In pediatric posttransplantation patients, CMV viremia mostly occurred within 100 days after transplantation. Risk factors associated with CMV viremia include older diagnostic age, leukemic patients, unrelated donor HSCT, pretransplant ATG use, GvHD, and gastrointestinal GvHD.

A new chemical method for the traceless labeling of glycoproteins with synthetic boronic acid (BA)-tosyl probes was successfully developed. The BA moiety acts as an affinity head to direct the formation of a cyclic boronate diester with the diol groups of glycans. Following this step, the electrophilic tosyl group is displaced by an SN2 reaction with a nucleophilic residue of the boronated glycoprotein, and finally, a reporter group is tagged onto the glycoprotein via an ether linkage. In the presence of polyols, a competition reaction recovers the native glycan of the tagged glycoprotein, conserving its biological significance. The BA-tosyl probes were used successfully for the specific labeling of glycosylated fetuins in a mixed protein pool and from crude Escherichia coli (E. coli) lysate. Further, a BA-tosyl-functionalized glass slide was used to fabricate glycoprotein microarrays with highly conserved glycans. By interacting with various lectins (carbohydrate-binding proteins), such as Concanavalin A (Con A) and wheat germ agglutinin (WGA), the types of carbohydrates and specific linkages of glycoproteins (α or β) could be systematically monitored. It is believed that the newly developed method will greatly accelerate the understanding of glycoproteins.

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A nanomaterial-assisted method that combines thin layer chromatography (TLC) with matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) was developed to directly monitor chemical transformations. A substrate-dependent extraction strategy was studied and successfully used to identify target molecules from the depths of a developed TLC plate. By using this strategy, a hydrophobic sample of interest was enriched on the surface of the TLC plate in the presence of acetonitrile, in contrast to using water and methanol to identify hydrophilic samples. The successful enrichment of samples by specific solvents provided stable desorption/ionization efficiencies of compounds of interest and led to very good sensitivity near the attomole scale. The method was then used to monitor 4-dimethylaminopyridine (DMAP)-catalyzed acylation in preparation of bifunctional sulfonamides. The labile DMAP-acyl intermediate and final sulfonamide product were clearly identified on TLC plates without external purification or sample preparation. Furthermore, in combination with collision-induced dissociation (CID) to provide structural information, the technique was successfully used in the natural product discovery of anti-inflammatory flavonoids from Helminthostachys zeylanica, a traditional Chinese herb. The newly proposed method provides a very low background from silica supports or organic matrices in the low molecular weight range (100-1000 Da). The technique may greatly accelerate studies of metabolomics, drug discovery, and organic synthesis.

In this work we have studied the surface plasmon resonance (SPR) absorption of Albumin on NiSi nanoparticle thin film deposited on Si. The thin films were deposited by means of RF sputtering on Si at various temperatures and times for different thicknesses, and characterized by grazing angle XRD and SEM. From these experimental conditions, we only observed a formation of NiSi nanoparticles deposited on Si at 230°C for 15 min to 30 min. The silicon atoms seem to emerge out of the surface and react with Nickel's. Due to the high activation energy, this mechanism would not take place at lower temperatures, such as RT and 122°C. Mixture of Albumin and water with varied concentrations has been prepared for the measurement of SPR absorption on the NiSi nanoparticle thin film. We found the spectra of SPR absorption of Albumin on the sample, which NiSi nanoparticle thin film was deposited on Si at 230°C, exhibits a specific shift due to the formation of NiSi nanoparticle.