Publications by authors named "Guowei Su"

Objectives: Understanding the different pharmacodynamic responses to narcotics in patients with or without obesity is particularly important for the safety of gastroscopy sedation. This study aimed to determine the median effective dose (ED50) of ciprofol combined with low-dose sufentanil to inhibit the response to gastroscope insertion in obese or nonobese patients.

Methods: A total of 27 obese patients (BMI 30-40 kg/m2) and 25 nonobese patients (BMI 18-25 kg/m2), aged between 18 and 65 years, with ASA physical status of 1-2, were included in this study.

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Article Synopsis
  • TREM2 is an important receptor in the immune system that plays roles in inflammation, cell survival, and neuroprotection, with variations linked to Alzheimer's disease.
  • The study investigates how TREM2 interacts with heparan sulfate (HS) on microglial cells, revealing that TREM2 forms complexes with HS and requires specific structural features of HS for effective binding.
  • Findings suggest that this interaction is crucial for TREM2's role in microglial function, particularly in facilitating the uptake of ApoE3, potentially offering targets for interventions in Alzheimer's disease.
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Heparan sulfate (HS), a sulfated polysaccharide abundant in the extracellular matrix, plays pivotal roles in various physiological and pathological processes by interacting with proteins. Investigating the binding selectivity of HS oligosaccharides to target proteins is essential, but the exhaustive inclusion of all possible oligosaccharides in microarray experiments is impractical. To address this challenge, we present a hybrid pipeline that integrates microarray and in silico techniques to design oligosaccharides with desired protein affinity.

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Cathepsin K (CtsK) is a cysteine protease with potent collagenase activity. CtsK is highly expressed by bone-resorbing osteoclasts and plays an essential role in resorption of bone matrix. Although CtsK is known to bind heparan sulfate (HS), the structural details of the interaction, and how HS regulates the biological functions of CtsK, remains largely unknown.

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Cathepsin K (CtsK) is a cysteine protease with potent collagenase activity. CtsK is highly expressed by bone-resorbing osteoclasts and plays an essential role in bone remodeling. Although CtsK is known to bind heparan sulfate (HS), the structural details of the interaction, and how HS ultimately regulates the biological functions of CtsK, remains largely unknown.

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Despite the recent progress on the solution-phase enzymatic synthesis of heparan sulfate (HS) and chondroitin sulfate (CS), solid-phase enzymatic synthesis has not been fully investigated. Here, we describe the solid-phase enzymatic synthesis of HS and CS backbone oligosaccharides using specialized linkers. We demonstrate the use of immobilized HS linker to synthesize CS, and the use of immobilized CS linker to synthesize HS.

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Fibrolamellar carcinomas (FLCs), lethal tumors occurring in children to young adults, have genetic signatures implicating derivation from biliary tree stem cell (BTSC) subpopulations, co-hepato/pancreatic stem cells, involved in hepatic and pancreatic regeneration. FLCs and BTSCs express pluripotency genes, endodermal transcription factors, and stem cell surface, cytoplasmic and proliferation biomarkers. The FLC-PDX model, FLC-TD-2010, is driven ex vivo to express pancreatic acinar traits, hypothesized responsible for this model's propensity for enzymatic degradation of cultures.

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Glycosaminoglycans (GAGs) are abundant, ubiquitous carbohydrates in biology, yet their structural complexity has limited an understanding of their biological roles and structure-function relationships. Synthetic access to large collections of well defined, structurally diverse GAG oligosaccharides would provide critical insights into this important class of biomolecules and represent a major advance in glycoscience. Here we report a new platform for synthesizing large heparan sulfate (HS) oligosaccharide libraries displaying comprehensive arrays of sulfation patterns.

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Article Synopsis
  • A specific genetic risk gene linked to Alzheimer's disease (AD) is overexpressed in patients, but its role in the disease progression remains unclear.
  • Researchers used a LC-MS/MS method to analyze brain heparan sulfate (HS) and found a sevenfold increase of a specific 3-sulfated HS in AD patients compared to other tauopathies.
  • The study suggests that the overexpression of the genetic risk gene may facilitate tau pathology spread by affecting tau cellular uptake, pointing to a new potential therapeutic target for Alzheimer's disease.
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Sulf-2 is an extracellular heparan 6-O-endosulfatase involved in the postsynthetic editing of heparan sulfate (HS), which regulates many important biological processes. The activity of the Sulf-2 and its substrate specificity remain insufficiently characterized in spite of more than two decades of studies of this enzyme. This is due, in part, to the difficulties in the production and isolation of this highly modified protein and due to the lack of well-characterized synthetic substrates for the probing of its catalytic activity.

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Apolipoprotein E (ApoE)'s ϵ4 alle is the most important genetic risk factor for late onset Alzheimer's Disease (AD). Cell-surface heparan sulfate (HS) is a cofactor for ApoE/LRP1 interaction and the prion-like spread of tau pathology between cells. 3-O-sulfo (3-O-S) modification of HS has been linked to AD through its interaction with tau, and enhanced levels of 3-O-sulfated HS and 3-O-sulfotransferases in the AD brain.

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Article Synopsis
  • Research on Alzheimer's disease shows a strong link between the decline in function and the spread of tau protein aggregates, with heparan sulfate proteoglycans (HSPGs) thought to facilitate this process.
  • The study specifically investigates the role of 3-O sulfation in heparan sulfate, finding that its absence or competition reduces the uptake of tau aggregates by cells.
  • The findings suggest that enhancing the interaction between tau aggregates and 3-O sulfated HS may offer a potential strategy for addressing tau-related pathology in Alzheimer's.
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Literature has well-established the importance of 3--sulfation of neuronal cell surface glycan heparan sulfate (HS) to its interaction with herpes simplex virus type 1 glycoprotein D (gD). Previous investigations of gD to its viral receptors HVEM and nectin-1 also highlighted the conformational dynamics of gD's N- and C-termini, necessary for viral membrane fusion. However, little is known on the structural interactions of gD with HS.

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Heparan sulfate (HS) regulates a wide range of biological events, including blood coagulation, cancer development, cell differentiation, and viral infections. It is generally recognized that structures of HS can critically impact its biological functions. However, with complex structures of naturally existing HS, systematic investigations into the structure-activity relationship (SAR) of HS and efforts to unlock their "sulfation code" have been largely limited due to the challenges in preparing diverse HS oligosaccharide sequences.

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Heparan sulfate (HS) has multifaceted biological activities. To date, no libraries of HS oligosaccharides bearing systematically varied sulfation structures are available owing to the challenges in synthesizing a large number of HS oligosaccharides. To overcome the obstacles and expedite the synthesis, a divergent approach was designed, where 64 HS tetrasaccharides covering all possible structures of 2-O-, 6-O- and N-sulfation with the glucosamine-glucuronic acid-glucosamine-iduronic acid backbone were successfully produced from a single strategically protected tetrasaccharide intermediate.

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Heparan sulfate (HS) and chondroitin sulfate (CS) are two structurally distinct natural polysaccharides. Here, we report the synthesis of a library of seven structurally homogeneous HS and CS chimeric dodecasaccharides (12-mers). The synthesis was accomplished using six HS biosynthetic enzymes and four CS biosynthetic enzymes.

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Heparan sulfates (HSs) are widely expressed glycans in the animal kingdom. HS plays a role in regulating cell differentiation/proliferation, embryonic development, blood coagulation, inflammatory response, and viral infection. The amount of HS and its structural information are critically important for investigating the functions of HS in vivo.

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Heparan sulfate (HS) 3--sulfotransferase isoform 4 (3-OST-4) is a specialized carbohydrate sulfotransferase participating in the biosynthesis of heparan sulfate. Here, we report the expression and purification of the recombinant 3-OST-4 enzyme and use it for the synthesis of a library of 3--sulfated hexasaccharides and 3--sulfated octasaccharides. The unique structural feature of the library is that each oligosaccharide contains a disaccharide domain with a 2--sulfated glucuronic acid (GlcA2S) and 3--sulfated glucosamine (GlcNS3S).

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Despite the potential of anti-thrombogenic coatings, including heparinized surfaces, to improve the performance of blood-contacting devices, the inevitable deterioration of bioactivity remains an important factor in device failure and related thrombotic complications. As a consequence, the ability to restore the bioactivity of a surface coating after implantation of a blood-contacting device provides a potentially important strategy to enhance its clinical performance. Here, we report the regeneration of a multicomponent anti-thrombogenic coating through use of an evolved sortase A to mediate reversible transpeptidation.

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Cystatin C (Cst-3) is a potent inhibitor of cysteine proteases with diverse biological functions. As a secreted protein, the potential interaction between Cst-3 and extracellular matrix components has not been well studied. Here we investigated the interaction between Cst-3 and heparan sulfate (HS), a major component of extracellular matrix.

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Heparan sulfate (HS) and heparin are sulfated polysaccharides exhibiting diverse physiological functions. HS 6-O-sulfotransferase (6-OST) is a HS biosynthetic enzyme that transfers a sulfo group to the 6-OH position of glucosamine to synthesize HS with desired biological activities. Chemoenzymatic synthesis is a widely adopted method to obtain HS oligosaccharides to support biological studies.

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Heparan sulfate is a sulfated polysaccharide that displays essential physiological functions. Here, we report a LC-MS/MS-based method for quantitatively determining the individual disaccharide composition and total amount of heparan sulfate. Using eight C-labeled disaccharide calibrants and one C-labeled polysaccharide calibrant, we complete the analysis in one-pot process.

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Chondroitin sulfate E (CS-E) is a sulfated polysaccharide that contains repeating disaccharides of 4,6-disulfated -acetylgalactosamine and glucuronic acid residues. Here, we report the enzymatic synthesis of three homogeneous CS-E oligosaccharides, including CS-E heptasaccharide (), CS-E tridecasaccharide (), and CS-E nonadecasaccharide (). The anti-inflammatory effect of was investigated in this study.

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