Ji Eun Han

Recombinant human phospholipase C zeta 1 induces intracellular calcium oscillations and oocyte activation in mouse and human oocytes

BACKGROUND Oocyte activation is a crucial step that comprises the release of the oocyte from meiotic arrest, pronuclear formation and subsequent embryo development. Oocytes are activated by repetitive increases in the intracellular concentration of free Ca(2+), [Ca(2+)](i) oscillations, which are triggered during fertilization by the introduction of the sperm-specific phospholipase C zeta 1 (PLCZ1). Recent studies have shown that sperm from patients lacking expression of PLCZ1 or expressing mutant forms of PLCZ1 fail to induce [Ca(2+)](i) oscillations or oocyte activation. We first purified recombinant human PLCZ1 (hPLCZ1) protein and evaluated its [Ca(2+)](i) oscillation activity in mouse and human oocytes with the view to investigate its application in the clinic for assisted oocytes activation in lieu of chemical agents. METHODS Recombinant hPLCZ1 was synthesized using the Escherichia coli system, and subjected to immunoblot analysis with anti-PLCZ1 and anti-His tag antibodies. [Ca(2+)](i) oscillations by microinjection of recombinant hPLCZ1 into mouse or human oocytes were examined by [Ca(2+)](i) monitoring with Fluo 4. Ploidy of the oocytes with recombinant hPLCZ1 injection was confirmed with fluorescence in situ hybridization. RESULTS A band of 68 kDa on recombinant protein was detected with both antibodies. Injection of recombinant hPLCZ1 induced [Ca(2+)](i) oscillations in a dose-dependent manner in both mouse and human oocytes. These oscillations, which closely resembled those initiated by the sperm upon fertilization, triggered activation and cleavage in oocytes of both species, although further development of the mice embryos was low. U73122, a PLC inhibitor, blocked the ability of hPLCZ1 to initiate oscillations. Microinjection of recombinant hPLCZ1 into ICSI-failed human oocytes rescued fertilization failure in five of eight attempts. CONCLUSIONS Repeated [Ca(2+)](i) oscillations and oocyte activation were induced in mouse and human oocytes by microinjection of recombinant hPLCZ1 synthesized in E. Coli. Injection of recombinant protein could thus provide a biological solution for inducing artificial activation of oocytes.

Use of the natural cycle and vitrification thawed blastocyst transfer results in better in-vitro fertilization outcomes: Cycle regimens of vitrification thawed blastocyst transfer

PurposeTo compare the IVF outcomes of vitrification-thawed blastocyst transfer cycles utilizing different endometrial preparation methods.MethodsWe retrospectively assessed IVF outcomes in 611 patients (648 cycles) who underwent blastocyst frozen embryo transfer (FET) between January 2007 and December 2009. All embryos had been cryopreserved by a vitrification method following a previous IVF cycle. Patients were prepared for transfer by using either the natural cycle (n = 310/Group 1), the natural cycle with ovulation induction employing human chorionic gonadotropin (n = 134/Group 2), or a hormonally manipulated artificial cycle with estrogen and progesterone supplementation (n = 204/Group 3).ResultsMultivariate logistic regression analysis showed a significant difference in clinical pregnancy rate between Groups 3 (30.4%) and 1 (41.9%) (odds ratio [OR], 0.567; 95% confidence interval [CI], 0.379–0.847, P = 0.006) whereas the difference between Groups 2 and 1 was not significant (41.8% vs. 41.9%; OR, 0.683; 95% CI, 0.435–1.073; P = 0.098). Other significant variables affecting clinical pregnancy rate were the number of embryos transferred, the grade of transferred embryos, and maximal endometrial thickness.ConclusionThe results showed that, using vitrification-thawed blastocyst transfer, employment of natural cycles with or without hCG treatment was associated with better outcomes than was the use of hormonally manipulated cycles.

Relationship between endometrial and subendometrial blood flow measured by three-dimensional power Doppler ultrasound and pregnancy after intrauterine insemination.

OBJECTIVE To evaluate whether endometrial and subendometrial blood flow parameters measured using three-dimensional power Doppler ultrasound (3D PD-US) can predict pregnancy after IUI. DESIGN Prospective clinical study. SETTING Infertility center in a referral hospital. PATIENT(S) One hundred six women who underwent ovulation induction and IUI. INTERVENTION(S) A color Doppler ultrasound and a 3D PD-US examination were performed on the day of IUI. MAIN OUTCOME MEASURE(S) Pulsatility index (PI), resistance index (RI), and systolic/diastolic (S/D) ratio of uterine artery, and vascularization index (VI), flow index (FI), and vascularization flow index (VFI) of the endometrium as well as those of subendometrial region. These measurements were analyzed in relation to IUI outcome (pregnant vs. nonpregnant). RESULT(S) The pregnant group had higher endometrium VI, FI, and VFI scores than the nonpregnant group. In contrast, the subendometrial region VI, FI, and VFI scores did not differ between the groups, nor did the uterine artery PI, RI, and S/D. Pregnancies did not occur when endometrial blood flow had not been detected. CONCLUSION(S) Three-dimensional PD-US was useful for evaluating endometrial and subendometrial neovascularization in IUI cycles. Endometrial blood flow parameters may be useful predictors for pregnancy.

Preimplantation genetic diagnosis for couples with a Robertsonian translocation: practical information for genetic counseling

SummaryPurposeTo evaluate the proportions of abnormal and normal embryos detected by preimplantation genetic diagnosis (PGD) of infertile couples of whom one was a Robertsonian translocation (RT) carrier, and to provide practical information, including details of reproductive outcomes, to aid in genetic counseling of such couples.MethodsWe retrospectively analyzed all PGD cycles conducted to deal with RT at our center between January 2000 and December 2009. Subject demographic and clinical data were compared with the results of PGD.ResultsEmploying PGD, we conducted a total of 66 cycles on 34 couples of whom one was an RT carrier, including 24 female and 10 male carriers. Of the 514 blastomeres tested, 161 (31.3%) were normal or balanced. Of the 57 cycles that included embryo transfer, 17 (29.8%) attained positivity for human chorionic gonadotropin (hCG). A total of 17 embryos were implanted and 16 babies, including two sets of twins, were born. The takehome baby rate was 41.2% per couple and the loss rate 6.6%. Receiver operating characteristic curve analysis showed that the proportion of alternate embryos associated with a sensitivity of 70.6% for prediction of clinical pregnancy following PGD was 0.31. Sex of the carrier and type of translocation were not significantly associated with pregnancy outcomes.ConclusionCouples with RT may benefit from PGD; pregnancy success rate is improved and embryo loss reduced. We found that about 30% of embryos were of normal or balanced chromosomal constitution and that the percentage of normal or balanced embryos was predictive of PGD outcome.

High sensitivity C-reactive protein and its relationship with impaired glucose regulation in lean patients with polycystic ovary syndrome

The polycystic ovary syndrome (PCOS) is the most common endocrine-metabolic disorder, also associated with the metabolic syndrome. Serum high sensitivity C-reactive protein (hs-CRP), a marker of low-grade chronic inflammation is a potent predictor of cardiovascular events, closely linked to metabolic syndrome features and higher in patients with PCOS. However, hs-CRP in lean patients with PCOS has not been fully evaluated and few data are available. We aimed to investigate the relation between glucose intolerance and hs-CRP levels in lean patients with PCOS, and to evaluate the possible relationship between hs-CRP and PCOS by evaluating PCOS-related metabolic abnormalities in Korean women. We consecutively recruited 115 lean (BMI < 25kg/m2) patients diagnosed with PCOS and 103 lean healthy controls. The PCOS group was divided two groups: impaired glucose regulation (IGR) and normal glucose tolerance group (NGT). In lean patients with PCOS, hs-CRP level was higher in the IGR group than in the NGT group (0.60 ± 1.37 versus 0.18 ± 0.46, pBonf = 0.023) and other metabolic risk factors were also higher in the IGR group than in the NGT group. And there were close relationships between hs-CRP level and metabolic risk factor, such as 2 h postprandial insulin level in the lean patients with PCOS.

Term delivery following tuboovarian abscess after in vitro fertilization and embryo transfer

A tuboovarian abscess (TOA) during pregnancy following oocyte retrieval is extremely rare. We report a rare case of pregnancy complicated by the development of a TOA following in vitro fertilization-embryo transfer that was treated successfully with laparoscopy. We also review all similar cases reported in the English-language literature.