A case of placental site trophoblastic tumor complicating nephrotic syndrome in which hysteroscopic biopsy did not yield a definitive diagnosis.

Placental site trophoblastic tumor (PSTT) is the rarest subtype of gestational trophoblastic neoplasm. We present a case of PSTT complicating nephrotic syndrome. A 32-year-old woman experienced irregular menstrual bleeding and lower extremity edema 18 months after delivery. She was diagnosed with nephrotic syndrome and exaggerated placental site based on the hysteroscopic biopsy results. During follow-up, transvaginal color Doppler ultrasound showed an enlarged uterus filled with a hypervascular mass. Positron emission tomography-computed tomography showed diffuse accumulation in the entire uterus. The patient was diagnosed with PSTT only after total hysterectomy. Postoperatively, serum ß-human chorionic gonadotropin decreased to within the normal range and her nephrotic syndrome resolved. She has remained without evidence of recurrence for 15 months. It is difficult to diagnose PSTT definitively. Most patients with PSTT are of reproductive age, therefore, to maintain fecundity, therapy development is expected.

Time-lapse monitoring reveals that vitrification increases the frequency of contraction during the pre-hatching stage in mouse embryos.

Contraction during the blastocyst stage is observed during embryonic development of various mammals, including humans, but the physiological role of this process is not well understood. Using time-lapse monitoring (TLM), we studied the influence of vitrification and contractions on embryonic development in mice. Mouse embryos were cultured at the 2-cell stage. At the 8-cell stage, embryos were randomly divided into a fresh group (FG) and vitrified group (VG) and observed for up to 144 h. Strong contractions (i.e., contractions causing a decrease in volume of more than 20% and expansion of the perivitelline space) occurred significantly more often in unhatched embryos than hatching embryos in both groups. Regarding hatching embryos, contractions in the pre-hatching stage were significantly more frequent in the VG than the FG. Furthermore, mRNA expression levels of genes related to contractions were determined at three time points, the 8-cell stage, early blastocyst stage, and 20 h after blastocoel formation, with quantitative reverse transcription-polymerase chain reaction. There was no significant difference in Hspa1a expression between the FG and VG, but Hspa1a overexpression was observed just after thawing and tended to decrease gradually thereafter in some blastocysts. Furthermore, in the VG, Atp1a1 tended to show higher expression in the strong contraction group than in the weak contraction group. Overall, vitrification is an excellent method for cryopreservation but could increase contractions in the pre-hatching stage and may increase energy demands of the embryo. Observation of contraction by TLM may improve the evaluation of embryo quality.