Publications by authors named "Xiao-meng Shi"

Article Synopsis
  • Neuroimaging studies reveal structural and functional brain disruptions in OCD patients, but their mechanisms are still unclear.
  • The research involved 45 OCD patients and 42 healthy controls, focusing on abnormalities in local degree centrality (DC) and dynamic functional connectivity (dFC) using resting-state fMRI.
  • Findings indicated reduced DC in brain regions like the thalamus and cuneus, correlated with illness severity, and decreased dFC variability, suggesting impaired connections in the visual and sensorimotor networks for those with OCD.
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Epipyrone A is a unique -galactosylated 4-hydroxy-2-pyrone derivative with an antifungal potential from the fungus . We elucidated its biosynthesis via heterologous expression and characterized an unprecedented membrane-bound pyrone -glycosyltransferase biochemically. Molecular docking and mutagenesis experiments suggested a possible mechanism for the heterocyclic -glycosylation and the importance of a transmembrane helix for its catalysis.

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Background: Langerhans cell histiocytosis (LCH) is a rare clonal proliferative disease of Langerhans cells with unknown pathogenesis. An increasing number of clinicians recognize that LCH has a wide clinical spectrum and a highly varied course. Adults rarely develop LCH.

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Ulcerative colitis (UC) is an inflammatory disease of the colon with an unmet need for therapeutic targets. Ethyl gallate (EG) is a natural small molecule for UC treatment, but its cellular target is unknown. By labelling EG with a diazirine photocrosslinker and a click chemistry handle, we identified phosphatidyl-ethanolamine binding protein1 (PEBP1) as a direct cellular target of EG by forming hydrogen bonds with Asp70 and Tyr120.

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Article Synopsis
  • - Neuroinflammation contributes to neuronal damage and is a significant focus for neurodegenerative disease treatment; understanding proteins like USP7 is crucial for developing therapies.
  • - The natural compound eupalinolide B (EB) targets USP7, inhibiting microglia activation by modifying a specific site on USP7, leading to degradation of Keap1 and activation of protective anti-neuroinflammatory genes in microglia.
  • - In studies with mouse models for dementia and Parkinson's disease, inhibiting USP7 with EB reduced microglia activation and neuron injury, improving behavioral outcomes, highlighting its potential as a therapy for neurodegenerative diseases.
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Ischemic stroke remains one of the leading causes of death worldwide, thereby highlighting the urgent necessary to identify new therapeutic targets. Deoxyhypusine hydroxylase (DOHH) is a fundamental enzyme catalyzing a unique posttranslational hypusination modification of eukaryotic translation initiation factor 5A (eIF5A) and is highly involved in the progression of several human diseases, including HIV-1 infection, cancer, malaria, and diabetes. However, the potential therapeutic role of pharmacological regulation of DOHH in ischemic stroke is still poorly understood.

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Engineering the function of triterpene glucosyltransferases (GTs) is challenging due to the large size of the sugar acceptors. In this work, we identified a multifunctional glycosyltransferase AmGT8 catalyzing triterpene 3-/6-/2'-O-glycosylation from the medicinal plant Astragalus membranaceus. To engineer its regiospecificity, a small mutant library was built based on semi-rational design.

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Background: We retrospectively reviewed and consecutively collected the clinical data of distal gastric cancer patients who received surgical treatment, and we discuss the safety and feasibility of double layered end-to-end anastomosis with continuous manual suture to complete digestive tract reconstruction in totally laparoscopic distal gastrectomy.

Methods: We reviewed the clinical data of 41 patients with distal gastric cancer from the gastroenterology department of the Second Affiliated Hospital of Dalian Medical University, from September 2018 to August 2019, who underwent totally laparoscopic distal gastrectomy. During the operation, the method of double layered end-to-end anastomosis with continuous manual suture was used for Billroth type I anastomosis to complete digestive tract reconstruction.

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Perfluorooctane sulfonate (PFOS), a classic environmental pollutant, is reported to cause cardiotoxicity in animals and humans. It has been demonstrated that PFOS exposure down-regulates expression of cardiac-development related genes and proteins. However, the related mechanism of PFOS has not been fully elucidated.

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A highly efficient di--glycosyltransferase GgCGT was discovered from the medicinal plant . GgCGT catalyzes a two-step di--glycosylation of flopropione-containing substrates with conversion rates of >98%. To elucidate the catalytic mechanisms of GgCGT, we solved its crystal structures in complex with UDP-Glc, UDP-Gal, UDP/phloretin, and UDP/nothofagin, respectively.

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Histone post-translational modifications (PTMs) are involved in various biological processes such as transcriptional activation, chromosome packaging, and DNA repair. Previous studies mainly focused on PTMs by directly targeting histone-modifying enzymes such as HDACs and HATs. In this study, we discovered a previously unexplored regulation mechanism for histone PTMs by targeting transcription regulation factor 14-3-3ζ.

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Licorice () is a popular medicinal plant containing more than 70 flavonoid and triterpenoid glycosides. Thus far, only a few reports are available on the glycosylation enzymes involved in their biosynthesis. In this work, we mined the transcriptome data of and discovered 43 candidate genes for -glycosyltransferase (-GT).

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Background: Angiostrongylus cantonensis is a human zoonotic nematode parasite. Our previous studies found that PAS-5 and Galectin-1 (Gal-1) proteins of A. cantonensis could be strongly recognized by sera from mice infected with A.

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Safflower yellow (SY), one of traditional Chinese medicine extracted from safflower, has been shown to have neuroprotective effects on animal models of vascular dementia and Alzheimer's diseases (AD), by inhibiting oxidative injury, neuronal apoptosis and tau hyperphosphorylation. In this study, we investigated whether safflower yellow (SY) can improve cognitive function, decrease Amyloid β (Aβ) accumulation and overactivation of astrocytes in AD mouse model. We found that SY treatment significantly ameliorated the learning and memory deficits of APP/PS1 mice.

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Objective: To clone and express the galectin-1 gene of Angiostrongylus cantonensis, and test the agglutination property of its protein.

Methods: The three-dimensional structure of galectin-1 was analyzed with Swiss Model. Total RNA was extracted from male worms of A.

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Alzheimer's disease (AD), the most common cause of dementia worldwide, is mainly characterized by the aggregated β-amyloid (Aβ) and hyperphosphorylated tau. Safflower yellow (SY) is a novel water extract of natural safflower and has been suggested to ameliorate memory deficits in several animal models of dementia. In this study, we aimed to investigate the effect and mechanism of SY on deficits of learning and memory and hyperphosphorylation of tau in APP/PS1 double transgenic mice.

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This paper is to investigate the optimization conditions of ultrasonic technique for extraction process of Xiaoqinglong granules in medium scale. First of all, single factor experiment was used to determine the overall impact tendency and range of each factor; secondly, Box-Behnken method was used for optimization and detecting the content of paeoniflorin, ephedrine hydrochloride, glycyrrhizic acid of the liquid medicine. Their respective extraction rate was calculated and the comprehensive evaluation was carried out.

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Insoluble plaques of amyloid β proteins (Aβ) and neurofibrillary tangles of hyperphosphorylated tau are key markers for Alzheimer's disease (AD). Safflower yellow (SY) is one of traditional Chinese medicine extracted from safflower, which is suggested to have therapeutic potential for neurodegenerative disorders. However, whether SY can ameliorate impairment of learning and memory in AD model, and its causal mechanism are still unclear.

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