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1.
Plant Commun ; : 100937, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38693694

RESUMEN

The crosstalk between clathrin-mediated endocytosis (CME) and autophagy pathway has been reported in mammals. However, the interconnection of CME with autophagy has not been established in plants. In this report, we showed that Arabidopsis CLATHRIN LIGHT CHAIN (CLC) subunit 2 and 3 double mutant, clc2-1 clc3-1, phenocopied the Arabidopsis AUTOPHAGY-RELATED GENE (ATG) mutants both in auto-immunity and nutrient sensitivity. Accordingly, the autophagy pathway was significantly compromised in the clc2-1 clc3-1 mutant. Interestingly, we demonstrated with multiple assays that CLC2 directly interacted with ATG8h/ATG8i in a domain-specific manner. As expected, both GFP-ATG8h/GFP-ATG8i and CLC2-GFP were subjected to autophagic degradation and the degradation of GFP-ATG8h was significantly reduced in the clc2-1 clc3-1 mutant. Notably, simultaneously knocking out ATG8h and ATG8i by the CRISPR/CAS9 resulted in an enhanced resistance against Golovinomyces cichoracearum, supporting the functional relevance of the CLC2-ATG8h/8i interactions. In conclusion, our results uncovered a link between the function of CLCs and the autophagy pathway in Arabidopsis.

2.
Int Urol Nephrol ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38632173

RESUMEN

INTRODUCTION: The commonly used clinical indicators are not sensitive and comprehensive enough to evaluate the early staging of chronic kidney disease (CKD). This study aimed to evaluate the differences in arterial spin labeling (ASL) and blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-MRI) parameter values among patients at various stages of chronic kidney disease and healthy individuals. METHODS: Electronic databases PubMed, Web of Science, Cochrane, and Embase were searched from inception to March 29, 2024, to identify relevant studies on ASL and BOLD in CKD. The renal blood flow (RBF) and apparent relaxation rate (R2*) values were obtained from healthy individuals and patients with various stages of CKD. The meta-analysis was conducted using STATA version 12.0. The random-effects model was used to obtain estimates of the effects, and the results were expressed as 95% confidence intervals (CIs) and mean differences (MDs) of continuous variables. RESULTS: A total of 18 published studies were included in this meta-analysis. The cortical RBF and R2* values and medulla RBF values were considerably distinct between patients with various stages of CKD and healthy controls (MD, - 78.162; 95% CI, - 85.103 to - 71.221; MD, 2.440; 95% CI, 1.843 to 3.037; and MD, - 36.787; 95% CI, - 47.107 to - 26.468, respectively). No obvious difference in medulla R2* values was noted between patients with various stages of CKD and healthy controls (MD, - 1.475; 95% CI, - 4.646 to 1.696). CONCLUSION: ASL and BOLD may provide complementary and distinct information regarding renal function and could potentially be used together to gain a more comprehensive understanding of renal physiology.

3.
Nature ; 628(8008): 515-521, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38509374

RESUMEN

The convergence of topology and correlations represents a highly coveted realm in the pursuit of new quantum states of matter1. Introducing electron correlations to a quantum spin Hall (QSH) insulator can lead to the emergence of a fractional topological insulator and other exotic time-reversal-symmetric topological order2-8, not possible in quantum Hall and Chern insulator systems. Here we report a new dual QSH insulator within the intrinsic monolayer crystal of TaIrTe4, arising from the interplay of its single-particle topology and density-tuned electron correlations. At charge neutrality, monolayer TaIrTe4 demonstrates the QSH insulator, manifesting enhanced nonlocal transport and quantized helical edge conductance. After introducing electrons from charge neutrality, TaIrTe4 shows metallic behaviour in only a small range of charge densities but quickly goes into a new insulating state, entirely unexpected on the basis of the single-particle band structure of TaIrTe4. This insulating state could arise from a strong electronic instability near the van Hove singularities, probably leading to a charge density wave (CDW). Remarkably, within this correlated insulating gap, we observe a resurgence of the QSH state. The observation of helical edge conduction in a CDW gap could bridge spin physics and charge orders. The discovery of a dual QSH insulator introduces a new method for creating topological flat minibands through CDW superlattices, which offer a promising platform for exploring time-reversal-symmetric fractional phases and electromagnetism2-4,9,10.

4.
Int Health ; 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38551313

RESUMEN

BACKGROUND: Pre-exposure prophylaxis (PrEP) is effective for human immunodeficiency virus (HIV) prevention in risk groups. We assessed PrEP uptake and 12-month retention among men who have sex with men (MSM) and transgender women (TGW) in Myanmar during the coronavirus disease 2019 pandemic and a political crisis. METHODS: Using prospectively collected data, we assessed the proportion of persons eligible, initiated and retained 12 months on PrEP. We calculated HIV and syphilis incidence among those initiated on PrEP. Predictors of compliance to scheduled visits were assessed with fractional logistic regression. RESULTS: Among 652 persons screened between July and December 2020, 85.3% were eligible and 38.8% initiated PrEP. The daily pill burden was the main reason (86.5%) for refusing PrEP. A history of HIV post-exposure prophylaxis (PEP) and having an HIV-positive partner not on anti-retroviral therapy (ART) was associated with PrEP uptake (p<0.05). The 12-month retention among those initiating PrEP was 43.0%. Age ≥25 y, a history of PEP and having an HIV-positive partner not on ART predicted better compliance with scheduled visits (p<0.05). HIV incidence among PrEP initiators was 3.1 per 100 person-years (95% confidence interval [CI] 1.3 to 7.4) and syphilis incidence was 17.6 per 100 person-years (95% CI 12.3 to 25.1). CONCLUSIONS: A PrEP program for MSM and TGW in Myanmar was implemented successfully under difficult circumstances. Alternative strategies are needed addressing PrEP uptake and retention.

5.
Alcohol ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38387693

RESUMEN

OBJECTIVES: Alcohol consumption is not uncommon among people with HIV (PWH) and may exacerbate HIV-induced intestinal damage, and further lead to dysbiosis and increased intestinal permeability. This study aimed to determine the changes in the faecal microbiota and its association with alcohol consumption in HIV-infected patients. METHODS: A cross-sectional survey was conducted between November 2021 and May 2022, and 93 participants were recruited. To investigate the alterations of alcohol misuse on fecal microbiology in HIV-infected individuals, we performed 16s rDNA gene sequencing on fecal samples from the low to moderate drinking (n=21) and non-drinking (n=72) groups. RESULTS: Comparison between groups using alpha and beta diversity showed that the diversity of stool microbiota in the low to moderate drinkinge group did not differ from that of the non-drinking group (all P>0.05). The Linear discriminant Analysis effect size (LEfSe) algorithm was to determine the bacterial taxa associated with alcohol consumption, and the results showed altered fecal bacterial composition in HIV-infected patients who consumed alcohol, with Coprobacillus, Pseudobutyrivibrio and Peptostreptococcaceae enriched, and Pasteurellaceae and Xanthomonadaceae were depleted. In addition, by using the Kyoto Encyclopedia of Genes and Genomes (KEGG) functional microbiome features were also found to be altered in the low to moderate drinking group, showing a reduction in metabolic pathways (P=0.036) and cardiovascular disease pathway (P=0.006). CONCLUSION: Low to moderate drinking will change the composition, metabolism and cardiovascular disease pathway of the gut microbiota of HIV-infected patients.

6.
Natl Sci Rev ; 11(2): nwad282, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38213523

RESUMEN

The search for magnetic topological materials has been at the forefront of condensed matter research for their potential to host exotic states such as axion insulators, magnetic Weyl semimetals, Chern insulators, etc. To date, the MnBi2nTe3n+1 family is the only group of materials showcasing van der Waals-layered structures, intrinsic magnetism and non-trivial band topology without trivial bands at the Fermi level. The interplay between magnetism and band topology in this family has led to the proposal of various topological phenomena, including the quantum anomalous Hall effect, quantum spin Hall effect and quantum magnetoelectric effect. Among these, the quantum anomalous Hall effect has been experimentally observed at record-high temperatures, highlighting the unprecedented potential of this family of materials in fundamental science and technological innovation. In this paper, we provide a comprehensive review of the research progress in this intrinsic magnetic topological insulator family, with a focus on single-crystal growth, characterization of chemical disorder, manipulation of magnetism through chemical substitution and external pressure, and important questions that remain to be conclusively answered.

7.
J Org Chem ; 89(3): 1633-1647, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38235569

RESUMEN

A metal-free and atom-economic route for the synthesis of naphtho[1,2-b]furan-3-ones has been realized via p-TsOH·H2O-catalyzed intramolecular tandem double cyclization of γ-hydroxy acetylenic ketones with alkynes in formic acid. The benzene-linked furanonyl-ynes are the key intermediates obtained by the scission/recombination of C-O double bonds. Further, the structural modifications of the representative product were implemented by reduction, demethylation, substitution, and [5 + 2]-cycloaddition.

9.
RMD Open ; 9(4)2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-38035758

RESUMEN

OBJECTIVE: To investigate the relationship between metabolomic profiles, genome-wide polygenic risk scores (PRSs) and risk of rheumatoid arthritis (RA). METHODS: 143 nuclear magnetic resonance-based plasma metabolic biomarkers were measured among 93 800 participants in the UK Biobank. The Cox regression model was used to assess the associations between these metabolic biomarkers and RA risk, and genetic correlation and Mendelian randomisation analyses were performed to reveal their causal relationships. Subsequently, a metabolic risk score (MRS) comprised of the weighted sum of 17 clinically validated metabolic markers was constructed. A PRS was derived by assigning weights to genetic variants that exhibited significant associations with RA at a genome-wide level. RESULTS: A total of 620 incident RA cases were recorded during a median follow-up time of 8.2 years. We determined that 30 metabolic biomarkers were potentially associated with RA, while no further significant causal associations were found. Individuals in the top decile of MRS had an increased risk of RA (HR 3.52, 95% CI: 2.80 to 4.43) compared with those below the median of MRS. Further, significant gradient associations between MRS and RA risk were observed across genetic risk strata. Specifically, compared with the low genetic risk and favourable MRS group, the risk of incident RA in the high genetic risk and unfavourable MRS group has almost elevated by fivefold (HR 6.10, 95% CI: 4.06 to 9.14). CONCLUSION: Our findings suggested the metabolic profiles comprising multiple metabolic biomarkers contribute to capturing an elevated risk of RA, and the integration of genome-wide PRSs further improved risk stratification.


Asunto(s)
Artritis Reumatoide , Bancos de Muestras Biológicas , Humanos , Estudios de Cohortes , Factores de Riesgo , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/epidemiología , Artritis Reumatoide/genética , Biomarcadores , Reino Unido/epidemiología
11.
Nat Commun ; 14(1): 5558, 2023 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-37689721

RESUMEN

In multilayered magnetic topological insulator structures, magnetization reversal processes can drive topological phase transitions between quantum anomalous Hall, axion insulator, and normal insulator states. Here we report an examination of the critical behavior of two such transitions: the quantum anomalous Hall to normal insulator (QAH-NI), and quantum anomalous Hall to axion insulator (QAH-AXI) transitions. By introducing a new analysis protocol wherein temperature dependent variations in the magnetic coercivity are accounted for, the critical behavior of the QAH-NI and QAH-AXI transitions are evaluated over a wide range of temperature and magnetic field. Despite the uniqueness of these different transitions, quantized longitudinal resistance and Hall conductance are observed at criticality in both cases. Furthermore, critical exponents were extracted for QAH-AXI transitions occurring at magnetization reversals of two different magnetic layers. The observation of consistent critical exponents and resistances in each case, independent of the magnetic layer details, demonstrates critical behaviors in quantum anomalous Hall transitions to be of electronic rather than magnetic origin. Our finding offers a new avenue for studies of phase transition and criticality in QAH insulators.

12.
Nano Lett ; 23(17): 8099-8105, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37656017

RESUMEN

van der Waals (vdW) magnets, an emerging family of two-dimensional (2D) materials, have received tremendous attention due to their rich fundamental physics and significant potential for cutting-edge technological applications. In contrast to the conventional bulk counterparts, vdW magnets exhibit significant tunability of local material properties, such as stacking engineered interlayer coupling and layer-number dependent magnetic and electronic interactions, which promise to deliver previously unavailable merits to develop multifunctional microelectronic devices. As a further ingredient of this emerging topic, here we report nanoscale quantum sensing and imaging of the atomically thin vdW magnet chromium thiophosphate CrPS4, revealing its characteristic layer-dependent 2D static magnetism and dynamic spin fluctuations. We also show a large tunneling magnetoresistance in CrPS4-based spin filter vdW heterostructures. The excellent material stability and robust strategy against environmental degradation in combination with tailored magnetic properties highlight the potential of CrPS4 in developing state-of-the-art 2D spintronic devices for next-generation information technologies.

13.
Sensors (Basel) ; 23(12)2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37420795

RESUMEN

In this study, we utilized a sapphire substrate with a matrix protrusion structure as a template. We employed a ZnO gel as a precursor and deposited it onto the substrate using the spin coating method. After undergoing six cycles of deposition and baking, a ZnO seed layer with a thickness of 170 nm was formed. Subsequently, we used a hydrothermal method to grow ZnO nanorods (NRs) on the aforementioned ZnO seed layer for different durations. ZnO NRs exhibited a uniform outward growth rate in various directions, resulting in a hexagonal and floral morphology when observed from above. This morphology was particularly evident in ZnO NRs synthesized for 30 and 45 min. Due to the protrusion structure of ZnO seed layer, the resulting ZnO nanorods (NRs) displayed a floral and matrix morphology on the protrusion ZnO seed layer. To further enhance their properties, we utilized Al nanomaterial to decorate the ZnO nanoflower matrix (NFM) using a deposition method. Subsequently, we fabricated devices using both undecorated and Al-decorated ZnO NFMs and deposited an upper electrode using an interdigital mask. We then compared the gas-sensing performance of these two types of sensors towards CO and H2 gases. The research findings indicate that sensors based on Al-decorated ZnO NFM exhibit superior gas-sensing properties compared to undecorated ZnO NFM for both CO and H2 gases. These Al-decorated sensors demonstrate faster response times and higher response rates during the sensing processes.


Asunto(s)
Nanoestructuras , Óxido de Zinc , Óxido de Aluminio , Electrodos , Gases
14.
AIDS Res Ther ; 20(1): 45, 2023 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-37452359

RESUMEN

BACKGROUND: This study conducted a survey of men who have sex with men (MSM) in Maanshan City of Anhui Province to assess the risk behaviors related to human immunodeficiency virus (HIV) infection. METHODS: A cross-sectional survey was conducted from June 2016 to June 2019. The MSM were recruited by a peer-driven sampling method. A face-to-face interview with anonymous questionnaire was used for data collection. The information collected by the survey was summarized and epidemiology described the basic characteristics of MSM, and then the related factors were statistically analyzed. RESULTS: A total of 934 MSM were recruited with a average age was 30.5 (SD = 8.90) years old, including 816 (87.4%) HIV negative participants and 118 (12.6%) HIV positive ones. This study showed that freelancer (OR = 4.02, 95% CI: 1.96-8.23), scope of sexual partners distribution (OR = 1.78, 95% CI: 1.36-2.33), number of male sexual partners (OR = 2.11, 95% CI: 1.47-3.02), role of anal sex with men was receptive (OR = 2.54, 95% CI: 1.25-5.13) and versatile (OR = 2.34, 95% CI: 1.31-4.19) and non-steady sex partners (OR = 2.14, 95% CI: 1.56-2.93) were risk factors for HIV infection, while monthly income (OR = 0.68, 95% CI: 0.57-0.82), education level (OR = 0.79, 95% CI: 0.66-0.95), frequency of condom use (OR = 0.53, 95% CI: 0.35-0.81) and number of oral sex partners (OR = 0.35, 95% CI: 0.24-0.51) in the past 6 months were protective factors for HIV infection. CONCLUSION: Risk behaviors were common in MSM, and urgent need for targeted and comprehensive interventions to reduce risky sexual behaviour and to prevent HIV infection in MSM.


Asunto(s)
Infecciones por VIH , Minorías Sexuales y de Género , Masculino , Humanos , Adulto , Niño , Estudios Transversales , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Conducta Sexual , Factores de Riesgo , China/epidemiología
15.
ACS Biomater Sci Eng ; 9(8): 4462-4496, 2023 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-37470754

RESUMEN

The craniofacial region is composed of 23 bones, which provide crucial function in keeping the normal position of brain and eyeballs, aesthetics of the craniofacial complex, facial movements, and visual function. Given the complex geometry and architecture, craniofacial bone defects not only affect the normal craniofacial structure but also may result in severe craniofacial dysfunction. Therefore, the exploration of rapid, precise, and effective reconstruction of craniofacial bone defects is urgent. Recently, developments in advanced bone tissue engineering bring new hope for the ideal reconstruction of the craniofacial bone defects. This report, presenting a first-time comprehensive review of recent advances of biomaterials in craniofacial bone tissue engineering, overviews the modification of traditional biomaterials and development of advanced biomaterials applying to craniofacial reconstruction. Challenges and perspectives of biomaterial development in craniofacial fields are discussed in the end.


Asunto(s)
Huesos Faciales , Procedimientos de Cirugía Plástica , Huesos Faciales/cirugía , Materiales Biocompatibles/uso terapéutico , Ingeniería de Tejidos
17.
Science ; 381(6654): 181-186, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37319246

RESUMEN

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.

18.
Materials (Basel) ; 16(12)2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37374459

RESUMEN

In the context of ZnO nanorods (NRs) grown on Si and indium tin oxide (ITO) substrates, this study aimed to compare their degradation effect on methylene blue (MB) at different concentrations. The synthesis process was carried out at a temperature of 100 °C for 3 h. After the synthesis of ZnO NRs, their crystallization was analyzed using X-ray diffraction (XRD) patterns. The XRD patterns and top-view SEM observations demonstrate variations in synthesized ZnO NRs when different substrates were used. Furthermore, cross-sectional observations reveal that ZnO NRs synthesized on an ITO substrate exhibited a slower growth rate compared to those synthesized on a Si substrate. The as-grown ZnO NRs synthesized on the Si and ITO substrates exhibited average diameters of 110 ± 40 nm and 120 ± 32 nm and average lengths of 1210 ± 55 nm and 960 ± 58 nm, respectively. The reasons behind this discrepancy are investigated and discussed. Finally, synthesized ZnO NRs on both substrates were utilized to assess their degradation effect on methylene blue (MB). Photoluminescence spectra and X-ray photoelectron spectroscopy were employed to analyze the quantities of various defects of synthesized ZnO NRs. The effect of MB degradation after 325 nm UV irradiation for different durations can be evaluated using the Beer-Lambert law, specifically by analyzing the 665 nm peak in the transmittance spectrum of MB solutions with different concentrations. Our findings reveal that ZnO NRs synthesized on an ITO substrate exhibited a higher degradation effect on MB, with a rate of 59.5%, compared to NRs synthesized on a Si substrate, which had a rate of 73.7%. The reasons behind this outcome, elucidating the factors contributing to the enhanced degradation effect are discussed and proposed.

19.
Adv Sci (Weinh) ; 10(25): e2302747, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37379237

RESUMEN

Retinal degeneration, characterized by the progressive loss of retinal neurons, is the leading cause of incurable visual impairment. Retinal progenitor cells (RPCs)-based transplantation can facilitate sight restoration, but the clinical efficacy of this process is compromised by the imprecise neurogenic differentiation of RPCs and undermining function of transplanted cells surrounded by severely oxidative retinal lesions. Here, it is shown that ultrathin niobium carbide (Nb2 C) MXene enables performance enhancement of RPCs for retinal regeneration. Nb2 C MXene with moderate photothermal effect markedly improves retinal neuronal differentiation of RPCs by activating intracellular signaling, in addition to the highly effective RPC protection by scavenging free radicals concurrently, which has been solidly evidenced by the comprehensive biomedical assessments and theoretical calculations. A dramatically increased neuronal differentiation is observed upon subretinal transplantation of MXene-assisted RPCs into the typical retinal degeneration 10 (rd10) mice, thereby contributing to the efficient restoration of retinal architecture and visual function. The dual-intrinsic function of MXene synergistically aids RPC transplantation, which represents an intriguing paradigm in vision-restoration research filed, and will broaden the multifunctionality horizon of nanomedicine.


Asunto(s)
Degeneración Retiniana , Ratones , Animales , Degeneración Retiniana/terapia , Retina , Células Madre , Trasplante de Células
20.
Sci Total Environ ; 889: 163983, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37201813

RESUMEN

Marine debris comprising single-use plastic products (SUPs) is ubiquitous in Asian coastal waters, but there is little information on the types of polymers and the concentrations of plastic additives such waste products contain. In this study, 413 SUPs randomly collected from 4 Asian countries between 2020 and 2021 were analyzed to obtain specific polymer and organic additive profiles. Polyethylene (PE), coupled with external polymers, was prominent in the inside of the SUPs, whereas polypropylene (PP) and polyethylene terephthalate (PET) were prevalent in both the insides and outsides of the SUPs. The use of different polymers in the insides and outsides of PE SUPs implies specific and complicated recycling systems are required to maintain the purity of the products. Phthalate plasticizers including dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DiBP), dibutyl phthalate (DBP), and di(2-ethylhexyl) phthalate (DEHP), and the antioxidant butylated hydroxytoluene (BHT) were prevalent in the SUPs (n = 68). High concentrations of DEHP were detected in PE bags from Myanmar (820,000 ng/g) and Indonesia (420,000 ng/g), which were an order of magnitude greater than the concentrations in PE bags collected in Japan. SUPs containing high concentrations of organic additives may be the primary source of harmful chemicals in the environment, and should be responsible for their ubiquitous distribution in ecosystems.


Asunto(s)
Dietilhexil Ftalato , Ácidos Ftálicos , Polímeros , Japón , Indonesia , Mianmar , Tailandia , Ecosistema , Plásticos , Dibutil Ftalato , Polietileno
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