Publications by authors named "Da Xu"

Guillain-Barré syndrome (GBS) is a heterogeneous disease, and it usually develops after an antecedent infection, while rare cases develop following a central nervous system disease. Given the indeterminacy of prodromal infection symptoms and the overlap of symptoms with other neurological disorders, a rigorous clinical and neurological examination in conjunction with history is necessary for early diagnosis and treatment of GBS. Here we present a rare case of GBS following acute ischemic stroke which was different from previous reports such as GBS following hemorrhagic stroke or head trauma.

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Programmable epigenome editors modify gene expression in mammalian cells by altering the local chromatin environment at target loci without inducing DNA breaks. However, the large size of CRISPR-based epigenome editors poses a challenge to their broad use in biomedical research and as future therapies. Here, we present Robust ENveloped Delivery of Epigenome-editor Ribonucleoproteins (RENDER) for transiently delivering programmable epigenetic repressors (CRISPRi, DNMT3A-3L-dCas9, CRISPRoff) and activator (TET1-dCas9) as ribonucleoprotein complexes into human cells to modulate gene expression.

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  • In eutrophic shallow lakes, increased temperatures lead to changes in surface sediment properties, affecting density and water content, particularly between 10 to 35 ℃.
  • During a one-month study, cyanobacterial blooms degraded in sediment caused flocculation and agglomeration of sediment particles, aided by high ratios of polysaccharides and proteins in extracellular substances.
  • Sediment with cyanobacterial blooms showed significant yield stress decay with temperature increases, and a critical shear stress threshold at 20 ℃ indicated easier sediment resuspension, emphasizing the need for careful sediment management in these environments.
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Aiming at the problem of overbrightness of the target simulator background for LED backlight panel illumination, a 5° aperture angle-matched collimated illumination method for the target simulator is proposed based on the study of the dark-state leakage of the LCD display device and the scattered stray light of the system. After simulation analysis the method can make the display contrast increase by 3.1 times and solve the problem of dark targets being drowned by the background bright light, which exists in the LED illumination target simulator.

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This study investigated the multiple correlations among spectral simulation units based on digital micromirror device (DMD) spectral simulation, which leads to the problem that conventional spectral simulation methods such as PID control exhibit a low fitting accuracy or long fitting time in the spectral simulation of various targets. In this paper, a method of stellar spectrum simulation based on back propagation neural network-based PID (BP-PID) control is proposed to achieve high efficiency and high precision simulation of various spectral targets. The topology of the BP neural network was constructed based on the spectral modulation model of a DMD stellar spectrum simulation system, and the algorithm of the BP-PID control was designed.

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Aiming at the problem that the error of multi-optical axis alignment is difficult to control in the simulation calibration test, a multi-optical axis dynamic compensation alignment method for the space environment simulation system is proposed. The effect of optical axis disturbance on the signal detection link was analyzed to obtain the alignment accuracy requirements, the optical axis alignment error compensation mechanism was established, the target simulation system with long pupil distance was designed, the alignment error transfer model based on topology structure was constructed, and the test prototype was built. The test results show that the static attitude alignment resolution is better than 3" and the position alignment resolution is better than 11µm.

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  • * The study analyzes a large sample of 128,822 patients to investigate how the duration and number of chronic diseases affect prognosis after a hip fracture.
  • * A novel cross-attention neural network is developed to improve prognosis predictions, highlighting the significance of chronic disease patterns for better clinical decision-making.
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  • Long-term head-down bedrest (HDBR) simulates weightlessness and negatively impacts the retina and cerebrovascular regulation in healthy males.
  • Participants experienced a decrease in retinal arteriolar diameter by day 8 and an increase in venular diameter by day 16, along with higher blood pressure and lower cerebral blood flow velocity during HDBR.
  • An anti-inflammatory/antioxidant cocktail did not reverse these vascular changes, suggesting it was ineffective in restoring normal microcirculation and cerebral blood flow.
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Background: Alzheimer's disease (AD) is a common elderly disorder characterized by cognitive decline. Endoplasmic reticulum (ER) stress has been implicated in various neurodegenerative diseases, including AD. Stem cell factor (SCF) performs its biological functions by binding to and activating receptor tyrosine kinase c-Kit.

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Background: Observational studies suggest that hypertension and epilepsy have a high co-occurrence, and antihypertensive medications may have impacts on the prevention and treatment of epilepsy. However, the directionality of causation between them is elusive.

Method: By leveraging genome-wide association studies (GWAS) summary data of each trait, we firstly performed bidirectional univariate Mendelian randomization (UVMR) to assess the strength and direction of the associations between pairs of traits, then multivariate MR (MVMR) was conducted to adjust for potential confounders in causalities.

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Inherently chiral eight-membered rings embedded in tetraphenylene derivatives and hetero-analogues exhibit unique properties and allow diverse applications. A conceptually viable and straightforward approach to these frameworks is [4+4] cycloaddition, which still remains elusive. Herein, we describe the stereoselective cross-[4+4] cycloaddition of quinone methides (QMs), leading to the formation of oxa-analogues of tetraphenylene with exceptional chemo-, diastereo-, and enantioselectivity.

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Iron death is a novel type of programmed cell death caused by excessive accumulation of iron-dependent lipid peroxidation products; however, the function of iron death during porcine oocyte maturation and embryo growth is poorly understood. This study was conducted to investigate the mechanism of ferric ammonium citrate (FAC) in regulating iron death in mature oocytes in vitro through the NRF2 signaling pathway, and subsequent embryonic development. The experiment was divided into four groups: 0 (control group), 2, 5, and 10 μM FAC.

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Disialoganglioside (GD2) is one of the most popular overexpressed antigens for tumor cell targeting. However, GD2-specific antibodies often show unintended targeting to GD2-expressing health-maintaining cells due to the comparable binding affinities both at physiological pH and in a slightly acidic tumor microenvironment (TME). In this work, an affinity-switchable zwitterionic PAMAM G5 dendrimer (G5-3S) is developed for selective binding to GD2 only in a slightly acidic TME.

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  • The study tracks halocarbon concentrations in the Yangtze River Delta region from 2018 to 2020, revealing an upward trend driven by both regulated and unregulated substances.
  • Dichloromethane and chloromethane are identified as the most prevalent halocarbons, with local emissions significantly influencing their levels.
  • The findings highlight significant health risks, particularly from chloroform and 1,2-dichloroethane surpassing safe thresholds, indicating a need for better control and reduction of halocarbon emissions.
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  • The study investigates how different long-term patterns of body mass index (BMI) impact the risk of developing hypertension in individuals over time.
  • It analyzed data from a significant cohort of children and adolescents in China, revealing three distinct BMI trajectories: low-increasing, moderate-increasing, and high-increasing.
  • The results indicated that higher BMI trajectories, particularly in males, were significantly associated with increased risk of hypertension, emphasizing the importance of maintaining a healthy BMI and lifestyle from a young age.
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Coupling direct air capture (DAC) with methane (CH) production is a potential strategy for fuel production from the air. Here, we report a hybrid electro-thermochemical device for direct CH production from air. The proposed device features the cogeneration of carbon dioxide (CO) and hydrogen (H) in a single compartment via a bipolar membrane electrodialysis module, avoiding a separate water electrolyzer, followed by a thermochemical methanation reaction to produce CH.

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Bile acid (BA) homeostasis is vital for various physiological processes, whereas its disruption underlies cholestasis. The farnesoid X receptor (FXR) is a master regulator of BA homeostasis via the ileal fibroblast growth factor (FGF)15/19 endocrine pathway, responding to postprandial or abnormal transintestinal BA flux. However, the de novo paracrine signal mediator of hepatic FXR, which governs the extent of BA synthesis within the liver in non-postprandial or intrahepatic cholestatic conditions, remains unknown.

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  • - The emergence of CRISPR technologies has revolutionized gene manipulation through innovations like epigenetic editing, which controls gene expression without altering DNA sequences or creating breaks in the genome.
  • - The CRISPRoff technology enables the establishment of repressive DNA and histone modifications at gene promoters, effectively silencing targeted genes in a way that is heritable through cell division.
  • - The article outlines protocols for delivering CRISPRoff via plasmid DNA and mRNA into various human cell types, while also offering evaluation methods for gene silencing and best practices for using CRISPRoff for gene perturbation.
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  • - Fluorescent nanodiamonds (FNDs) with nitrogen-vacancy centers are crucial for improving quantum photonics and imaging but face challenges in achieving effective integration into photonic devices.
  • - The researchers developed a method to integrate FNDs into a nanofocusing device using plasmonic-enhanced optical trapping, which significantly boosts the emission rate and directs light more efficiently into the waveguide.
  • - Their technique achieved a transfer efficiency figure-of-merit of ∼3000, marking a major advancement in the integration of quantum emitters for future quantum imaging and communication technologies.
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  • - The study evaluates the effectiveness and safety of a new treatment combining hepatic arterial infusion chemotherapy (HAIC) with fruquintinib and tislelizumab for patients with microsatellite stable colorectal cancer liver metastasis (MSS-CRCLM) who have not responded to previous therapies.
  • - Out of 45 patients treated from February 2021 to June 2023, the results showed a 42.2% objective response rate and a 15.3-month median overall survival, with manageable adverse effects.
  • - The findings suggest that this combination therapy could serve as a promising alternative for patients with MSS-CRCLM who have limited options after failing multiple treatments.
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Human ABC transporters ABCD1-3 are all localized on the peroxisomal membrane and participate in the β-oxidation of fatty acyl-CoAs, but they differ from each other in substrate specificity. The transport of branched-chain fatty acids from cytosol to peroxisome is specifically driven by ABCD3, dysfunction of which causes severe liver diseases such as hepatosplenomegaly. Here we report two cryogenic electron microscopy (cryo-EM) structures of ABCD3 bound to phytanoyl-CoA and ATP at resolutions of 2.

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Background: The adverse effects of a Western diet on obesity and diabetes among reproductive-aged women pose a significant threat to the cardiovascular health of their offspring. Given the crucial role of glutathione metabolism and glutathione-related antioxidant defense systems in cardiovascular diseases through scavenging ROS and maintaining redox homeostasis, further exploration of their specific influence is imperative to develop therapeutic strategies for cardiomyopathy induced by a maternal Western diet.

Methods: We developed a prenatal maternal Western diet exposure model in C57/B6 mice to investigate cardiac morphology and function through histological analysis and echocardiography.

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Objectives: This study aimed to investigate the epidemiological and drug resistance (DR) characteristics of extrapulmonary tuberculosis (EPTB) in South-Central China.

Methods: EPTB inpatients who were culture-positive for were retrospectively included in a study at a provincial TB hospital in Hunan, a province in South-Central China, from January 2013 to December 2021. Demographic, clinical, and drug susceptibility data were retrieved from TB treatment records.

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