EFFECT OF NAC ON MOUSE GV OOCYTE SURVIVAL AND SUBSEQUENT EMBRYONIC DEVELOPMENT FOLLOWING VITRFICATION.

BACKGROUND: Oocytes that survive cryopreservation may accumulate ROS which are known to bring harmful effects on embryonic development. NAC is an antioxidant which can be a supplement to reduce oxidative stress. However, whether NAC can improve the developmental competence of vitrified GV-oocytes remains unclear. OBJECTIVE: The study was to investigate the effect of NAC on subsequent embryonic developmental competence of mice vitrified GV-oocytes. MATERIALS AND METHODS: This study compared the effects of different concentration of NAC on the cleavage and blastocyst rates of mice vitrified GV-oocytes. Then the effects of NAC on mitochondria distribution, ROS level and embryonic development of vitrified oocytes were tested. RESULTS: ROS activity of vitrified oocytes was significantly annihilated and mitochondrial distribution pattern was improved by 1.5 mM NAC (P<0.05). NAC supplementation throughout vitrification/warming and IVM media significantly improved the developmental competence of vitrified oocytes. CONCLUSION: Supplementation of NAC could partially overcome the damages by vitrification and improve the development ability of mice vitrified GV-oocytes.

[Preoperative prognostic factors and preoperative risk stratification of upper tract urothelial carcinoma].

OBJECTIVE: To identify the preoperative prognostic factors of upper tract urothelial carcinoma (UTUC) and construct preoperative risk stratification system. METHODS: A retrospective study including 686 patients who were diagnosed with UTUC and received radical nephroureterectomy or partial ureterectomy in Peking University First Hospital during 2003 and 2013. RESULTS: Of the 686 UTUC patients, 303 (44.2%) were male and 383 (55.8%) female. The postoperative pathological examination showed that 203 (29.6%) had high tumor stages (T3, T4), 300 (43.7%) had high tumor grades (G3) and 54 (7.9%) had lymph nodes metastasis (N1). After multivariate analysis, renal pelvic tumor, large tumor, estimated glomerular filtration rate (eGFR)≥30 mL/min, and male were associated with high tumor stage. Ureteral tumor, large tumor, and non-smoking history were associated with high tumor grade. Renal pelvis tumor, large tumor, and preoperative anemia were associated with positive N status. During the follow-up, 208 (30.3%) died for cancer and 210 (30.6%) developed intravesical recurrence. Multivariate analysis showed: large tumor (P=0.001), concomitant ipsilateral hydronephrosis (P=0.041), and preoperative anemia (P=0.001) were independently associated cancer-specific mortality after surgery, while ureteral tumor (P=0.04), multiple tumor (P=0.005), and high preoperative creatinine (P=0.036) were independent risk factors for intravesical recurrence. CONCLUSION: Of the preoperative clinical parameters of UTUC patients, the large tumor, concomitant ipsilateral hydronephrosis, and preoperative anemia were independently associated with cancer-specific mortality after surgery. Ureteral tumor, multiple tumor, and high preoperative creatinine were independently associated with intravesical recurrence after surgery.