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1.
Int J Mol Sci ; 25(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38731861

RESUMO

The expression of polysialic acid (polySia) on the neuronal cell adhesion molecule (NCAM) is called NCAM-polysialylation, which is strongly related to the migration and invasion of tumor cells and aggressive clinical status. Thus, it is important to select a proper drug to block tumor cell migration during clinical treatment. In this study, we proposed that lactoferrin (LFcinB11) may be a better candidate for inhibiting NCAM polysialylation when compared with CMP and low-molecular-weight heparin (LMWH), which were determined based on our NMR studies. Furthermore, neutrophil extracellular traps (NETs) represent the most dramatic stage in the cell death process, and the release of NETs is related to the pathogenesis of autoimmune and inflammatory disorders, with proposed involvement in glomerulonephritis, chronic lung disease, sepsis, and vascular disorders. In this study, the molecular mechanisms involved in the inhibition of NET release using LFcinB11 as an inhibitor were also determined. Based on these results, LFcinB11 is proposed as being a bifunctional inhibitor for inhibiting both NCAM polysialylation and the release of NETs.


Assuntos
Armadilhas Extracelulares , Lactoferrina , Moléculas de Adesão de Célula Nervosa , Ácidos Siálicos , Lactoferrina/farmacologia , Lactoferrina/metabolismo , Humanos , Armadilhas Extracelulares/metabolismo , Armadilhas Extracelulares/efeitos dos fármacos , Moléculas de Adesão de Célula Nervosa/metabolismo , Ácidos Siálicos/metabolismo , Neutrófilos/metabolismo , Neutrófilos/efeitos dos fármacos , Heparina de Baixo Peso Molecular/farmacologia
2.
Ying Yong Sheng Tai Xue Bao ; 35(3): 769-779, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38646765

RESUMO

Exploring the correlations between ecosystem service value (ESV) and landscape ecological risk and the driving factors of their spatial variations is crucial for maintaining regional ecological security and promoting sustainable human well-being. We carried out a grid resampling size of 5 km×5 km assessment units of Jilin Pro-vince based on the remote sensing monitoring data of land use in 2000, 2005, 2010, 2015, and 2020. We quantitatively evaluated the landscape ecological risk and ESV, and analyzed their spatial-temporal variations. Employing bivariate spatial autocorrelation analysis and the geographical detector models, we examined the correlation between the landscape ecological risk and ESV and explored the driving factors for their spatial variations. The results showed that ESV in Jilin Province decreased from 385.895 billion yuan to 378.211 billion yuan during 2000-2020. The eastern region was dominated by extremely low risk, medium risk, and low risk areas. In contrast, the western region was mainly composed of extremely high risk and high risk areas. There was a significant negative correlation and spatial negative correlation between landscape ecological risk and ESV in Jilin Province. Human activity and land use type were the important driving factors for spatial differentiation in both landscape ecological risk and ESV. Our findings suggested that scientific land use regulation and appropriate control of human activities are critically needed to optimize Jilin Province's ecological environment.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Monitoramento Ambiental , China , Monitoramento Ambiental/métodos , Tecnologia de Sensoriamento Remoto , Medição de Risco , Ecologia , Análise Espacial , Atividades Humanas
3.
Cell Death Discov ; 10(1): 167, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589400

RESUMO

The neurotoxic α-synuclein (α-syn) oligomers play an important role in the occurrence and development of Parkinson's disease (PD), but the factors affecting α-syn generation and neurotoxicity remain unclear. We here first found that thrombomodulin (TM) significantly decreased in the plasma of PD patients and brains of A53T α-syn mice, and the increased TM in primary neurons reduced α-syn generation by inhibiting transcription factor p-c-jun production through Erk1/2 signaling pathway. Moreover, TM decreased α-syn neurotoxicity by reducing the levels of oxidative stress and inhibiting PAR1-p53-Bax signaling pathway. In contrast, TM downregulation increased the expression and neurotoxicity of α-syn in primary neurons. When TM plasmids were specifically delivered to neurons in the brains of A53T α-syn mice by adeno-associated virus (AAV), TM significantly reduced α-syn expression and deposition, and ameliorated the neuronal apoptosis, oxidative stress, gliosis and motor deficits in the mouse models, whereas TM knockdown exacerbated these neuropathology and motor dysfunction. Our present findings demonstrate that TM plays a neuroprotective role in PD pathology and symptoms, and it could be a novel therapeutic target in efforts to combat PD. Schematic representation of signaling pathways of TM involved in the expression and neurotoxicity of α-syn. A TM decreased RAGE, and resulting in the lowered production of p-Erk1/2 and p-c-Jun, and finally reduce α-syn generation. α-syn oligomers which formed from monomers increase the expression of p-p38, p53, C-caspase9, C-caspase3 and Bax, decrease the level of Bcl-2, cause mitochondrial damage and lead to oxidative stress, thus inducing neuronal apoptosis. TM can reduce intracellular oxidative stress and inhibit p53-Bax signaling by activating APC and PAR-1. B The binding of α-syn oligomers to TLR4 may induce the expression of IL-1ß, which is subsequently secreted into the extracellular space. This secreted IL-1ß then binds to its receptor, prompting p65 to translocate from the cytoplasm into the nucleus. This translocation downregulates the expression of KLF2, ultimately leading to the suppression of TM expression. By Figdraw.

4.
Tob Induc Dis ; 222024.
Artigo em Inglês | MEDLINE | ID: mdl-38638420

RESUMO

INTRODUCTION: Acupuncture and related acupoint therapies have been widely used for smoking cessation. Some relevant systematic reviews (SRs) have been published. There is a need to summarize and update the evidence to inform practice and decision-making. METHODS: Eight databases were searched from their inception to December 2023. SRs, any randomized controlled trials (RCTs) comparing acupuncture therapies with sham acupuncture, pharmacotherapy, behavioral therapy, or no treatment, were included. The primary outcome was the abstinence rate. AMSTAR-2 was employed to assess the quality of SRs. An updated meta-analysis was conducted based on SRs and RCTs. Data were synthesized using risk ratios (RR) with 95% confidence intervals (CIs). The GRADE approach was employed to assess the certainty of the updated evidence. RESULTS: Thirteen SRs and 20 RCTs outside of the SRs were identified. The SRs were of low or very low quality by AMSTAR-2. Sixteen (80%) RCTs were at high risk of performance bias. Eight acupuncture and related acupoint therapies were involved. The short-term (≤6 months) abstinence rate outcome was summarized as follows. Most SRs suggested that filiform needle acupuncture or acupressure had a better effect than sham acupuncture, but the findings were inconsistent. The updated meta-analysis also suggested that filiform needle acupuncture was more effective than sham acupuncture (RR=1.44; 95% CI: 1.02-2.02; I2 = 66%; low certainty; 9 RCTs, n=1358). Filiform needle acupuncture combined with acupressure was comparable to nicotine patches (RR=0.99; 95% CI: 0.74-1.32; low certainty; 6 RCTs, n= 524). Acupressure was superior to counseling (RR=1.46; 95% CI: 1.14-1.87; I2=5%; low certainty; 8 RCTs, n=595). No serious adverse events were reported in these SRs or RCTs. CONCLUSIONS: Low certainty evidence suggests that filiform needle acupuncture and auricular acupressure appear to be safe and effective in achieving short-term smoking cessation. However, long-term follow-up data are needed.

5.
Acta Neuropathol Commun ; 12(1): 66, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654316

RESUMO

The elderly frequently present impaired blood-brain barrier which is closely associated with various neurodegenerative diseases. However, how the albumin, the most abundant protein in the plasma, leaking through the disrupted BBB, contributes to the neuropathology remains poorly understood. We here demonstrated that mouse serum albumin-activated microglia induced astrocytes to A1 phenotype to remarkably increase levels of Elovl1, an astrocytic synthase for very long-chain saturated fatty acids, significantly promoting VLSFAs secretion and causing neuronal lippoapoptosis through endoplasmic reticulum stress response pathway. Moreover, MSA-activated microglia triggered remarkable tau phosphorylation at multiple sites through NLRP3 inflammasome pathway. Intracerebroventricular injection of MSA into the brains of C57BL/6J mice to a similar concentration as in patient brains induced neuronal apoptosis, neuroinflammation, increased tau phosphorylation, and decreased the spatial learning and memory abilities, while Elovl1 knockdown significantly prevented the deleterious effect of MSA. Overall, our study here revealed that MSA induced tau phosphorylation and neuron apoptosis based on MSA-activated microglia and astrocytes, respectively, showing the critical roles of MSA in initiating the occurrence of tauopathies and cognitive decline, and providing potential therapeutic targets for MSA-induced neuropathology in multiple neurodegenerative disorders.


Assuntos
Apoptose , Camundongos Endogâmicos C57BL , Neurônios , Albumina Sérica , Tauopatias , Animais , Humanos , Masculino , Camundongos , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Astrócitos/metabolismo , Astrócitos/patologia , Astrócitos/efeitos dos fármacos , Elongases de Ácidos Graxos/metabolismo , Microglia/metabolismo , Microglia/efeitos dos fármacos , Microglia/patologia , Neurônios/metabolismo , Neurônios/patologia , Neurônios/efeitos dos fármacos , Albumina Sérica/metabolismo , Albumina Sérica/farmacologia , Proteínas tau/metabolismo , Tauopatias/patologia , Tauopatias/metabolismo
6.
Nat Mater ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664497

RESUMO

In situ tailoring of two-dimensional materials' phases under external stimulus facilitates the manipulation of their properties for electronic, quantum and energy applications. However, current methods are mainly limited to the transitions among phases with unchanged chemical stoichiometry. Here we propose on-device phase engineering that allows us to realize various lattice phases with distinct chemical stoichiometries. Using palladium and selenide as a model system, we show that a PdSe2 channel with prepatterned Pd electrodes can be transformed into Pd17Se15 and Pd4Se by thermally tailoring the chemical composition ratio of the channel. Different phase configurations can be obtained by precisely controlling the thickness and spacing of the electrodes. The device can be thus engineered to implement versatile functions in situ, such as exhibiting superconducting behaviour and achieving ultralow-contact resistance, as well as customizing the synthesis of electrocatalysts. The proposed on-device phase engineering approach exhibits a universal mechanism and can be expanded to 29 element combinations between a metal and chalcogen. Our work highlights on-device phase engineering as a promising research approach through which to exploit fundamental properties as well as their applications.

7.
Phytomedicine ; 127: 155467, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38447360

RESUMO

The death and disability caused by myocardial infarction is a health problem that needs to be addressed worldwide, and poor cardiac repair and fibrosis after myocardial infarction seriously affect patient recovery. Postmyocardial infarction repair by M2 macrophages is of great significance for ventricular remodeling. Quercitrin (Que) is a common flavonoid in fruits and vegetables that has antioxidant, anti-inflammatory, antitumor and other effects, but whether it has a role in the treatment of myocardial infarction is unclear. In this study, we constructed a mouse myocardial infarction model and administered Que. We found through cardiac ultrasound that Que administration improved cardiac ejection fraction and reduced ventricular remodeling. Staining of heart sections and detection of fibrosis marker protein levels revealed that Que administration slowed fibrosis after myocardial infarction. Flow cytometry showed that the proportion of M2 macrophages in the mouse heart was increased and that the expression levels of M2 macrophage markers were increased in the Que-treated group. Finally, we identified by metabolomics that Que reduces glycolysis, increases aerobic phosphorylation, and alters arginine metabolic pathways, polarizing macrophages toward the M2 phenotype. Our research lays the foundation for the future application of Que in myocardial infarction and other cardiovascular diseases.


Assuntos
Infarto do Miocárdio , Quercetina/análogos & derivados , Remodelação Ventricular , Camundongos , Animais , Humanos , Reprogramação Metabólica , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/patologia , Macrófagos/metabolismo , Fibrose , Miocárdio/metabolismo
8.
Small ; : e2311056, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38377262

RESUMO

The poor efficiency and low immunogenicity of photodynamic therapy (PDT), and the immunosuppressive tumor microenvironment (ITM) lead to tumor recurrence and metastasis. In this work, TCPP-TER -Zn@RSV nanosheets (TZR NSs) that co-assembled from the endoplasmic reticulum (ER)-targeting photosensitizer TCPP-TER -Zn nanosheets (TZ NSs for short) and the autophagy promoting and indoleamine-(2, 3)-dioxygenase (IDO) inhibitor-like resveratrol (RSV) are fabricated to enhance antitumor PDT. TZR NSs exhibit improved therapeutic efficiency and amplified immunogenic cancer cell death (ICD) by ER targeting PDT and ER autophagy promotion. TZR NSs reversed the ITM with an increase of CD8+ T cells and reduce of immunosuppressive Foxp3 regulatory T cells, which effectively burst antitumor immunity thus clearing residual tumor cells. The ER-targeting TZR NSs developed in this paper presents a simple but valuable reference for high-efficiency tumor photodynamic immunotherapy.

9.
Nat Commun ; 15(1): 1129, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321042

RESUMO

The spin Hall effect (SHE) allows efficient generation of spin polarization or spin current through charge current and plays a crucial role in the development of spintronics. While SHE typically occurs in non-magnetic materials and is time-reversal even, exploring time-reversal-odd (T-odd) SHE, which couples SHE to magnetization in ferromagnetic materials, offers a new charge-spin conversion mechanism with new functionalities. Here, we report the observation of giant T-odd SHE in Fe3GeTe2/MoTe2 van der Waals heterostructure, representing a previously unidentified interfacial magnetic spin Hall effect (interfacial-MSHE). Through rigorous symmetry analysis and theoretical calculations, we attribute the interfacial-MSHE to a symmetry-breaking induced spin current dipole at the vdW interface. Furthermore, we show that this linear effect can be used for implementing multiply-accumulate operations and binary convolutional neural networks with cascaded multi-terminal devices. Our findings uncover an interfacial T-odd charge-spin conversion mechanism with promising potential for energy-efficient in-memory computing.

10.
J Control Release ; 367: 248-264, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272398

RESUMO

As a potential treatment strategy for low immunogenic triple negative breast cancer (TNBC), photodynamic therapy (PDT) induced antitumor immunotherapy is greatly limited by the immunosuppressive tumor microenvironment (ITM), especially the M2 phenotype tumor-associated macrophages (TAMs). The balance of arginine metabolism plays an important role in TAMs polarization. Herein, a multifunctional nanoplatform (defined as HN-HFPA) was employed to burst the anti-tumor immunity of TNBC post PDT by reeducating TAMs through interfering the TAMs-associated arginine metabolism. The L-arginine (L-Arg) was loaded in the hollow cavity of HN-HFPA, which could not only generate nitric oxide (NO) for tumor therapy, but also serve as a substrate of arginine metabolism pathway. As an inhibitor of arginases-1 (Arg-1) of M2 TAMs, L-norvaline (L-Nor) was modified to the hyaluronic acid (HA), and coated in the surface of HFPA. After degradation of HA by hyaluronidase in tumor tissue and GSH-mediated disintegration, HN-HFPA depleted intracellular GSH, produced remarkable reactive oxygen species (ROS) under light irradiation and released L-Arg to generate NO, which induced tumor immunogenic cell death (ICD). Real-time ultrasound imaging of tumor was realized taking advantage of the gas feature of NO. The L-Nor suppressed the Arg-1 overexpressed in M2, which skewed the balance of arginine metabolism and reversed the ITM with increased ratios of M1 and CD8+ T cells, finally resulted in amplified antitumor immune response and apparent tumor metastasis inhibition. This study remodeled ITM to strengthen immune response post PDT, which provided a promising treatment strategy for TNBC.


Assuntos
Nanopartículas , Neoplasias , Neoplasias de Mama Triplo Negativas , Humanos , Linfócitos T CD8-Positivos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Macrófagos Associados a Tumor , Imunoterapia , Arginina , Ácido Hialurônico , Imunossupressores , Óxido Nítrico , Microambiente Tumoral , Linhagem Celular Tumoral
11.
Mol Biol Rep ; 51(1): 55, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38165476

RESUMO

BACKGROUND: Reverse transcription quantitative polymerase chain reaction (RT-qPCR) can accurately detect relative gene expression levels in biological samples. However, widely used reference genes exhibit unstable expression under certain conditions. METHODS AND RESULTS: Here, we compared the expression stability of eight reference genes (RPLP0, RPS18, RPL13, EEF1A1, ß-actin, GAPDH, HPRT1, and TUBB) commonly used in liproxstatin-1 (Lip-1)-treated K562 cells using RNA-sequencing and RT-qPCR. The expression of EEF1A1, ACTB, GAPDH, HPRT1, and TUBB was considerably lower in cells treated with 20 µM Lip-1 than in the control, and GAPDH also showed significant downregulation in the 10 µM Lip-1 group. Meanwhile, when we used geNorm, NormFinder, and BestKeeper to compare expression stability, we found that GAPDH and HPRT1 were the most unstable reference genes among all those tested. Stability analysis yielded very similar results when geNorm or BestKeeper was used but not when NormFinder was used. Specifically, geNorm and BestKeeper identified RPL13 and RPLP0 as the most stable genes under 20 µM Lip-1 treatment, whereas RPL13, EEF1A1, and TUBB were the most stable under 10 µM Lip-1 treatment. TUBB and EEF1A1 were the most stable genes in both treatment groups according to the results obtained using NormFinder. An assumed most stable gene was incorporated into each software to validate the accuracy. The results suggest that NormFinder is not an appropriate algorithm for this study. CONCLUSIONS: Stable reference genes were recognized using geNorm and BestKeeper but not NormFinder. Overall, RPL13 and RPLP0 were the most stable reference genes under 20 µM Lip-1 treatment, whereas RPL13, EEF1A1, and TUBB were the most stable genes under 10 µM Lip-1 treatment.


Assuntos
Actinas , Leucemia , Humanos , Células K562 , Sequência de Bases , Análise de Sequência de RNA , Hipoxantina Fosforribosiltransferase , Proteínas de Neoplasias , Proteínas Ribossômicas
12.
DNA Res ; 31(1)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38245835

RESUMO

Plant terrestrialization (i.e. the transition to a terrestrial environment) is a significant evolutionary event that has been intensively studied. While certain plant lineages, particularly in angiosperms, have re-adapted to freshwater habitats after colonizing terrene, however, the molecular mechanism of the terrestrial-freshwater (T-F) transition remains limited. Here, the basal monocot Araceae was selected as the study object to explore the T-F transition adaptation mechanism by comparative genomic analysis. Our findings revealed that the substitution rates significantly increased in the lineage of freshwater Araceae, which may promote their adaptation to the freshwater habitat. Additionally, 20 gene sets across all four freshwater species displayed signs of positive selection contributing to tissue development and defense responses in freshwater plants. Comparative synteny analysis showed that genes specific to submerged plants were enriched in cellular respiration and photosynthesis. In contrast, floating plants were involved in regulating gene expression, suggesting that gene and genome duplications may provide the original material for plants to adapt to the freshwater environment. Our study provides valuable insights into the genomic aspects of the transition from terrestrial to aquatic environments in Araceae, laying the groundwork for future research in the angiosperm.


Assuntos
Araceae , Evolução Biológica , Genoma , Água Doce , Plantas , Cromossomos , Filogenia
13.
Acta Pharmacol Sin ; 45(3): 531-544, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37919475

RESUMO

Cardiac inflammation contributes to heart failure (HF) induced by isoproterenol (ISO) through activating ß-adrenergic receptors (ß-AR). Recent evidence shows that myeloid differentiation factor 2 (MD2), a key protein in endotoxin-induced inflammation, mediates inflammatory heart diseases. In this study, we investigated the role of MD2 in ISO-ß-AR-induced heart injuries and HF. Mice were infused with ISO (30 mg·kg-1·d-1) via osmotic mini-pumps for 2 weeks. We showed that MD2 in cardiomyocytes and cardiac macrophages was significantly increased and activated in the heart tissues of ISO-challenged mice. Either MD2 knockout or administration of MD2 inhibitor L6H21 (10 mg/kg every 2 days, i.g.) could prevent mouse hearts from ISO-induced inflammation, remodelling and dysfunction. Bone marrow transplantation study revealed that both cardiomyocyte MD2 and bone marrow-derived macrophage MD2 contributed to ISO-induced cardiac inflammation and injuries. In ISO-treated H9c2 cardiomyocyte-like cells, neonatal rat primary cardiomyocytes and primary mouse peritoneal macrophages, MD2 knockout or pre-treatment with L6H21 (10 µM) alleviated ISO-induced inflammatory responses, and the conditioned medium from ISO-challenged macrophages promoted the hypertrophy and fibrosis in cardiomyocytes and fibroblasts. We demonstrated that ISO induced MD2 activation in cardiomyocytes via ß1-AR-cAMP-PKA-ROS signalling axis, and induced inflammatory responses in macrophages via ß2-AR-cAMP-PKA-ROS axis. This study identifies MD2 as a key inflammatory mediator and a promising therapeutic target for ISO-induced heart failure.


Assuntos
Insuficiência Cardíaca , Miócitos Cardíacos , Ratos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Isoproterenol/toxicidade , Receptores Adrenérgicos beta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Macrófagos/metabolismo
14.
J Oncol Pharm Pract ; : 10781552231216104, 2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38043937

RESUMO

INTRODUCTION: Immune checkpoint inhibitors can cause immune-related toxicity in various systems, with myocarditis being the most severe and life-threatening manifestation. This report presents a case in which myocarditis developed following administration of programmed cell death protein-1 (PD-1) inhibitors therapy. We describe the diagnosis and treatment of this patient in detail. CASE REPORT: We present the case of a 59-year-old female diagnosed with post-operative esophageal cancer and hepatic metastases. The patient underwent second-line treatment with domestically-made PD-1 inhibitor, camrelizumab, in combination with paclitaxel (albumin-bound) and carboplatin for two cycles. During the course of treatment, an electrocardiogram (ECG) revealed ST segment elevation in leads II, III, aVF, V2, V3, and V4, along with T wave changes in leads I and aVL. Laboratory examinations showed abnormal levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponin T (cTnT). Despite the absence of clinical symptoms, the patient was routinely hospitalized three weeks later. Based on the findings from the ECG, cardiac biomarkers, echocardiography, echocardiogram, cardiac magnetic resonance, and angiography, she was diagnosed with immune-checkpoint-inhibitors-related myocarditis. MANAGEMENT AND OUTCOME: The patient received immunoglobulin (0.5 g/kg/day) and was initially given methylprednisolone (1000 mg/day). Methylprednisolone was gradually reduced to 40 mg/day in 2 weeks. During this time, the levels of biomarkers indicative of myocardial injury also exhibited a simultaneous decline. DISCUSSION: This case highlights the importance of early detection and prompt intervention, including initiating appropriate steroid therapy and discontinuing of immune checkpoint inhibitors. Such measures can effectively prevent morbidity and mortality, ultimately leading to an improved prognosis.

15.
Nano Lett ; 23(21): 9928-9935, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37862098

RESUMO

Memristors have attracted considerable attention in the past decade, holding great promise for future neuromorphic computing. However, the intrinsic poor stability and large device variability remain key limitations for practical application. Here, we report a simple method to directly visualize the origin of poor stability. By mechanically removing the top electrodes of memristors operated at different states (such as SET or RESET), the memristive layer could be exposed and directly characterized through conductive atomic force microscopy, providing two-dimensional area information within memristors. Based on this technique, we observed the existence of multiple conducting filaments during the formation process and built up a physical model between filament numbers and the cycle-to-cycle variation. Furthermore, by improving the interface quality through the van der Waals top electrode, we could reduce the filament number down to a single filament during all switching cycles, leading to much controlled switching behavior and reliable device operation.

16.
J Phys Chem A ; 127(41): 8566-8573, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37796447

RESUMO

Improving the energy efficiency of electrocatalytic reduction of CO2 requires tuning of redox properties of electrocatalysts to match redox potentials of the substrate. Recently, we introduced nanographenes as ligands for metal complexes for such purposes by taking advantage of size-dependent properties of the conjugated systems. Here, we use computations to investigate the structure dependence of the electrocatalysis at Re(diimine)(CO)3Cl complexes with nanographene ligands that contain a polycyclic aromatic hydrocarbon moiety through a pyrazinyl linkage. We show that the reduction potentials of the complexes depend not only on conjugation size but also on shape and geometry of the ligands, revealing another parameter in tuning the redox properties of the electrocatalysts. In addition, our work reveals a compromise between reduction potentials and activation of this class of electrocatalysts.

17.
Sci Adv ; 9(39): eadi4083, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37774015

RESUMO

Parallel perception of visual motion is of crucial significance to the development of an intelligent machine vision system. However, implementing in-sensor parallel visual motion perception using conventional complementary metal-oxide semiconductor technology is challenging, because the temporal and spatial information embedded in motion cannot be simultaneously encoded and perceived at the sensory level. Here, we demonstrate the parallel perception of diverse motion modes at the sensor level by exploiting light-tunable memory matrix in a van der Waals (vdW) heterostructure array. The optoelectronic characteristics of gate-tunable photoconductivity and light-tunable memory matrix enable devices in the array to realize simultaneous encoding and processing of incoming spatiotemporal light pattern. Furthermore, we implement a visual motion perceptron with the array capable of deciphering multiple motion parameters in parallel, including direction, velocity, acceleration, and angular velocity. Our work opens up a promising venue for the realization of an intelligent machine vision system based on in-sensor motion perception.

18.
Front Immunol ; 14: 1193081, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37680624

RESUMO

Yolk sac-derived microglia and peripheral monocyte-derived macrophages play a key role during Parkinson's disease (PD) progression. However, the regulatory mechanism of microglia/macrophage activation and function in PD pathogenesis remains unclear. Recombination signal-binding protein Jκ (RBP-J)-mediated Notch signaling regulates macrophage development and activation. In this study, with an 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) hydrochloride-induced acute murine PD model, we found that Notch signaling was activated in amoeboid microglia accompanied by a decrease in tyrosine hydroxylase (TH)-positive neurons. Furthermore, using myeloid-specific RBP-J knockout (RBP-JcKO) mice combined with a PD model, our results showed that myeloid-specific disruption of RBP-J alleviated dopaminergic neurodegeneration and improved locomotor activity. Fluorescence-activated cell sorting (FACS) analysis showed that the number of infiltrated inflammatory macrophages and activated major histocompatibility complex (MHC) II+ microglia decreased in RBP-JcKO mice compared with control mice. Moreover, to block monocyte recruitment by using chemokine (C-C motif) receptor 2 (CCR2) knockout mice, the effect of RBP-J deficiency on dopaminergic neurodegeneration was not affected, indicating that Notch signaling might regulate neuroinflammation independent of CCR2+ monocyte infiltration. Notably, when microglia were depleted with the PLX5622 formulated diet, we found that myeloid-specific RBP-J knockout resulted in more TH+ neurons and fewer activated microglia. Ex vitro experiments demonstrated that RBP-J deficiency in microglia might reduce inflammatory factor secretion, TH+ neuron apoptosis, and p65 nuclear translocation. Collectively, our study first revealed that RBP-J-mediated Notch signaling might participate in PD progression by mainly regulating microglia activation through nuclear factor kappa-B (NF-κB) signaling.


Assuntos
NF-kappa B , Doença de Parkinson , Animais , Camundongos , Microglia , Ativação de Macrófagos , Transdução de Sinais , Dopamina
19.
J Enzyme Inhib Med Chem ; 38(1): 2248411, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37615033

RESUMO

The overexpression of polysialic acid (polySia) on neural cell adhesion molecules (NCAM) promotes hypersialylation, and thus benefits cancer cell migration and invasion. It has been proposed that the binding between the polysialyltransferase domain (PSTD) and CMP-Sia needs to be inhibited in order to block the effects of hypersialylation. In this study, CMP was confirmed to be a competitive inhibitor of polysialyltransferases (polySTs) in the presence of CMP-Sia and triSia (oligosialic acid trimer) based on the interactional features between molecules. The further NMR analysis suggested that polysialylation could be partially inhibited when CMP-Sia and polySia co-exist in solution. In addition, an unexpecting finding is that CMP-Sia plays a role in reducing the gathering extent of polySia chains on the PSTD, and may benefit for the inhibition of polysialylation. The findings in this study may provide new insight into the optimal design of the drug and inhibitor for cancer treatment.


Assuntos
Movimento Celular
20.
Radiat Oncol ; 18(1): 129, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542246

RESUMO

PURPOSE: In this study, we aimed to compare the radiation-induced hepatic toxicity (RIHT) outcomes of radiotherapy (RT) plus antibodies against programmed cell death protein 1 (anti-PD1) versus RT alone in patients with hepatocellular carcinoma (HCC), evaluate prognostic factors of non-classic radiation-induced liver disease (ncRILD), and establish a nomogram for predicting the probability of ncRILD. PATIENTS AND METHODS: Patients with unresectable HCC treated with RT and anti-PD1 (RT + PD1, n = 30) or RT alone (n = 66) were enrolled retrospectively. Patients (n = 30) in each group were placed in a matched cohort using propensity score matching (PSM). Treatment-related hepatotoxicity was evaluated and analyzed before and after PSM. The prognostic factors affecting ncRILD were identified by univariable logistic analysis and Spearman's rank test in the matched cohort to generate a nomogram. RESULTS: There were no differences in RIHT except for increased aspartate aminotransferase (AST) ≥ grade 1 and increased total bilirubin ≥ grade 1 between the two groups before PSM. After PSM, AST ≥ grade 1 occurred more frequently in the RT + PD1 group (p = 0.020), and there were no significant differences in other hepatotoxicity metrics between the two groups. In the matched cohort, V25, tumor number, age, and prothrombin time (PT) were the optimal prognostic factors for ncRILD modeling. A nomogram revealed a good predictive performance (area under the curve = 0.82). CONCLUSIONS: The incidence of RIHT in patients with HCC treated with RT + PD1 was acceptable and similar to that of RT treatment. The nomogram based on V25, tumor number, age, and PT robustly predicted the probability of ncRILD.


Assuntos
Carcinoma Hepatocelular , Doença Hepática Induzida por Substâncias e Drogas , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Receptor de Morte Celular Programada 1 , Pontuação de Propensão
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