When doped near the half-moiré-band filling, a correlation-induced gap splits the conduction VHS with a maximum size of 6.5 millielectronvolts at 1.15 degrees, dropping to 4 millielectronvolts at 0.79 degrees. We capture the doping-dependent and angle-dependent spectroscopy results using a Hartree-Fock model, which allows us to extract the on-site and nearest-neighbour Coulomb interactions. This analysis yields a U/t of order unity indicating that magic-angle TBG is moderately correlated. In addition, scanning tunnelling spectroscopy maps reveal an energy- and doping-dependent three-fold rotational-symmetry breaking of the local density of states in TBG, with the strongest symmetry breaking near the Fermi level and further enhanced when doped to the correlated gap regime. This indicates the presence of a strong electronic nematic susceptibility or even nematic order in TBG in regions of the phase diagram where superconductivity is observed.

3.
Proc Natl Acad Sci U S A ; 119(16): e2118482119, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35412918

RESUMO

SignificanceWhen two sheets of graphene are twisted to the magic angle of 1.1∘, the resulting flat moiré bands can host exotic correlated electronic states such as superconductivity and ferromagnetism. Here, we show transport properties of a twisted bilayer graphene device at 1.38∘, far enough above the magic angle that we do not expect exotic correlated states. Instead, we see several unusual behaviors in the device's resistivity upon tuning both charge carrier density and perpendicular magnetic field. We can reproduce these behaviors with a surprisingly simple model based on Hofstadter's butterfly. These results shed light on the underlying properties of twisted bilayer graphene.

4.
J Microsc ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819026

RESUMO

High-resolution transmission electron microscopy (HRTEM) images can capture the atomic-resolution details of the dynamically changing structure of nanomaterials. Here, we propose a new scheme and an improved reconstruction algorithm to reconstruct the exit wave function for each image in a focal series of HRTEM images to reveal structural changes. In this scheme, the wave reconstructed from the focal series of images is treated as the initial wave in the reconstruction process for each HRTEM image. Additionally, to suppress noise at the frequencies where the signal is weak due to the modulation of the lens transfer function, a weight factor is introduced in the improved reconstruction algorithm. The advantages of the new scheme and algorithms are validated by using the HRTEM images of a natural specimen and a single-layer molybdenum disulphide. This algorithm enables image resolution enhancement and lens aberration removal, while potentially allowing the visualisation of the structural evolution of nanostructures.

5.
Phys Chem Chem Phys ; 26(22): 16253-16260, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38804578

RESUMO

Dynamic infrared radiation regulation has been widely explored for smart windows because of its vital importance for comfortable and energy-efficient buildings. However, it remains a great challenge to synchronously achieve high visible transmittance and pronounced infrared tunability. Here, we propose a dynamic infrared tunable metamaterial composed of indium tin oxide (ITO) gratings, an air insulator, and an ITO reflector. The ITO grating-based infrared radiation regulator exhibits a high emissivity tunability of 0.73 at 8-13 µm while maintaining a high visible transmittance of 0.65 and 0.72 before and after actuation, respectively. By adjusting the geometric parameters, the tunable bandwidth can be further extended to 3-30 µm and the ultra-broadband tunability reaches 0.62. The excellent infrared tunable performance arises from the insulator thickness-dependent effect of Fabry-Pérot and propagating surface plasmon resonance coupling and decoupling, which lead to perfect and low absorption, respectively. This work provides potential for the advancement of smart window technology and makes a significant contribution to sustainable buildings.

6.
Nanotechnology ; 35(5)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37883949

RESUMO

Selective mid-infrared (MIR) radiation is highly desirable in many applications. However, there are still great challenges to simultaneously achieve MIR camouflage and radiative cooling utilizing simple structure. This work theoretically and experimentally proposes a bi-layer metamaterial composed of aluminum doped zinc oxide (AZO) nanoparticles embedded in Al2O3matrix on the aluminum film. The bi-layer metamaterial exhibits high performance in MIR camouflage with radiative cooling, a low emissivity (ε3-5µm= 0.11,ε8-14µm= 0.20) in atmospheric windows and a high emissivity (ε5-8µm= 0.81) in non-atmospheric windows. The interaction of the epsilon-near-zero (ENZ) mode and localized surface plasmon resonance (LSPR) mode is responsible for the perfect emission over the wavelength range of 5-8µm. Additionally, the proposed selective MIR emitter supports large-angle incidence and has great polarization insensitivity. This demonstrates that epsilon-near-zero material-based bi-layer metamaterial is highly promising for the development of selective mid-infrared radiation.

7.
J Cell Biochem ; 121(2): 1504-1513, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31498486

RESUMO

MicroRNA-96 (miR-96) is a vertebrate conserved microRNA which plays important roles in various cancers including renal cell carcinoma (RCC). However, its function and mechanism in RCC are still unclear. In this study, miR-96 was found to be downregulated in RCC based on The Cancer Genome Atlas datasets analyses, and its target genes, which predicted by TargetScan, were investigated. Among these target genes, neuronal pentraxin 2 (NPTX2) was upregulated more than 15-fold in RCC, and moreover, closely related to patient survival. To validate its targeting of NPTX2 experimentally, reverse transcription polymerase chain reaction, Western blot analysis, and dual-luciferase assays were performed, and results of these assays demonstrated that miR-96 inhibited expression of NPTX2 through a single 3'-untranslated region targeting site. Furthermore, transfection assays in RenCa and 786-O cells showed miR-96 and small interfering RNA of NPTX2 inhibited cell proliferation, migration, and invasion and overexpression of NPTX2 recovered the inhibition of miR-96. In conclusion, the present study reveals a novel regulatory mechanism of miR-96 on NPTX2 expression in RCC, and the potential of miR-96 as a RCC tumor repressor deserves further investigation.


Assuntos
Proteína C-Reativa/biossíntese , Carcinoma de Células Renais/metabolismo , Genes Supressores de Tumor , Neoplasias Renais/metabolismo , MicroRNAs/metabolismo , Proteínas de Neoplasias/biossíntese , Proteínas do Tecido Nervoso/biossíntese , RNA Neoplásico/metabolismo , Proteína C-Reativa/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias Renais/genética , Neoplasias Renais/patologia , MicroRNAs/genética , Proteínas de Neoplasias/genética , Proteínas do Tecido Nervoso/genética , RNA Neoplásico/genética
8.
Nano Lett ; 19(4): 2583-2587, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30839210

RESUMO

Realizing graphene's promise as an atomically thin and tunable platform for fundamental studies and future applications in quantum transport requires the ability to electrostatically define the geometry of the structure and control the carrier concentration, without compromising the quality of the system. Here, we demonstrate the working principle of a new generation of high-quality gate-defined graphene samples, where the challenge of doing so in a gapless semiconductor is overcome by using the ν = 0 insulating state, which emerges at modest applied magnetic fields. In order to verify that the quality of our devices is not compromised, we compare the electronic transport response of different sample geometries, paying close attention to fragile quantum states, such as the fractional quantum Hall states that are highly susceptible to disorder. The ability to define local depletion regions without compromising device quality establishes a new approach toward structuring graphene-based quantum transport devices.

9.
Phys Rev Lett ; 122(2): 026802, 2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30720304

RESUMO

We report experimental observation of the reentrant integer quantum Hall effect in graphene, appearing in the N=2 Landau level. Similar to high-mobility GaAs/AlGaAs heterostructures, the effect is due to a competition between incompressible fractional quantum Hall states, and electron solid phases. The tunability of graphene allows us to measure the B-T phase diagram of the electron solid phase. The hierarchy of reentrant states suggests spin and valley degrees of freedom play a role in determining the ground state energy. We find that the melting temperature scales with magnetic field, and construct a phase diagram of the electron liquid-solid transition.

10.
Curr Microbiol ; 76(7): 872-878, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31079192

RESUMO

A rod-shaped, Gram-negative and aerobic bacterium, strain XWS2, was isolated from rhizosphere soil of a camphor tree in Hubei University of Chinese Medicine Huangjiahu Campus, Wuhan, China. Cells grew at 4-37 °C (optimum 28 °C), pH 5.0-9.0 (optimum 7.0) and with 0-5% NaCl (optimum 1%). Colonies growing on tryptone soybean agar are round, beige in color and approximately 2 mm in diameter after 24 h incubation at 28 °C. Pellicle formation during liquid culture and strong fluorescent pigment production on King's B medium are typical features of strain XWS2. The genome of XWS2 is 6,170,117 bp, containing 5682 predicted genes and 4770 genes are functionally annotated. Phylogenetic analysis based on 16S rRNA sequence showed that strain XWS2 formed an independent branch within the Pseudomonas putida group, with P. putida NBRC 14164T (99.86% similarity) and P. alkylphenolica KL28T (99.36% similarity) as the most closely related type strains. Genome sequence analysis based on average nucleotide identity and digital DNA-DNA hybridization are below the threshold values for species delineation. Phenotypic characteristics, physiological and biochemical tests also supported the strain represents a separate novel species within the Pseudomonas genus. The name Pseudomonas hutmensis sp. nov. is proposed, with type strain XWS2T (= CCTCC AB 2018189 T = KACC 19898T).


Assuntos
Pigmentos Biológicos/metabolismo , Pseudomonas putida/classificação , Pseudomonas putida/fisiologia , Microbiologia do Solo , Composição de Bases , China , Cinnamomum camphora/microbiologia , DNA Bacteriano/genética , Fluorescência , Genoma Bacteriano/genética , Hibridização de Ácido Nucleico , Filogenia , Pseudomonas putida/genética , RNA Ribossômico 16S/genética , Rizosfera , Análise de Sequência de DNA , Especificidade da Espécie
11.
Nanotechnology ; 25(50): 505201, 2014 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-25427134

RESUMO

As one of the most promising candidates for future nanoelectronic devices, tunnel field-effect transistors (TFET) can overcome the subthreshold slope (SS) limitation of MOSFET, whereas high ON-current, low OFF-current and steep switching can hardly be obtained at the same time for experimental TFETs. In this paper, we developed a new nanodevice technology based on TFET concepts. By designing the gate configuration and introducing the optimized Schottky junction, a multi-finger-gate TFET with a dopant-segregated Schottky source (mFSB-TFET) is proposed and experimentally demonstrated. A steeper SS can be achieved in the fabricated mFSB-TFET on the bulk Si substrate benefiting from the coupled quantum band-to-band tunneling (BTBT) mechanism, as well as a high I(ON)/I(OFF) ratio (∼ 10(7)) at V(DS) = 0.2 V without an area penalty. By compatible SOI CMOS technology, the fabricated Si mFSB-TFET device was further optimized with a high ION/IOFF ratio of ∼ 10(8) and a steeper SS of over 5.5 decades of current. A minimum SS of below 60 mV dec(-1) was experimentally obtained, indicating its dominant quantum BTBT mechanism for switching.

12.
Environ Pollut ; 354: 124183, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38772513

RESUMO

Soil organic matter (SOM) significantly impacts the detection accuracy of Cd2+ and Pb2+ using square wave anodic stripping voltammetry (SWASV) due to the complexation of SOM to heavy metal ions (HMIs), thereby attenuating SWASV signals. This study explored an effective pretreatment method that combined low-pressure ultraviolet (LPUV) photolysis with the ZnO/g-C3N4 photocatalyst, activating the photocatalyst to generate highly oxidative •OH radicals and O2•- radicals, which effectively disrupted this complexation, consequently restoring the electroactivity of HMIs and achieving high-fidelity SWASV signals. The parameters of the LPUV-ZnO/g-C3N4 photocatalytic system were meticulously optimized, including the pH of photolysis, duration of photolysis, g-C3N4 mass fraction, and concentration of the photocatalyst. Furthermore, the ZnO/g-C3N4 photocatalyst was thoroughly characterized, with an in-depth investigation on the synergistic interaction between ZnO and g-C3N4 and the mechanisms contributing to the restoration of SWASV signals. This synergistic interaction effectively separated charge carriers and reduced charge transfer resistance, enabling photogenerated electrons (e-) from the conduction band of g-C3N4 to be quickly transferred to the conduction band of ZnO, preventing the recombination of e- and hole (h+) and generating more radicals to disrupt complexation and restore the SWASV signals. Finally, the analysis of HMIs in real soil extracts using the proposed pretreatment method demonstrated high detection accuracy of 94.9% for Cd2+ and 99.8% for Pb2+, which validated the feasibility and effectiveness of the proposed method in environmental applications.


Assuntos
Cádmio , Chumbo , Poluentes do Solo , Solo , Raios Ultravioleta , Óxido de Zinco , Óxido de Zinco/química , Poluentes do Solo/análise , Solo/química , Catálise , Técnicas Eletroquímicas/métodos , Fotólise , Nitrilas/química , Grafite/química , Compostos de Nitrogênio
13.
Infect Drug Resist ; 16: 463-476, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36721630

RESUMO

Background: China has seen a drastic increase in the incidence of non-tuberculous mycobacteria (NTM) infection, which is a notable public health issue. Due to a lack of reliable epidemiological surveillance information, there is a need to gather accurate epidemiological and surveillance data, which can help clinicians effectively treat NTM patients. Moreover, drug susceptibility testing for NTM is not frequently performed in China. This retrospective study, therefore, determined the prevalence and resistance characteristics of NTM to provide a reference to control the NTM epidemic. Methods: Sputum, alveolar lavage fluid, and other respiratory specimens were collected from 3025 patients with suspected pulmonary tuberculosis attending The Second Affiliated Hospital of Hainan Medical University from January 2014 to December 2021. Strain identification and species distribution of NTM were performed by DNA chip technology and gene sequencing, and the drug resistance of NTM isolates was evaluated by calculating the minimum inhibitory concentration through antimicrobial susceptibility testing for NTM. Results: From 2014 to 2021, 373 strains of NTM were isolated and identified from respiratory specimens of 3025 suspected tuberculosis patients. Except in 2014, NTM-infected patients accounted for more than 10% of suspected tuberculosis patients in other years. The median age of patients with NTM infection was 62.0 years (53.0, 71.0), and the male-to-female ratio among these patients was 0.79:1. Among culture-positive strains, 12.3% (373/3040; 95% CI 11.1-13.4%) were identified as NTM comprising forty species of NTM. The forty species of NTM included 23 slow-growing mycobacteria (SGM) and 17 rapidly-growing mycobacteria (RGM). Among the NTM isolates, 58.7% (219/373; 95% CI 53.7-63.7%) were SGM and 41.3% (154/373; 95% CI 36.3-46.3%) were RGM. M.avium complex(MAC)(41.3%; 95% CI 36.3-46.3%) and M.abscessus complex (MABC)(33.2%; 95% CI 28.4-38.0%) were the most frequently detected species, followed by M.simiae Complex (11.8%; 95% CI 8.5-15.1%), M.fortuitum group (5.1%; 95% CI 2.9-7.3%), and others. Drug sensitivity test results showed that most of the NTM isolates were susceptible to amikacin and clarithromycin with a drug resistance rate of less than 10%. However, clarithromycin could induce drug resistance, followed by linezolid and moxifloxacin, and their drug resistance rate was less than 50%. Conclusion: During 2014-2021, the number of NTM isolates detected in the respiratory specimens of the study patients in The Second Affiliated Hospital of Hainan Medical University increased year by year. M. intracellulare is the most common pathogenic NTM species, and there is a high incidence of NTM infection on Hainan Island. Our findings might be of great importance for diagnosing and treating this patient population in Hainan.

14.
Front Cell Infect Microbiol ; 13: 1115268, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36816584

RESUMO

We reported a 31-year-old man who received renal transplantation for more than 2 years. He was admitted to our hospital on 9 March 2022 due to intermittent diarrhea accompanied by leukopenia for more than 1 month. The patient successively developed high fever, cough, anemia, weight loss, gastrointestinal bleeding, and liver function impairment. Computed tomography (CT) revealed a slight inflammation in the lower lobes of both lungs, enlargement of the lymph nodes in the retroperitoneal and the root of mesenteric areas, and hepatosplenomegaly. Talaromyces marneffei was detected by metagenomics next-generation sequencing (mNGS) in blood and bronchoalveolar lavage fluid, and the pathogen was subsequently verified by blood culture. After endoscopic hemostatic therapy and antifungal therapy with voriconazole and amphotericin B cholesteryl sulfate complex, the patient was successfully discharged. Oral voriconazole was given regularly after discharge. Diarrhea, fever, enlargement of the lymph nodes, and endoscopic evidence of erosion may indicate intestinal T. marneffei infection. Although the mortality of T. marneffei infection after renal transplantation is very high, timely and effective antifungal therapy with amphotericin B cholesteryl sulfate complex is still expected to improve its prognosis.


Assuntos
Antifúngicos , Transplante de Rim , Masculino , Humanos , Adulto , Antifúngicos/uso terapêutico , Anfotericina B , Voriconazol
15.
Infect Drug Resist ; 16: 5783-5798, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692467

RESUMO

Purpose: Given the high burden of Tuberculosis (TB) in China, the prevalence of multidrug-resistant tuberculosis (MDR-TB) is significant. Whole-genome sequencing (WGS) of Mycobacterium tuberculosis (MTB) enables the identification of lineages, drug-resistant mutations, and transmission patterns, offering valuable insights for TB control, clinical diagnosis, and treatment. Methods: We collected 202 MDR-MTB strains from 3519 suspected pulmonary TB patients treated at The Second Affiliated Hospital of Hainan Medical University between July 2019 and June 2021. Proportional drug-susceptibility testing was performed using 8 common anti-tuberculosis drugs. Subsequently, the genotypic drug resistance and genetic characteristics were analyzed by the WGS. Results: Lineages are identified by TB-profiler revealed 202 MDR-MTB strains, showcasing three predominant lineages, with lineage 2 being the most prevalent. Close genomic relatedness analysis and evidence of MTB transmission led to the formation of 15 clusters comprising 42 isolates, resulting in a clustering rate of 20.8%. Novelty, lineage 2.1 (non-Beijing) accounted for 27.2% of the MDR-MTB strains, which is rare in China and Neighboring countries. Regarding first-line anti-TB drugs, genes associated with rifampicin resistance, primarily the rpoB gene, were detected in 200 strains (99.0%). Genes conferring resistance to isoniazid, ethambutol, and streptomycin were identified in 191 (94.5%), 125 (61.9%), and 100 (49.5%) strains, respectively. Among the second-line drugs, 97 (48.0%) strains exhibited genes encoding resistance to fluoroquinolones. Comparing the results to phenotypic drug susceptibility-based testing, the sensitivity of WGS for detecting resistance to each of the six drugs (rifampicin, isoniazid, ethambutol, ofloxacin, kanamycin, capreomycin) was 90% or higher. With the exception of ethambutol, the specificity of WGS prediction for the remaining drugs exceeded 88%. Conclusion: Our study provides crucial insights into genetic mutation types, genetic diversity, and transmission of MDR-MTB on Hainan Island, serving as a significant reference for MDR-MTB surveillance and clinical decision-making.

16.
Chemosphere ; 344: 140270, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37775056

RESUMO

Humic acid (HA), the primary composition of natural organic matter (NOM) widely distributed in water and soil, can complex with heavy metal ions (HMIs), i.e., Cd(II) and Pb(II) in this study, which deters the accurate detection of HMIs using square wave anodic stripping voltammetry (SWASV). Hence, in this study, an efficient pretreatment method was proposed to restore the electrochemical signal of Cd(II) and Pb(II) by breaking the complexation based on AgNPs-doped SnO2 photocatalyst combined with LP/UV irradiation. Optimization of the key parameters for electrochemical signal restoration including pH for photolysis, AgNPs doping rate, photocatalyst dosage and photolysis time were performed to further elevating the accuracy in the proposed pretreatment method over 96.9% for Cd(II) and Pb(II) in 15 min. The effect of different HA concentrations on SWASV signal of Cd(II) and Pb(II) was also investigated adopting the optimal parameters. Then, the UV-vis absorption spectra, crystal structure, and the morphology of AgNPs-doped SnO2 photocatalyst were investigated to excavate the reasons behind the most excellent AgNPs doping rate to SnO2 in signal restoration. Moreover, the behavior of HA degradation and transformation under LP/UV irradiation was studied to investigate the mechanism of electrochemical signal restoration. Finally, the feasibility of the proposed method was testified by comparing detection results with ICP-MS results using real water samples extracted from aquaculture water.


Assuntos
Cádmio , Metais Pesados , Chumbo , Metais Pesados/química , Eletrodos , Água/química , Substâncias Húmicas/análise
17.
Int Urol Nephrol ; 55(9): 2285-2293, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36867374

RESUMO

BACKGROUND: The harmful effect of diabetes mellitus (DM) on mortality in patients with heart failure with reduced ejection fraction (HFrEF) remains controversial. Furthermore, it seems that no consistent conclusion on whether chronic kidney disease (CKD) modifies the relationship of DM and poor prognosis in patients with HFrEF. METHODS: We analyzed the individuals with HFrEF from the Cardiorenal ImprovemeNt (CIN) cohort between January 2007 and December 2018. The primary endpoint was all-cause mortality. The patients were divided into four groups (control vs. DM alone vs. CKD alone vs. DM and CKD). Multivariate Cox proportional hazards analysis was conducted to examine the association among DM, CKD and all-cause mortality. RESULTS: There were 3,273 patients included in this study (mean age: 62.7 ± 10.9 years, 20.4% were female). During a median follow-up of 5.0 years (interquartile range: 3.0-7.6 years), 740 (22.6%) patients died. Patients with DM have a higher risk of all-cause mortality (HR [95% confidence interval (CI)]:1.28[1.07-1.53]) than those without DM. In patients with CKD, DM had a 61% (HR [95% CI]:1.61[1.26-2.06]) increased adjusted risk of death relative to non-DM, while in patients with non-CKD, there was no significantly difference in risk of all-cause mortality (HR [95% CI]:1.01[0.77-1.32]) between DM and non-DM (p for interaction = 0.013). CONCLUSIONS: Diabetes is a potent risk factor for mortality in patients with HFrEF. Furthermore, DM had a substantially different effect on all-cause mortality depending on CKD. The association between DM and all-cause mortality was only observed in patients with CKD.


Assuntos
Diabetes Mellitus , Insuficiência Cardíaca , Insuficiência Renal Crônica , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Insuficiência Cardíaca/complicações , Volume Sistólico , Diabetes Mellitus/epidemiologia , Fatores de Risco , Insuficiência Renal Crônica/complicações , Rim/fisiologia
18.
World J Gastroenterol ; 29(22): 3469-3481, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37389235

RESUMO

BACKGROUND: Wild rats have the potential to hold zoonotic infectious agents that can spread to humans and cause disease. AIM: To better understand the composition of gut bacterial communities in rats is essential for preventing and treating such diseases. As a tropical island located in the south of China, Hainan province has abundant rat species. Here, we examined the gut bacterial composition in wild adult rats from Hainan province. METHODS: Fresh fecal samples were collected from 162 wild adult rats, including three species (Rattus norvegicus, Leopoldamys edwardsi, and Rattus losea), from nine regions of Hainan province between 2017-2018. RESULTS: We analyzed the composition of gut microbiota using the 16S rRNA gene amplicon sequencing. We identified 4903 bacterial operational taxonomic units (30 phyla, 175 families, and 498 genera), which vary between samples of different rat species in various habitats at various times of the year. In general, Firmicutes were the most abundant phyla, followed by Bacteroidetes (15.55%), Proteobacteria (6.13%), and Actinobacteria (4.02%). The genus Lactobacillus (20.08%), unidentified_Clostridiales (5.16%), Romboutsia (4.33%), unidentified_Ruminococcaceae (3.83%), Bacteroides (3.66%), Helicobacter (2.40%) and Streptococcus (2.37%) were dominant. CONCLUSION: The composition and abundance of the gut microbial communities varied between rat species and locations. This work provides fundamental information to identify microbial communities useful for disease control in Hainan province.


Assuntos
Microbioma Gastrointestinal , Microbiota , Humanos , Adulto , Ratos , Animais , RNA Ribossômico 16S/genética , China , Bacteroides , Clostridiales
19.
Clin Interv Aging ; 18: 2053-2061, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38088947

RESUMO

Background: The association between uric acid (UA) and contrast-induced acute kidney injury (CI-AKI) following coronary angiography (CAG) has been established. However, whether the association would vary with age remained undetermined. Methods: We performed the retrospective analysis based on the Cardio-renal Improvement II study, (ClinicalTrials.gov NCT05050877), which enrolled consecutive patients undergoing coronary angiography in 5 teaching hospitals in China from 2007 to 2020. The primary outcome was CI-AKI defined as the rise of serum creatinine (SCr) ≥ 0.5 mg/dL or 25% compared with the baseline value within 48 hours following CAG. The effect of age on the association between uric acid and CI-AKI was assessed by the logistic regression model. Results: A total of 36,550 patients (mean age 63.08±5.6-year-old, 41.7% men) were included in the study. After adjusting for the confounders, the risk of CI-AKI between each quartile of uric acid was insignificant in the young group. In patients of the middle group, lower UA was associated with a lower risk of CI-AKI while higher UA was associated with a higher risk (Q1 OR: 0.853, 95% CI: 0.734-0.993; Q4 OR: 1.797, 95% CI: 1.547-2.09). In patients of the elder group, lower and higher UA were both associated with a higher risk of CI-AKI (Q1 OR: 1.247, 95% CI: 1.003-1.553; Q4 OR: 1.688, 95% CI: 1.344-2.124). The restricted cubic spline indicated a non-linear association between UA and CI-AKI in middle and elder age groups but a linear association in the young age group. Conclusion: The association between uric acid and CI-AKI vary in patients of different age. Patients with elder age should maintain a middle level of uric acid while patients with middle age should consider a lower level of uric acid to reduce the risk of CI-AKI. The level of UA was an insignificant risk factor for CI-AKI in young patients.


Assuntos
Injúria Renal Aguda , Intervenção Coronária Percutânea , Masculino , Humanos , Idoso , Feminino , Angiografia Coronária/efeitos adversos , Meios de Contraste/efeitos adversos , Ácido Úrico , Estudos Retrospectivos , Fatores de Risco , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/epidemiologia , Intervenção Coronária Percutânea/efeitos adversos
20.
Science ; 381(6654): 181-186, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37319246

RESUMO

Quantum geometry in condensed-matter physics has two components: the real part quantum metric and the imaginary part Berry curvature. Whereas the effects of Berry curvature have been observed through phenomena such as the quantum Hall effect in two-dimensional electron gases and the anomalous Hall effect (AHE) in ferromagnets, the quantum metric has rarely been explored. Here, we report a nonlinear Hall effect induced by the quantum metric dipole by interfacing even-layered MnBi2Te4 with black phosphorus. The quantum metric nonlinear Hall effect switches direction upon reversing the antiferromagnetic (AFM) spins and exhibits distinct scaling that is independent of the scattering time. Our results open the door to discovering quantum metric responses predicted theoretically and pave the way for applications that bridge nonlinear electronics with AFM spintronics.

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