Publications by authors named "Xikai Cui"

A facile and green -glycosylation method has been developed featuring protecting-group-free and proceeding-in-water like enzymatic synthesis. Glycosylation of fluoride donors with thiol sugar acceptors using Ca(OH) as a promoter afforded various thioglycosides in good yields with exclusive stereoselectivity. This method also enabled the successful production of -linked oligosaccharides and -linked glycopeptides.

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Noroviruses are known to bind to histo-blood group antigens (HBGAs) and the specific binding patterns depend on the virus genotype. However, the development of point-of-care diagnostic assays based on this binding has been challenging due to low assay sensitivity. This study utilized a well-defined stool collection from a GII.

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Early and accurate diagnosis of influenza viruses can decrease its harmful impact. Here, we have synthesized fluorescent sialic acid derivatives that are cleaved by influenza neuraminidases (NAs) and not by Streptococcus pneumoniae that also inhabits the human olfactory. We have also attempted to develop assays that could differentiate between influenza virus and S.

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We have developed innovative assays that can detect enzymes rapidly. Paracetamol- or catechol-bearing compounds, when exposed to their respective enzymes, released paracetamol or catechol, which can be detected using a standard glucose meter. This approach was used to detect a number of diverse analytes that include enzymes such as β-galactosidase and α-mannosidase and pathogens such as influenza viruses, Streptococcus pneumoniae, and E.

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Rapid and precise detection of influenza viruses in a point of care setting is critical for applying appropriate countermeasures. Current methods such as nucleic acid or antibody based techniques are expensive or suffer from low sensitivity, respectively. We have developed an assay that uses glucose test strips and a handheld potentiostat to detect the influenza virus with high specificity.

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A large number of proteins in malaria parasites are anchored using glycophosphatidylinositols (GPIs) with lipid tails. These GPIs are structurally distinct from human GPIs. Plasmodium falciparum GPIs have been considered as potential vaccine candidates because these molecules are involved in inducing inflammatory responses in human hosts, and natural anti-GPI antibody responses have been shown to be associated with protection against severe disease.

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Glycosidases are essential enzymes that cleave glycoside bonds. The presence of glycosidases have been widely used to detect pathogens, label cells/tissues, and report specific diseases. We have developed a rapid electrochemical assay to detect glycosidases.

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QDs with different fluorescence emission wavelengths were coated with galactose, glucose, and lactose respectively. The formulas of glyco-QDs were determined by NMR and ICP-OES, and the interactions between glyco-QDs and PNA lectin were investigated by SPR. The results showed that multivalent presentation achieved by using QDs as the scaffold is an effective way to enhance the carbohydrate-protein interactions.

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2-Deoxyglycosides were synthesized in high α-selectivity by the direct addition of alcohols to D-glucal and D-galactal catalyzed by TMSI and PPh(3). The acid labile isopropylidene group is tolerated under this condition.

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