Publications by authors named "Zhenyan Shi"

An infrared laser (808 nm) has been coupled with dielectric barrier discharge (DBD) for optical emission spectrometric determination of S and Cl in organic compounds. The use of a continuous wave IR laser with an output power of 1-2 W allows volatilization of analytes from condensed surfaces. Analytes thermally delivered to the gas phase are excited and atomized by the DBD plasma triggered by an alternating voltage of 10 kV at 25 kHz under atmospheric pressure.

View Article and Find Full Text PDF

Lasers have long been used in the field of mass spectrometric analysis for characterization of condensed matter. However, emission of neutrals upon laser irradiation surpasses the number of ions. Typically, only one in about one million analytes ejected by laser desorption/ablation is ionized, which has fueled the quest for postionization methods enabling ionization of desorbed neutrals to enhance mass spectrometric detection schemes.

View Article and Find Full Text PDF

Accumulation of α‑synuclein (α‑SYN) is a common pathology for Parkinson's disease (PD). There is abundant evidence that the toxic‑gain‑of‑function of α‑SYN's is associated with aggregation and consequent effects. To assess the potential of chondroitin sulfate (CS) in this regard, the present study investigated its neuroprotective on SH‑SY5Y cells overexpressing wild‑type (WT) or A53T mutant α‑SYN.

View Article and Find Full Text PDF

TMG-promoted [3 + 2] organocatalytic 1,3-dipolar cycloaddition reactions of allyl ketones with in situ generated nitrile oxides have been developed. This strategy could generate 3,5-disubstituted isoxazolines in high yields and regioselectivities.

View Article and Find Full Text PDF

TMG-catalyzed [3 + 2] organocatalytic 1,3-dipolar cycloaddition reactions of β-functionalized ketones with nitrile oxides have been developed. This strategy could generate 3,4,5-trisubstituted isoxazoles in high yields and regioselectivities.

View Article and Find Full Text PDF

Sorafenib is the only and standard systematic chemotherapy drug for treatment of advanced hepatocellular carcinoma (HCC) at the current stage. Although sorafenib showed survival benefits in large randomized phase III studies, its clinical benefits remain modest and most often consist of temporary tumor stabilization, indicating that more effective first-line treatment regimens or second-line salvage therapies are required. The molecular pathogenesis of HCC is very complex, involving hyperactivated signal transduction pathways such as RAS/RAF/MEK/ERK and PI3K/AKT/mTOR and aberrant expression of molecules such as receptor tyrosine kinases and histone deacetylases.

View Article and Find Full Text PDF

Background: Ghrelin is an endogenous ligand for the growth hormone secretagogue receptor (GHS-R) and a peptide hormone that promotes food intake and gastric motility. Our aims are to explore the effects of ghrelin on gastric distension (GD) sensitive neurons in the lateral septum, and the possible regulation of gastric motility by ghrelin through the hypothalamic arcuate nucleus (ARC).

Methods: Single-unit discharges were recorded, extracellularly, and the gastric motility was monitored by the administration of ghrelin in the lateral septum.

View Article and Find Full Text PDF