41 research outputs found
Improved development of mouse and human embryos using a tilting embryo culture system
Mammalian embryos experience not only hormonal but also mechanical stimuli, such as shear stress, compression and friction force in the Fallopian tube before nidation. In order to apply mechanical stimuli to embryos in a conventional IVF culture system, the tilting embryo culture system (TECS) was developed. The observed embryo images from the TECS suggest that the velocities and shear stresses of TECS embryos are similar to those experienced in the oviduct. Use of TECS enhanced the development rate to the blastocyst stage and significantly increased the cell number of mouse blastocysts (P < 0.05). Although not statistically significant, human thawed embryos showed slight improvement in development to the blastocyst stage following culture in TECS compared with static controls. Rates of blastocyst formation following culture in TECS were significantly improved in low-quality embryos and those embryos cultured under suboptimal conditions (P < 0.05). The TECS is proposed as a promising approach to improve embryo development and blastocyst formation by exposing embryos to mechanical stimuli similar to those in the Fallopian tube
Uterine Epithelial Cell Regulation of DC-SIGN Expression Inhibits Transmitted/Founder HIV-1 Trans Infection by Immature Dendritic Cells
Sexual transmission accounts for the majority of HIV-1 infections. In over 75% of cases, infection is initiated by a single variant (transmitted/founder virus). However, the determinants of virus selection during transmission are unknown. Host cell-cell interactions in the mucosa may be critical in regulating susceptibility to infection. We hypothesized in this study that specific immune modulators secreted by uterine epithelial cells modulate susceptibility of dendritic cells (DC) to infection with HIV-1.Here we report that uterine epithelial cell secretions (i.e. conditioned medium, CM) decreased DC-SIGN expression on immature dendritic cells via a transforming growth factor beta (TGF-β) mechanism. Further, CM inhibited dendritic cell-mediated trans infection of HIV-1 expressing envelope proteins of prototypic reference. Similarly, CM inhibited trans infection of HIV-1 constructs expressing envelopes of transmitted/founder viruses, variants that are selected during sexual transmission. In contrast, whereas recombinant TGF- β1 inhibited trans infection of prototypic reference HIV-1 by dendritic cells, TGF-β1 had a minimal effect on trans infection of transmitted/founder variants irrespective of the reporter system used to measure trans infection.Our results provide the first direct evidence for uterine epithelial cell regulation of dendritic cell transmission of infection with reference and transmitted/founder HIV-1 variants. These findings have immediate implications for designing strategies to prevent sexual transmission of HIV-1
Assessment of follicle viability using fluorescence microscopy before & after ovarian thawing
The incidcncc of young women diagnosed with cancer has been globally increasing. In many cases the surgical approach followed by chemotherapy, radiotherapy or hormonal therapy could lead to infertility or premature ovarian failure. Several options are available in order to preserve fertility and increase the future gestation rate. Among embryo cryopreservation and oocyte cryopreservation, ovarian tissue cryopreservation represents an ideal option, especially for premenopausal women and for those who cannot delay the start of chemotherapy. The purpose of this study was to examine the follicle viability using fluorescence microscope before and after ovarian thawing
Single nucleotide polymorphisms in the Anti-Mullerian hormone (AMH Ile(49)Ser) and Anti-Mullerian hormone type II receptor (AMHRII-482 A > G) as genetic markers in assisted reproduction technology
The aim of the study was to evaluate whether the presence Antimullerian
hormone (AMH) and Antimullerian hormone type II receptor (AMHRII) single
nucleotide polymorphisms (SNPs) Ile(49)Ser and -482A > G respectively
are related to the assisted reproduction outcome.
A prospective cross-sectional observational study was conducted in order
to assess the distribution of AMH and AMHRII SNPs in two cohorts, one of
healthy women (N = 100) and the control group and the IVF/ICSI group (N
= 151) consisted of women undergoing IVF/ICSI treatment for infertility.
Furthermore, a prospective longitudinal observational study was
performed on the latter group to assess possible associations of these
SNPs with patients’ characteristics and controlled ovarian stimulation
(COS) and pregnancy outcome.
Among non-carriers of the AMH (Ile(49)Ser) polymorphism, basal FSH
levels were lower in those with more than two of previous IVF attempts
and fertilization rate was statistically higher in those with peak serum
E2 levels below 1500 pg/ml, whereas among non-carriers of the AMHRII
(-482 A > G) polymorphism, number of follicles was higher in those with
more than two previous IVF attempts and total dose of gonadotropins was
lower in those with peak serum E2 levels above 1500 pg/ml.
There was evidence that in specific subgroups of women undergoing
IVF/ICSI, AMH and AMHRII SNPs may be related to patients’
characteristics and controlled ovarian stimulation and pregnancy outcome
and thus may provide a means for the prediction of ovarian response in
specific subgroups of women entering an IVF/ICSI program
Cleavage stage versus blastocyst stage embryo transfer in oocyte donation cycles
Background and Objective: During the last few years, a trend has been noted towards embryos being transferred at the blastocyst stage, which has been associated with improved rates regarding implantation and clinical pregnancy in comparison to cleavage stage embryo transfers. There is a limited number of studies investigating this notion in oocyte donation cycles employing cryopreserved embryos. The aim of this study is to evaluate the implantation potential and clinical pregnancy rates between the day 3 cleavage stage and blastocyst stage embryo transfers in oocyte donation cycles employing vitrified embryos. Methods: This is a retrospective evaluation of oocyte donation frozen–thawed transfers completed in our clinic from January 2017 to December 2017. Intracytoplasmic sperm injection was conducted for all oocytes. Following fertilization, all embryos were cryopreserved either at the cleavage or blastocyst stage. Embryo transfer of two embryos was performed under direct sonographic guidance in all cases. Results: Our results confirmed a 55.6% clinical pregnancy (CP) resulting from day 3 embryo transfers, a 68.8% CP from day 5, and 71.4% CP from day 6. Significantly improved pregnancy rates were related to embryo transfers at the blastocyst stage when compared to cleavage stage transfers (68.9% and 55.6% respectively, p = 0.016). The risk with regards to multiple pregnancies was similar. Conclusion: Our findings indicate that in oocyte donation cycles employing vitrified embryos, embryo transfer at the blastocyst stage is accompanied with a significant improvement in pregnancy rates and merits further investigation. © 2019 by the authors. Licensee MDPI, Basel, Switzerland