Yun-Seok Yang

N-glycoproteomic analysis of human follicular fluid during natural and stimulated cycles in patients undergoing in vitro fertilization

Objective Hyperstimulation methods are broadly used for in vitro fertilization (IVF) in patients with infertility; however, the side effects associated with these therapies, such as ovarian hyperstimulation syndrome (OHSS), have not been well studied. N-glycoproteomes are subproteomes used for the remote sensing of ovarian stimulation in follicular growth. Glycoproteomic variation in human follicular fluid (hFF) has not been evaluated. In this study, we aimed to identify and quantify the glycoproteomes and N-glycoproteins (N-GPs) in natural and stimulated hFF using label-free nano-liquid chromatography/electrospray ionization-quad time-of-flight mass spectrometry. Methods For profiling of the total proteome and glycoproteome, pooled protein samples from natural and stimulated hFF samples were selectively isolated using hydrazide chemistry to obtain the total proteomes and glycoproteomes. N-GPs were validated by the consensus sequence N-X-S/T (92.2% specificity for the N-glycomotif at p<0.05). All data were compared between natural versus hyperstimulated hFF samples. Results We detected 41 and 44 N-GPs in the natural and stimulated hFF samples, respectively. Importantly, we identified 11 N-GPs with greater than two-fold upregulation in stimulated hFF samples compared to natural hFF samples. We also validated the novel N-GPs thyroxine-binding globulin, vitamin D-binding protein, and complement proteins C3 and C9. Conclusion We identified and classified N-GPs in hFF to improve our understanding of follicular physiology in patients requiring assisted reproduction. Our results provided important insights into the prevention of hyperstimulation side effects, such as OHSS.

Hybrid laparoscopic myomectomy: A novel technique

The objective of this study was to report on a new surgical technique, hybrid laparoscopic myomectomy that integrates the advantages of transumbilical laparoendoscopic single-site surgery and those of isobaric laparoscopy, and the initial experience with 14 cases. All of the procedures were performed by a single surgeon who has over 18 years of experience in laparoscopic surgery and 4 years of experience in laparoendoscopic single-site surgery. All cases of hybrid laparoscopic myomectomy were completed safely and effectively without conversion to conventional laparoscopic procedure. The median operative time was 75 minutes (range, 30 to 100 minutes). No postoperative complication was observed. The findings show that hybrid laparoscopic myomectomy is a safe and feasible surgical technique, and therefore can be a feasible, minimally invasive alternative to either abdominal or laparoendoscopic single-site surgery myomectomy.