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Study Question: Are mRNAs for specific aquaporins (AQPs) expressed in human luteinized granulosa cells (GCs) and are their expression levels correlated with in vitro fertilization (IVF) outcomes?Summary Answer: The mRNAs of AQP1-7, 9, 11, and 12 were expressed in human luteinized GCs; the level of AQP1 mRNA was negatively associated with retrieved oocyte number and the level of AQP7 mRNA was positively associated with fertilization rate.What Is Known Already: mRNAs of AQP1-4 and AQP9 have been detected in human GCs.Study Design, Size, Duration: Prospective observational study involving 111 women undergoing a stimulated IVF cycle.Participants/materials, Setting, Methods: In a preliminary experiment on 27 women, the mRNA expression of AQP0-12 in GCs was explored by RT-PCR. In the main experiment, luteinized GCs were obtained from 111 women at the time of oocyte retrieval of whom 102 had an embryo replacement. Real-time quantitative RT-PCR (qRT-PCR) was performed to quantify the mRNA level of AQP1-7, 9, 11, and 12. The mRNA for luteinizing hormone receptor (LHR) and steroidogenic acute regulatory protein (StAR) were also quantified by qRT-PCR.Main Results and the Role Of Chance: mRNAs for AQP0, 8 and 10 were not detected in the preliminary experiment. In samples from 111 women, retrieved oocyte number was negatively associated with the mRNA levels of AQP1, 4, 6, and 11 and LHR (r = -0.311, r = -0.233, r = -0.203, r = -0.194, and r = -0.202, respectively, P < 0.05 for each), however, after adjustment for woman's age and serum anti-Müllerian hormone (AMH) levels, only correlation with AQP1 was found (r = -0.299, P < 0.05). BMI was negatively associated (after adjustment for age) with the mRNA level of AQP7 (r = -0.259, P < 0.05). Fertilization rate was positively associated with the mRNA level of AQP7 (r = 0.269, P < 0.05). The number or quality of embryos or clinical pregnancy was not associated with the mRNA levels of any of ten AQP subtypes. The mRNA levels for the ten AQP subtypes were correlated positively with LHR expression but negatively with StAR expression. Amongst high responders (oocyte number ≥14), the mRNA levels of AQP11 (1.4 ± 0.7 versus 1.7 ± 0.6) and LHR (1.3 ± 0.7 versus 1.7 ± 0.7) were significantly lower in the group with PCOS than in the non-PCOS group.Limitations, Reasons For Caution: A relative small number of subjects in PCOS group is the main limitation of our study. P-values were not corrected for multiple comparisons.Wider Implication Of the Findings: AQP1 may be one of the factors that modulate individual ovarian response to exogenous gonadotrophin. The mRNA level of AQP7 was positively associated with fertilization rate, which is a surrogate marker of oocyte competence, thus expression of AQP7 could be a marker for adequate folliculogenesis and healthy oocytes.Study Funding/competing Interests: This work was supported by grant no. A120043 from the Korea Health Care Technology R&D Project, Ministry of Health and Welfare, Korea. None of the authors has any conflict of interest to declare. [ABSTRACT FROM AUTHOR]

BACKGROUND: Anti-Müllerian hormone (AMH) has been suggested as a marker of ovarian reserve and predictor of ovarian response to controlled ovarian hyperstimulation (COH). Several studies have demonstrated AMH changes during follicular and luteal phases during COH, but not after human chorionic gonadotrophin (hCG) administration. The objectives of this study were to investigate changes in AMH levels during the entire COH cycle and to clarify the regulatory mechanism of AMH secretion. In addition, we analyzed the COH outcome parameters to determine the optimal timing for AMH measurement to predict outcome. [ABSTRACT FROM AUTHOR]

BACKGROUND: Age at menarche is known to be regulated by genetic and environmental factors. To date, no menarcheal data are available on North Korean women. In this cross-sectional survey, we investigated age at menarche and its possible influencing factors in North Korean refugees. METHODS: Four hundred and eleven North Korean refugees were surveyed at a North Korean female refugee camp using a structured questionnaire within 3 months of immigration. Menarcheal age was requested and the data obtained were analysed with respect to age at interview, region of residence in North Korea, education, food preference and sleep duration. RESULTS: Mean age at menarche was 16.0 ± 2.1 years (mean ± SD). Univariate analysis demonstrated a significant difference in the menarcheal age among the different food preference groups (P = 0.0236). Sleep duration was found to be significantly and negatively correlated with age at menarche (R = −0.23, P < 0.0001). However, generalized linear model (GLM) analysis revealed that region of residence at menarche (P = 0.0209) and sleep duration (P = 0.0007) were significant determinants. Food preference played a role as an effect modifier in the relationship between the region of residence at menarche and age at menarche. CONCLUSION: Age at menarche seemed to be delayed in North Korean refugees. GLM analysis showed that sleep duration and region of residence at menarche were significant influencing factors of age at menarche in this study population. [ABSTRACT FROM AUTHOR]

BACKGROUND: This study was carried out to compare spindle locations and their developmental competencies both in vivo and in vitro in matured mouse oocytes. Spindle locations were identified using a polscope. Since meiotic spindles in living oocytes are highly birefringent, their structures can be viewed non-invasively by using a polscope. METHODS: In vivo matured metaphase II oocytes were collected from the oviducts of mice. Immature oocytes were collected from mouse ovaries, and then cultured in YS medium until the first polar body (PB) extrusion. In vitro and in vivo matured oocytes were classified into four categories according to their spindle positions relative to the first PB (0, 090, 90180 and without a spindle image), and rates of fertilization and blastocyst formation were assessed. In vivo matured oocytes with a 0 spindle disposition relative to PB were cultured in vitro for 24?h, and then their spindle positions were re-assessed. RESULTS: Most in vivo matured oocytes (89.1%) had a 0 spindle position. Only 6 and 3% of oocytes had spindle positions of 090 and 90180, respectively. No spindle image was observed in 2%. However, most in vitro matured oocytes (83.1%) had a 090 spindle position and, in contrast, only 6.5% of these oocytes had a 0 spindle position. The rate of fertilization and blastocyst rate were significantly higher for in vivo matured oocytes than in vitro matured oocytes (87.1 versus 64.9% and 76.1% versus 66.0%, respectively, P<0.05 for each). We also observed that 71.7% of the in vivo matured oocytes with the 0 spindle position showed a spindle position change to 090 after 24?h of culture. These oocytes had a poor fertilization rate (43%) and a zero blastocyst rate. CONCLUSION: In vitro matured mouse oocytes showed quite different spindle positions compared with in vivo matured oocytes. Moreover, in vivo matured oocytes cultured for 24?h had a spindle position distribution that was similar to that of in vitro matured oocytes. The different spindle positions observed in in vivo and in vitro matured oocytes may reflect differences in their cytoplasmic maturation processes. These findings have implications regarding the lower developmental competency of in vitro matured oocytes. [ABSTRACT FROM AUTHOR]

BACKGROUND: An effective freezing–thawing technique is crucial for the clinical application of human embryonic stem (ES) cells. The aim of this study was to find an optimal cryopreservation protocol for human ES cells using slow freezing–rapid thawing without a programmable freezer. METHODS: The human ES cell line, SNUhES-3, was cultured on an STO feeder layer in gelatin-coated tissue culture dishes. All cryopreservation steps were performed using a simple commercial freezing container. The survival rate of cryopreserved–thawed human ES cells was estimated by counting colony numbers under a stereomicroscope. Initially, we compared the survival rates of cryopreserved human ES cells using three cryoprotectants: dimethylsulphoxide (DMSO), ethylene glycol (EG) and glycerol. In this experiment, 5% DMSO/95% fetal bovine serum (FBS) (vol/vol) showed the highest survival rate. We next tested the impact of various concentrations of FBS (95, 50 and 5%) with 5% DMSO, and then examined the effects of adding EG or glycerol to 5% DMSO + optimal FBS. RESULTS: No significant difference in survival rate was observed between 95 and 50% FBS in the presence of 5% DMSO. A significant improvement in survival rate was obtained by adding 10% EG to 5% DMSO+50% FBS. After thawing, surviving cells were found to maintain the inherent characteristics of human ES cells. CONCLUSION: 5% DMSO+50% FBS+10% EG may be an optimal cryoprotectant for the slow freezing–rapid thawing of human ES cells. [ABSTRACT FROM AUTHOR]

BACKGROUND Insulin resistance is a core feature of polycystic ovary syndrome (PCOS). Phosphatidylinositol (PI) 3-kinase is an important enzyme in the early insulin signaling cascade and plays a key role in insulin-mediated glucose transport. In its regulatory subunit, p85α, there is a common amino acid substitution (the Met326Ile polymorphism), and this amino acid may be crucial for the function of the p85α regulatory subunit and PI3-kinase. METHODS Analysis of the Met326Ile polymorphism was carried out on DNA samples from 256 PCOS patients and 283 controls. Clinical and biochemical profiles of participants were also compared. RESULTS The genotype distribution of the Met326Ile polymorphism in the PCOS group was not different from that of the controls (Met326Met/Met326Ile/Ile326Ile rates were 73.4%/23.4%/3.2% and 70.3%/26.1%/3.6% for the PCOS and control groups, respectively, P = 0.72). The PCOS group was divided into two subgroups according to the presence of the variant 326Ile allele. Compared with those carrying at least one variant 326Ile allele, carriers with the Met326Met genotype had higher serum 17-hydroxyprogesterone (17-OHP) {1.1 [95% confidence interval (CI) 1.1–1.3] ng/ml in those with the Met326Met genotype versus 0.8 (95% CI 0.7–1.0) ng/ml in those with Ile326Ile and Met326Ile genotypes, P = 0.0073} and free testosterone levels [1.2 (95% CI 1.1–1.4) pg/ml for Met326Met genotype versus 0.9 (95% CI 0.6–1.3) pg/ml for Ile326Ile and Met326Ile genotypes, P = 0.038]. CONCLUSIONS Our results suggest that the PI3-kinase gene Met326Ile polymorphism may not be a major determinant for the development of PCOS, but it may modulate the concentrations of serum 17-OHP or free testosterone in PCOS patients. [ABSTRACT FROM AUTHOR]

BACKGROUND A cryopreservation protocol for human amnion-derived mesenchymal stem cells (HAMs) is required because these cells cannot survive for long periods in culture. The aim of this study was to determine whether vitrification is a useful freezing method for storage of HAMs. METHODS HAMs were cryopreserved using vitrification method. The morphology and viability of thawed HAMs was evaluated by Trypan Blue staining. The expression of several embryonic stem cell (ESC) markers was evaluated using flow cytometry, RT–PCR and immunocytochemistry. Von Kossa, Oil Red O and Alcian Blue staining were used to asses the differentiation potential of thawed HAMs. RESULTS The post-thawing viability of HAMs was 84.3 ± 3.2% (Mean ± SD, n = 10). The thawed HAMs showed morphological characteristics indistinguishable from the non-vitrified fresh HAMs. The expression of surface antigens (strong positive for CD44, CD49d, CD59, CD90, CD105 and HLA-ABC; weak positive for HLA-G; negative for CD31, CD34, CD45, CD106, CD117 and HLA-DR) and the expression of ESC markers [CK18, fibroblast growth factor-5, GATA-4, neural cell adhesion molecule, Nestin, Oct-4, stem cell factor, HLA-ABC, Vimentin, bone morphogenetic protein (BMP) 4, hepatocyte nuclear factor 4α (HNF-4α), Pax-6, alpha-fetoprotein, Brachyury, BMP-2, TRA-1-60, stage-specific embryonic antigen (SSEA-3, SSEA-4)] were maintained in the vitrified-thawed HAMs. The thawed HAMs retained ability to differentiate into osteoblasts, adipocytes and chondrocytes under appropriate culture conditions. CONCLUSIONS Our results suggest that vitrification is a reliable and effective method for cryopreservation of HAMs. [ABSTRACT FROM AUTHOR]

BACKGROUND We investigated the differences in anthropometrical, hormonal and insulin resistance parameters according to the subtype of polycystic ovary syndrome (PCOS) in Korean women. METHODS We recruited 166 women with PCOS and retrospectively recruited 277 controls. PCOS was diagnosed by irregular menstruation (IM), polycystic ovary (PCO) and hyperandrogenism (HA). Subjects were divided into four subgroups: the IM/HA/PCO group (n = 87, 52.4%), the IM/PCO group (n = 52, 31.3%), the IM/HA group (n = 23, 13.9%) and the HA/PCO group (n = 4, 2.4%). Clinical and biochemical variables were compared among the PCOS subgroups. RESULTS The IM/HA/PCO and IM/HA groups showed higher body mass index (P P P P P P P = 0.004), diastolic BP (P = 0.001), fasting insulin (P P P P CONCLUSIONS Women with PCOS without HA are common in Korea and are less likely to have metabolic dysfunction, insulin resistance and elevated BP. PCOS without HA may be a mild phenotype of PCOS. Therefore, women with PCOS in Korea could have a reduced likelihood of having metabolic syndrome compared with women of other ethnicities. [ABSTRACT FROM AUTHOR]