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1.
Phys Chem Chem Phys ; 22(4): 2061-2072, 2020 Jan 28.
Article in English | MEDLINE | ID: mdl-31904067

ABSTRACT

CO2 expanded organic solvents possess significant advantages in liquid-phase exfoliation to obtain monolayer/few-layer graphene from graphite. Further insights into the mechanism of graphene exfoliation in such solvents are essential to explore liquid-phase dispersion of graphene as a more potent alternative to chemical vapor deposition. In this study, dynamic processes of exfoliation and stabilization of graphene in CO2-N,N-dimethylformamide (DMF), CO2-N-methylpyrrolidone (NMP), CO2-dimethyl sulfoxide (DMSO), and CO2-ethanol (EtOH) were investigated using molecular dynamics simulations. The origin of the effect of each solvent on graphene exfoliation was analyzed quantitatively through potential mean force simulations. It has been found that the organic solvent in a CO2 expanded solvent should be chosen with proper surface tension, and there exist two different graphene exfoliation processes in the effective solvents, which can be described as "burger dissociation" and "extrusion-taking away" processes, respectively. In the former process, a characteristic "super-burger-like" conformation with a semi-exfoliated structure was formed, which was the deciding factor to obtain high ratio of monolayer/few-layer graphene in dispersion product. A theoretical explanation has also been provided at the molecular level to the earlier experimental phenomena. A predicted simulation of the CO2-3,3'-iminobis(N,N-dimethylpropylamine) (DMPA) system is also calculated. This investigation helps to avoid incompatible CO2 expanded organic solvents employed in the experimental studies and provides theoretical clues to understand the mechanism of exfoliation and stabilization of graphene in such solvents.

2.
Waste Manag ; 102: 732-742, 2020 Feb 01.
Article in English | MEDLINE | ID: mdl-31805446

ABSTRACT

Industrial waste lignin was commonly burnt or discharged into river in the past. However, in this study, lignin has been converted into high value-added nano-biochar as a renewable reinforcing filler of styrene-butadiene rubber (SBR) by a simple high-temperature carbonization treatment. Herein, the physicochemical change in lignin before and after carbonization was investigated. It was found that lignin-derived biochar (LB) consisted of vesicle-like primary nanoparticles which were closely packed to form "high-structure" irregular fragments with a high specific surface area (83.41 m2/g). When incorporating LB into SBR, the tensile properties of LB/SBR composites were significantly improved. At the filler loading of 40 phr, the tensile strength and elongation at break of the rubber composite were improved up to 7.1-folds and 2.4-folds of pristine SBR, respectively. Compared to commercial carbon black (CB) N330, the LB showed a similar reinforcing effect on SBR. However, the analysis on the morphology, stress-strain behavior and dynamic mechanical behavior suggested distinct reinforcing mechanisms for LB- and CB-filled rubber composites, due to the difference in the surface properties and structural characteristic of fillers. This work showed the application potential of LB as a renewable substitute of CB in rubber industry and brought environmental and economic benefits for the disposal of lignin.


Subject(s)
Lignin , Soot , Butadienes , Charcoal , Elastomers , Rubber , Styrenes
3.
PLoS One ; 13(12): e0209309, 2018.
Article in English | MEDLINE | ID: mdl-30576349

ABSTRACT

Low FMR1 variants (CGGn<26) have been associated with premature ovarian aging, female infertility and poor IVF treatment success. Until now, there is little published information concerning possible molecular mechanisms for this effect. We wished to examine whether relative expression of RNA and the FMR1 gene's fragile X mental retardation protein (FMRP) RNA isoforms differ in women with various FMR1 sub-genotypes (normal, low CGGn<26 and/or high CGGn≥34). This prospective cohort study was conducted between 2014 and 2017 in a clinical research unit of the Center for Human Reproduction in New York City. The study involved a total of 98 study subjects, including 18 young oocyte donors and 80 older infertility patients undergoing routine in vitro fertilization (IVF) cycles. The main outcome measure was RNA expression in human luteinized granulosa cells of 5 groups of FMRP isoforms. The relative expression of FMR1 RNA in human luteinized granulosa cells was measured by real-time PCR and a possible association with CGGn was explored. All 5 groups of FMRP RNA isoforms examined were found to be differentially expressed in human luteinized granulosa cells. The relative expression of four FMR1 RNA isoforms showed significant differences among 6 FMR1 sub-genotypes. Women with at least one low allele expressed significantly lower levels of all 5 sets of FRMP isoforms in comparison to the non-low group. While it would be of interest to see whether FMRP is also decreased in the low-group we recognize that in recent years it has been increasingly documented that information flow of genetics may be regulated by non-coding RNA, that is, without translation to a protein product. We, thus, conclude that various CGG expansions of FMR1 allele may lead to changes of RNA levels and ratios of distinct FMRP RNA isoforms, which could regulate the translation and/or cellular localization of FMRP, affect the expression of steroidogenic enzymes and hormonal receptors, or act in some other epigenetic process and therefore result in the ovarian dysfunction in infertility.


Subject(s)
Fragile X Mental Retardation Protein/genetics , Infertility, Female/genetics , Primary Ovarian Insufficiency/genetics , 5' Untranslated Regions , Adult , Alleles , Amino Acid Sequence , Base Sequence , Cohort Studies , Female , Fertilization in Vitro , Fragile X Mental Retardation Protein/metabolism , Fragile X Syndrome/genetics , Gene Expression , Granulosa Cells/metabolism , Humans , Infertility, Female/etiology , Infertility, Female/metabolism , Ovarian Reserve/genetics , Primary Ovarian Insufficiency/etiology , Primary Ovarian Insufficiency/metabolism , Prospective Studies , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA/genetics , RNA/metabolism , Sequence Homology, Amino Acid , Trinucleotide Repeat Expansion
4.
Sci Rep ; 8(1): 6441, 2018 Apr 24.
Article in English | MEDLINE | ID: mdl-29691433

ABSTRACT

The typical conductive polymer of PEDOT:PSS has recently attracted intensive attention in thermoelectric conversion because of its low cost and low thermal conductivity as well as high electrical conductivity. However, compared to inorganic counterparts, the relatively poor thermoelectric performance of PEDOT:PSS has greatly limited its development and high-tech applications. Here, we report a dramatic enhancement in the thermoelectric performance of PEDOT:PSS by constructing unique composite films with graphene quantum dots (GQDs). At room temperature, the electrical conductivity and Seebeck coefficient of PEDOT:PSS/GQDs reached to 7172 S/m and 14.6 µV/K, respectively, which are 30.99% and 113.2% higher than those of pristine PEDOT:PSS. As a result, the power factor of the optimized PEDOT:PSS/GQDs composite is 550% higher than that of pristine PEDOT:PSS. These significant improvements are attributed to the ordered alignment of PEDOT chains on the surface of GQDs, originated from the strong interfacial interaction between PEDOT:PSS and GQDs and the separation of PEDOT and PSS phases. This study evidently provides a promising route for PEDOT:PSS applied in high-efficiency thermoelectric conversion.

5.
J Ovarian Res ; 11(1): 23, 2018 Mar 16.
Article in English | MEDLINE | ID: mdl-29548330

ABSTRACT

BACKGROUND: Highly Individualized Egg Retrieval (HIER), defined as age-specific early oocyte retrieval (ER), has been demonstrated to avoid premature luteinization in women ≥43. We here investigated whether HIER also applies to younger women with premature ovarian aging (POA), and what best lead follicle size should be for administration of ovulation-triggers. METHODS: Fifty-six women ≥43, and 37 POA patients underwent IVF cycles. Granulosa cells (GCs) were isolated, cultures were established, RNA was extracted and real-time PCR analyses performed, with gene expressions at mRNA level investigated for FSH receptor (FSHR), luteinizing hormone receptor (LHCPR), P450 aromatase (CYP19a1) and progesterone receptor (PGR). POA was defined by age < 40, FSH above 95%CI and/or AMH below 95%CI for age. Women ≥43 years were divided into very early retrieval (VER), with human chorionic gonadotropin (hCG) trigger at 13.5-15.5 mm, ER at 16.0-18.0 mm or standard retrievel (SR) at 18.5-20.5 mm; POA patients were divided into ER and SR. Pregnancy rates and and molecular markers of premature luteinization (PL) were main outcome measures. RESULTS: ER resulted in a significantly higher clinical pregnancy rate (16.7%) than VER (5.9%) or SR (6.7%; both P < 0.05). Molecular markers of PL were highest with SR and lowest with VER. In POA, ER improved pregnancy chances even more than in women ≥43 (7.7% with SR vs. 41.7% with ER), while also reducing molecular markers of PL. With low ovarian reserve (LOR), by avoiding PL, ER with hCG trigger at 16.0-18.0 mm, thus, improves clinical pregnancy rates at all ages. As VER demonstrated lowest molecular PL marker but equally poor pregnancy rates as SR, too early ovulation triggers, likely, result in cytoplasmatic immaturity. CONCLUSIONS: HIER is even more effective in POA patients than women above age 43, demonstrating that HIER should be further investigated going into even more advanced ages.


Subject(s)
Fertilization in Vitro , Luteinization , Oocyte Retrieval , Ovarian Reserve , Adult , Female , Granulosa Cells/metabolism , Humans , Menstrual Cycle , Middle Aged , Ovarian Follicle/cytology , Ovarian Follicle/metabolism , Pregnancy , Pregnancy Rate , Primary Ovarian Insufficiency
6.
Polymers (Basel) ; 10(7)2018 Jul 19.
Article in English | MEDLINE | ID: mdl-30960722

ABSTRACT

In this paper, a solvent vapor-induced phase separation (SVIPS) technique was used to create a porous structure in polyvinylidene fluoride/Multi-walled carbon nanotube (PVDF/MWNTs) composites with the aim of increasing the electrical conductivity through the incorporation of MWNTs while retaining a low thermal conductivity. By using the dimethylformamide/acetone mixture, porous networks could be generated in the PVDF/MWNTs composites upon the rapid volatilization of acetone. The electrical conductivity was gradually enhanced by the addition of MWNTs. At the same time, the thermal conductivity of the PVDF film could be retained at 0.1546 W·m-1·K-1 due to the porous structure being even by loaded with a high content of MWNTs (i.e., 15 wt.%). Thus, the Seebeck coefficient, power factor and figure of merit (ZT) were subsequently improved with maximum values of 324.45 µV/K, 1.679 µW·m-1·K-2, and 3.3 × 10-3, respectively. The microstructures, thermal properties, and thermoelectric properties of the porous PVDF/MWNTs composites were studied. It was found that the enhancement of thermoelectric properties would be attributed to the oxidation of MWNTs and the porous structure of the composites. The decrease of thermal conductivity and the increase of Seebeck coefficient were induced by the phonon scattering and energy-filtering effect. The proposed method was found to be facile and effective in creating a positive effect on the thermoelectric properties of composites.

7.
Reprod Biol Endocrinol ; 14(1): 49, 2016 Aug 24.
Article in English | MEDLINE | ID: mdl-27553622

ABSTRACT

BACKGROUND: Previously manual human embryology in many in vitro fertilization (IVF) centers is rapidly being replaced by closed embryo incubation systems with time-lapse imaging. Whether such systems perform comparably to manual embryology in different IVF patient populations has, however, never before been investigated. We, therefore, prospectively compared embryo quality following closed system culture with time-lapse photography (EmbryoScope™) and standard embryology. We performed a two-part prospectively randomized study in IVF (clinical trial # NCT92256309). Part A involved 31 infertile poor prognosis patients prospectively randomized to EmbryoScope™ and standard embryology. Part B involved embryos from 17 egg donor-recipient cycles resulting in large egg/embryo numbers, thus permitting prospectively alternative embryo assignments to EmbryoScope™ and standard embryology. We then compared pregnancy rates and embryo quality on day-3 after fertilization and embryologist time utilized per processed embryo. RESULTS: Part A revealed in poor prognosis patients no differences in day-3 embryo scores, implantation and clinical pregnancy rates between EmbryoScope™ and standard embryology. The EmbryoScope™, however, more than doubled embryology staff time (P < 0.0001). In Part B, embryos grown in the EmbyoScope™ demonstrated significantly poorer day-3 quality (depending on embryo parameter between P = 0.005 and P = 0.01). Suspicion that conical culture dishes of the EmbryoScope™ (EmbryoSlide™) may be the cause was disproven when standard culture dishes demonstrated no outcome difference in standard incubation. CONCLUSIONS: Though due to small patient numbers preliminary, this study raises concerns about the mostly uncontrolled introduction of closed incubation systems with time lapse imaging into routine clinical embryology. Appropriately designed and powered prospectively randomized studies appear urgently needed in well-defined patient populations before the uncontrolled utilization of these instruments further expands. TRIAL REGISTRATION: NCT02246309 Registered September 18, 2014.


Subject(s)
Embryo Transfer/methods , Fetoscopy/methods , Infertility, Female/therapy , Time-Lapse Imaging/methods , Adult , Embryo Culture Techniques , Embryo Implantation/physiology , Embryo Transfer/instrumentation , Female , Fertilization in Vitro/instrumentation , Fertilization in Vitro/methods , Fetoscopes , Fetoscopy/instrumentation , Follow-Up Studies , Humans , Infertility, Female/diagnosis , Pilot Projects , Pregnancy , Prognosis , Prospective Studies , Time-Lapse Imaging/instrumentation , Treatment Outcome
8.
Reprod Biomed Online ; 33(3): 370-5, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27390063

ABSTRACT

Outcome measures of IVF success, which account for effectiveness of IVF and perinatal outcome risks, have recently been described. The association between number of embryos transferred in average and poor-prognosis IVF patients, and the chances of having good or poor IVF and perinatal outcomes, was investigated. Good IVF and perinatal outcome was defined as the birth of a live, term, normal-weight infant (≥2500 g). Poor IVF and perinatal outcome was defined as no live birth or birth of a very low weight neonate (<1500 g) or severe prematurity (birth at <32 weeks gestation). Each neonate was analysed as a separate outcome. A total of 713 IVF cycles in 504 average and poor-prognosis patients from January 2010 to December 2013 were identified. The odds of having good IVF and perinatal outcomes increased by 28% for each additional embryo transferred. The odds of poor IVF and perinatal outcome decreased by 32% with an additional embryo transferred. The likelihood of live birth with good perinatal outcome in average- and poor-prognosis patients after IVF increases with additional embryos being transferred. These data add to recently reported evidence in favour of multiple embryo transfer in older women and those with average or poor IVF prognosis.


Subject(s)
Embryo Transfer/methods , Fertilization in Vitro , Infertility, Female/therapy , Adult , Age Factors , Female , Humans , Maternal Age , Odds Ratio , Pregnancy , Pregnancy Rate , Prognosis , Treatment Outcome
9.
J Transl Med ; 14(1): 172, 2016 06 10.
Article in English | MEDLINE | ID: mdl-27286817

ABSTRACT

BACKGROUND: Though outcome models have been proposed previously, it is unknown whether cutoffs in clinical pregnancy and live birth rates at all ages are able to classify in vitro fertilization (IVF) patients into good-, intermediate- and poor prognosis. METHODS: We here in 3 infertile patient cohorts, involving 1247, 1514 and 632 women, built logistic regression models based on 3 functional ovarian reserve (FOR) parameters, including (1) number of good quality embryos, (2) follicle stimulating hormone (FSH, mIU/mL) and (3) anti-Müllerian hormone (AMH, ng/mL), determining whether clinical pregnancy and live birth rates can discriminate between good, intermediate and poor prognosis patients. RESULTS: All models, indeed, allowed at all ages for separation by prognosis, though cut offs changed with age. In the embryo model, increasing embryo production resulted in linear improvement of IVF outcomes despite transfer of similar embryo numbers; in the FSH model outcomes and FSH levels related inversely, while the association of AMH followed a bell-shaped polynomial pattern, demonstrating "best" outcomes at mid-ranges. All 3 models demonstrated increasingly poor outcomes with advancing ages, though "best" AMH even above age 43 was still associated with unexpectedly good pregnancy and delivery outcomes. Excessively high AMH, in contrast, was at all ages associated with spiking miscarriage rates. CONCLUSIONS: At varying peripheral serum concentrations, AMH, thus, demonstrates hithero unknown and contradictory effects on IVF outcomes, deserving at different concentrations investigation as a potential therapeutic agent, with pregnancy-supporting and pregnancy-interrupting properties.


Subject(s)
Anti-Mullerian Hormone/metabolism , Embryo, Mammalian/cytology , Fertilization in Vitro , Follicle Stimulating Hormone/metabolism , Adult , Age Factors , Cohort Studies , Delivery, Obstetric , Female , Humans , Models, Biological , Pregnancy , Prognosis , Treatment Outcome
10.
J Steroid Biochem Mol Biol ; 158: 82-89, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26804970

ABSTRACT

Testosterone has in recent years been proven essential for normal growth and maturation of small growing follicles. Concomitantly, low functional ovarian reserve (LFOR), characterized by a small growing follicle pool, has been associated with low testosterone levels, which can be of ovarian and/or adrenal origin. In this study we, therefore, investigated whether peripheral sex steroid precursors and testosterone levels potentially reflect on adrenal function. In a retrospective cohort study of 355 consecutive infertile women, who presented to an academically affiliated fertility center in New York City, we investigated in a series of statistical models whether low peripheral sex steroid precursors and testosterone are associated with peripheral cortisol (C) levels, reflecting adrenal function. To determine potential correlations, we investigated the dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), androstenedione (AD), total testosterone (TT), free testosterone (FT); sex hormone binding globulin (SHBG), anti-Müllerian hormone (AMH), thyroid stimulating hormone (TSH) and C in a series of multivariate and logistic regression analyses, utilizing C either as a continuous variable or with cut off <5.0µg/dL, and TT only as a continuous variable. Practically all models demonstrated significant predictability of peripheral sex hormone precursors for C levels, with DHEA demonstrating the strongest and most consistent predictability as an individual parameter and as part of the DHEAS/DHEA ratio. We conclude that in infertile women peripheral sex hormone precursors, especially DHEA, reflect C levels and, therefore, adrenal function. In infertile women, at all ages low levels of sex hormone precursors, therefore, should be considered indications for further adrenal assessments.


Subject(s)
Androgens/blood , Hydrocortisone/blood , Infertility, Female/blood , Adult , Anti-Mullerian Hormone/blood , Female , Humans , Sex Hormone-Binding Globulin/analysis , Testosterone Congeners/blood , Thyrotropin/blood
11.
Endocrine ; 52(1): 165-71, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26419849

ABSTRACT

Rescue in vitro maturation (IVM) is currently not a routine procedure in association with in vitro fertilization (IVF). We compared in a prospectively cohort study of 10 patients with normal functional ovarian reserve (NFOR) and of 25 with low functional ovarian reserve (LFOR), defined by abnormally high FSH and/or abnormally low AMH levels), IVM dynamics of immature oocytes. Following controlled ovarian hyperstimulation in IVF cycles, only immature oocytes underwent rescue IVM (for up to 48 h). Oocyte maturation dynamics, fertilization rates, embryo development, and pregnancy rates were then compared between NFOR and LFOR patients. Though proportion of MI and GV oocytes reaching MII stages within 48 h and rate of maturation of MI oocytes did not differ, in women with LFOR significantly more GV oocytes reached MII stage within 24 h (30.4 vs. 66.9 %; P = 0.013), while fertilization rates and embryo generation numbers were similar between both groups. Rescue IVM, thus, produced 1.5 additional embryos for transfer in women with LFOR and 1.6 in patients with NFOR, a highly significant difference in relative improvement in available embryo numbers for LFOR (+60.0 %) and NFOR women (+16.5 %). Rescue IVM, thus, not only demonstrates different time dynamics between women with LFOR and NFOR but also disproportionate efficacy in improving available embryo numbers for transfer in favor of LFOR patients. 1/7 patients, who reached embryo transfer with only embryos produced via rescue IVF conceived and delivered, proving that rescue IVF in women with LFOR also improves pregnancy and delivery chances. Because of the small number of embryos LFOR patients produce, every additional embryo is of considerable potential clinical significance for them, suggesting that rescue IVM in women with LFOR should become routine practice.


Subject(s)
In Vitro Oocyte Maturation Techniques/methods , Ovarian Diseases/pathology , Ovarian Reserve , Adult , Cohort Studies , Embryo Transfer/methods , Embryonic Development , Female , Fertilization in Vitro , Follicle Stimulating Hormone/blood , Humans , Infertility, Female , Menstrual Cycle , Oocyte Retrieval , Ovulation Induction , Pregnancy , Prospective Studies
12.
PLoS One ; 10(12): e0143632, 2015.
Article in English | MEDLINE | ID: mdl-26630267

ABSTRACT

CONTEXT: Our center's quality improvement optimization process on many occasions anecdotally suggested that oocyte assessments might enhance embryo assessment in predicting pregnancy chances with in vitro fertilization (IVF). OBJECTIVE: To prospectively compare a morphologic oocyte grading system to standard day-3 morphologic embryo assessment. DESIGN, SETTING, PATIENTS: We prospectively investigated in a private academically-affiliated infertility center 94 consecutive IVF cycles based on 6 criteria for oocyte quality: morphology, cytoplasm, perivitelline space (PVS), zona pellucida (ZP), polar body (PB) and oocyte size, each assigned a value of -1 (worst), 0 (average) or +1 (best), so establishing an average total oocyte score (TOS). Embryo assessment utilized grade and cell numbers of each embryo on day-3 after oocyte retrieval. Clinical pregnancy was defined by presence of at least one intrauterine gestational sac. INTERVENTIONS: Standard IVF cycles in infertile women. MAIN OUTCOME MEASURES: Predictability of pregnancy based on oocyte and embryo-grading systems. RESULTS: Average age for all patients was 36.5 ± 7.3 years; mean oocyte yield was 7.97± 5.76; Patient specific total oocyte score (PTOS) was -1.05 ± 2.24. PTOS, adjusted for patient age, was directly related to odds of increased embryo cell numbers (OR 1.12, P = 0.025), embryo grade (OR 1.19, P < 0.001) and clinical pregnancy [OR 1.58 (95%CI 1.23 to 2.02), P < 0.001]. Restricting the analysis to day three embryos of high quality (8-cell/ good grades), TOS was still predictive of clinical pregnancy (OR 2.08 (95%CI 1.26 to 3.44, P = 0.004). Among the 69 patients with embryos of Grade 4 or better available for transfer 23 achieved Clinical Pregnancy. When the analysis was restricted to the 69 transfers with good quality embryos (≥ Grade 4) the Oocyte Scoring System (TOS) (AUC±SE 0.863±0.044, oocyte score) provided significantly greater predictive value for clinical pregnancy compared to the embryo grade alone (AUC 0.646 ± 0.072, embryo grade) p = 0.015. CONCLUSIONS: Oocyte-scoring, thus, provides useful clinical information especially in good prognosis patients with large numbers of high quality embryos. This finding appears of particular importance at a time when many IVF centers are committing sizable investments to closed incubation systems with time-lapse photography, which are exclusively meant to define embryo morphology.


Subject(s)
Embryo, Mammalian/embryology , Fertilization in Vitro/standards , Oocytes/physiology , Adult , Female , Humans , Pregnancy , Treatment Outcome
13.
J Endocrinol ; 226(3): 167-80, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26264981

ABSTRACT

Why IVF pregnancy rates decline sharply after age 43 is unknown. In this study, we compared granulosa cell (GC) function in young oocyte donors (n=31, ages 21-29), middle-aged (n=64, ages 30-37) and older infertile patients (n=41, ages 43-47). Gene expressions related to gonadotropin activity, steroidogenesis, apoptosis and luteinization were examined by real-time PCR and western blot in GCs collected from follicular fluid. FSH receptor (FSHR), aromatase (CYP19A1) and 17ß-hydroxysteroid dehydrogenase (HSD17B) expression were found down regulated with advancing age, while LH receptor (LHCGR), P450scc (CYP11A1) and progesterone receptor (PGR) were up regulated. Upon in vitro culture, GCs were found to exhibit lower proliferation and increased apoptosis with aging. While FSH supplementation stimulated GCs growth and prevented luteinization in vitro. These observations demonstrate age-related functional declines in GCs, consistent with premature luteinization. To avoid premature luteinization in women above age 43, we advanced oocyte retrieval by administering human chorionic gonadotropin at maximal leading follicle size of 16  mm (routine 19-21  mm). Compared to normal cycles in women of similar age, earlier retrieved patients demonstrated only a marginal increase in oocyte prematurity, yet exhibited improved embryo numbers as well as quality and respectable clinical pregnancy rates. Premature follicular luteinization appears to contribute to rapidly declining IVF pregnancy chances after age 43, and can be avoided by earlier oocyte retrieval.


Subject(s)
Aging/physiology , Granulosa Cells/physiology , Luteinization/physiology , Oocyte Retrieval/methods , 17-Hydroxysteroid Dehydrogenases/genetics , 17-Hydroxysteroid Dehydrogenases/metabolism , Adult , Age Factors , Aromatase/genetics , Aromatase/metabolism , Down-Regulation , Female , Gene Expression Regulation , Humans , Middle Aged , Pregnancy , Receptors, FSH/genetics , Receptors, FSH/metabolism , Receptors, LH/genetics , Receptors, LH/metabolism , Receptors, Progesterone/genetics , Receptors, Progesterone/metabolism , Up-Regulation , Young Adult
14.
Transl Res ; 166(5): 502-7.e1-2, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26209748

ABSTRACT

Mouse fmr1 models, and recent cross-sectional human data, suggest that different triple CGGn ranges of the fragile X mental retardation 1 (FMR1) gene are associated with variations in ovarian aging and infertility treatment outcomes. The FMR1 mutation affecting reproductive function most negatively in humans is the so-called low mutation, characterized by CGGn < 26. We here present a first longitudinal study of selected young women with normal functional ovarian reserve (FOR). In a prospective cohort study, we selected among 233 young oocyte donors (mean age 24.8 ± 3.3 years) as study population of 66 who had more than 1 anti-Müllerian hormone (AMH) level drawn over a 4-year period. AMH curves, as reflection of FOR, were then statistically compared between women with and without low FMR1 alleles. Biallelic low FMR1 (hom-low/low) donors already at initial presentation demonstrated significantly lower FOR than donors with biallelic normal (norm) FMR1 (CGGn = 26-34; P = 0.001). Although monoallelic low FMR1 at initial presentation was not yet associated with decreased FOR, it over 4 years did demonstrate significantly enhanced declines in FOR (P = 0.046). Including repeat measurements, low/low (P = 0.006) and high/high (CGGn > 34) alleles (P < 0.001) demonstrated lower FOR by AMH than norm donors. Even monoallelic low FMR1 alleles are, thus, already at young female ages associated with accelerated declines in FOR. Low FMR1 alleles, therefore, potentially represent a screening tool for women at genetic risk toward premature ovarian senescence, representing in all races circa 10% of the female population.


Subject(s)
Alleles , Fragile X Mental Retardation Protein/genetics , Ovarian Reserve/genetics , Adult , Female , Humans , Young Adult
15.
Reprod Biol Endocrinol ; 13: 29, 2015 Apr 11.
Article in English | MEDLINE | ID: mdl-25889294

ABSTRACT

BACKGROUND: In successful reproduction, endocrine and immune systems closely interact. We here attempt to further elucidate the relationship between androgen levels, systemic activation of the immune system and reproductive success in infertile women, utilizing 2 distinct infertile patient cohorts. METHODS: In Group 1, we investigated 322 women (ages 38.6+/-5.4 years) at initial presentation; in Group 2 125 women undergoing in vitro fertilization (169 IVF cycles, ages 38.9+/-5.5 years). In Group 1, we assessed androgens and an immune panel, previously demonstrated to discriminate between activated quiescent immune systems; in Group 2, utilizing the same immune panel, we investigated whether immune system activation relates to embryo quality in IVF cycles. RESULTS: No individual immune test within the immune panel was associated with androgen levels. The total/free testosterone ratio (TT/FT) was, however, significantly associated with presence of gammopathies (in IgG, IgM, IgA, IgE; P=0.026). Surprisingly, immune system activation was associated with significantly improved embryo quality (P=0.008), a finding persistent after adjustment for age and repeat IVF cycles (P=0.006). CONCLUSIONS: Association of immune system activation with improved embryo quality concurs with previously reported immune activation in association with normal functional ovarian reserve (FOR) and normal androgen levels, while, counter intuitively, hypoandrogenism and low FOR are associated with lack of immune system activation. Mild immune system activation, therefore, likely appears essential for establishment of pregnancy, and may be regulated by androgens.


Subject(s)
Endocrine System/physiology , Immune System/physiology , Infertility, Female/immunology , Reproduction/immunology , Adult , Androgens/blood , Cohort Studies , Embryo, Mammalian/physiology , Female , Fertilization in Vitro , Humans , Immune System Phenomena , Pregnancy , Pregnancy Rate
16.
PLoS One ; 9(7): e102274, 2014.
Article in English | MEDLINE | ID: mdl-25019151

ABSTRACT

CONTEXT: Mutations of the fragile X mental retardation 1 (FMR1) gene are associated with distinct ovarian aging patterns. OBJECTIVE: To confirm in human in vitro fertilization (IVF) that FMR1 affects outcomes, and to determine whether this reflects differences in ovarian aging between FMR1 mutations, egg/embryo quality or an effect on implantation. DESIGN, SETTING, PATIENTS: IVF outcomes were investigated in a private infertility center in reference to patients' FMR1 mutations based on a normal range of CGG(n = 26-34) and sub-genotypes high (CGG(n>34)) and low (CGG(<26)). The study included 3 distinct sections and study populations: (i) A generalized mixed-effects model of morphology (777 embryos, 168 IVF cycles, 125 infertile women at all ages) investigated whether embryo quality is associated with FMR1; (ii) 1041 embryos in 149 IVF cycles in presumed fertile women assessed whether the FMR1 gene is associated with aneuploidy; (iii) 352 infertile patients (< age 38; in 1st IVF cycles) and 179 donor-recipient cycles, assessed whether the FMR1 gene affects IVF pregnancy chances via oocyte/embryo quality or non-oocyte maternal factors. INTERVENTIONS: Standardized IVF protocols. MAIN OUTCOME MEASURES: Morphologic embryo quality, ploidy and pregnancy rates. RESULTS: (i) Embryo morphology was reduced in presence of a low FMR1 allele (P = 0.032). In absence of a low allele, the odds ratio (OR) of chance of good (vs. fair/poor) embryos was 1.637. (ii) FMR1 was not associated with aneuploidy, though aneuploidy increased with female age. (iii) Recipient pregnancy rates were neither associated with donor age or donor FMR1. In absence of a low FMR1 allele, OR of clinical pregnancy (vs. chemical or no pregnancy) was 2.244 in middle-aged infertility patients. CONCLUSIONS: A low FMR1 allele (CGG(<26)) is associated with significantly poorer morphologic embryo quality and pregnancy chance. As women age, low FMR1 alleles affect IVF pregnancy chances by reducing egg/embryo quality by mechanisms other than embryo aneuploidy.


Subject(s)
Embryo, Mammalian/physiology , Fertilization in Vitro/methods , Fragile X Mental Retardation Protein/genetics , Genetic Markers/genetics , Infertility/therapy , Aneuploidy , Female , Humans , Mutation/genetics , Odds Ratio , Ovary/growth & development , Pregnancy , Pregnancy Rate , Treatment Outcome
17.
PLoS One ; 9(7): e102370, 2014.
Article in English | MEDLINE | ID: mdl-25036526

ABSTRACT

Previously reported findings in Austrian BRCA1/2 mutation carriers suggested a possible dependency of embryos with BRCA1/2 mutations on so-called low alleles of the fragile X mental retardation 1 (FMR1) gene, characterized by less than 26 CGG repeats (CGG(n<26)). The hypothesis arose from a study reporting highly statistically significant enrichment of low FMR1 alleles, significantly exceeding low allele prevalence in a general population, suggesting embryo lethality of BRCA1/2 mutations, "rescued" by presence of low FMR1 alleles. Such a dependency would also offer an explanation for the so-called "BRCA-paradox," characterized by BRCA1/2 deficient embryonic tissues being anti-proliferative (thereby potentially causing embryo-lethality) but proliferative in malignant tumors, including breast and ovarian cancers. Follow up investigations by other investigators, however, at most demonstrated trends towards enrichment but, mostly, no enrichment at all, raising questions about the original observation and hypothesis. We in this study, therefore, investigated CGGn of the FMR1 gene of 86 anonymized DNA samples from women with various forms of ovarian cancer, and were unable to demonstrate differences in prevalence of low FMR1 alleles either between positive and negative ovarian cancer patients for BRCA1/2 or between ovarian cancer patients and reported rates in non-cancer populations. This raises further questions about a suggested dependency between BRCA1/2 and FMR1, but also raises the possibility that investigated Austrian BRCA1/2 carrier populations differ from those in other countries. Either only selected BRCA1/2 mutations, therefore, interact with low FMR1 alleles or the Austrian data reflect only coincidental observations.


Subject(s)
BRCA1 Protein/genetics , BRCA2 Protein/genetics , Fragile X Mental Retardation Protein/genetics , Ovarian Neoplasms/genetics , Alleles , Case-Control Studies , Female , Genetic Predisposition to Disease/genetics , Genotype , Humans , Mutation
18.
Mol Cell Biol ; 33(15): 2817-28, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23689136

ABSTRACT

Androgens play a major role in the regulation of normal ovarian function; however, they are also involved in the development of ovarian pathologies. These contrasting effects may involve a differential response of granulosa cells to the androgens testosterone (T) and dihydrotestosterone (DHT). To determine the molecular pathways that mediate the distinct effects of T and DHT, we studied the expression of the liver receptor homolog 1 (LRH-1) gene, which is differentially regulated by these steroids. We found that although both T and DHT stimulate androgen receptor (AR) binding to the LRH-1 promoter, DHT prevents T-mediated stimulation of LRH-1 expression. T stimulated the expression of aryl hydrocarbon receptor (AHR) and its interaction with the AR. T also promoted the recruitment of the AR/AHR complex to the LRH-1 promoter. These effects were not mimicked by DHT. We also observed that the activation of extracellular regulated kinases by T is required for AR and AHR interaction. In summary, T, but not DHT, stimulates AHR expression and the interaction between AHR and AR, leading to the stimulation of LRH-1 expression. These findings could explain the distinct response of granulosa cells to T and DHT and provide a molecular mechanism by which DHT negatively affects ovarian function.


Subject(s)
Gene Expression Regulation , Granulosa Cells/metabolism , Receptors, Androgen/metabolism , Receptors, Aryl Hydrocarbon/metabolism , Receptors, Cytoplasmic and Nuclear/genetics , Testosterone/metabolism , Animals , Cells, Cultured , Dihydrotestosterone/metabolism , Female , MAP Kinase Signaling System , Promoter Regions, Genetic , Rats , Rats, Sprague-Dawley
19.
Mol Endocrinol ; 27(3): 511-23, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23340251

ABSTRACT

FSH and IGF-I synergistically stimulate gonadal steroid production; conversely, silencing the FSH or the IGF-I genes leads to infertility and hypogonadism. To determine the molecular link between these hormones, we examined the signaling cross talk downstream of their receptors. In human and rodent granulosa cells (GCs), IGF-I potentiated the stimulatory effects of FSH and cAMP on the expression of steroidogenic genes. In contrast, inhibition of IGF-I receptor (IGF-IR) activity or expression using pharmacological, genetic, or biochemical approaches prevented the FSH- and cAMP-induced expression of steroidogenic genes and estradiol production. In vivo experiments demonstrated that IGF-IR inactivation reduces the stimulation of steroidogenic genes and follicle growth by gonadotropins. FSH or IGF-I alone stimulated protein kinase B (PKB), which is also known as AKT and in combination synergistically increased AKT phosphorylation. Remarkably, blocking IGF-IR expression or activity decreased AKT basal activity and abolished AKT activation by FSH. In GCs lacking IGF-IR activity, FSH stimulation of Cyp19 expression was rescued by overexpression of constitutively active AKT. Our findings demonstrate, for the first time, that in human, mouse, and rat GCs, the well-known stimulatory effect of FSH on Cyp19 and AKT depends on IGF-I and on the expression and activation of the IGF-IR.


Subject(s)
Follicle Stimulating Hormone/pharmacology , Gene Expression Regulation/drug effects , Granulosa Cells/enzymology , Insulin-Like Growth Factor I/metabolism , Proto-Oncogene Proteins c-akt/genetics , Signal Transduction , Steroids/metabolism , Animals , Cell Differentiation/drug effects , Cyclic AMP Response Element-Binding Protein/metabolism , Enzyme Activation/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , Female , Granulosa Cells/cytology , Granulosa Cells/drug effects , HEK293 Cells , Humans , Mice , Phosphorylation/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Sprague-Dawley , Receptor, IGF Type 1/metabolism , Receptors, FSH/metabolism , Signal Transduction/drug effects , Species Specificity
20.
Endocrinology ; 153(5): 2474-85, 2012 May.
Article in English | MEDLINE | ID: mdl-22434075

ABSTRACT

Single GATA-6 (G6(gcko)), GATA-4 (G4(gcko)), and double GATA-4/6 (G4/6(gcko)) granulosa cell-specific knockout mice were generated to further investigate the role of GATA transcription factors in ovarian function in vivo. No reproductive defects were found in G6(gcko) animals. G4(gcko) animals were subfertile as indicated by the reduced number of pups per litter and the release of significantly fewer oocytes at ovulation. In marked contrast, G4/6(gcko) females fail to ovulate and are infertile. Furthermore, G4/6(gcko) females had irregular estrous cycles, which correlate with the abnormal ovarian histology found in unstimulated adult G4/6(gcko) females showing lack of follicular development and increased follicular atresia. Moreover, treatment with exogenous gonadotropins did not rescue folliculogenesis or ovulation in double-knockout G4/6(gcko) mice. In addition, ovary weight and estradiol levels were significantly reduced in G4(gcko) and G4/6(gcko) animals when compared with control and G6(gcko) mice. Aromatase, P450scc, and LH receptor expression was significantly lower in G4(gcko) and G4/6(gcko) mice when compared with control animals. Most prominently, FSH receptor (FSHR) protein was undetectable in granulosa cells of G4(gcko) and G4/6(gcko). Accordingly, gel shift and reporter assays revealed that GATA-4 binds and stimulates the activity of the FSHR promoter. These results demonstrate that GATA-4 and GATA-6 are needed for normal ovarian function. Our data are consistent with a role for GATA-4 in the regulation of the FSHR gene and provide a possible molecular mechanism to explain the fertility defects observed in animals with deficient GATA expression in the ovary.


Subject(s)
GATA4 Transcription Factor/genetics , GATA6 Transcription Factor/genetics , Granulosa Cells/metabolism , Infertility, Female/genetics , Ovarian Follicle/metabolism , Ovulation/genetics , Receptors, FSH/genetics , Animals , Female , GATA4 Transcription Factor/metabolism , GATA6 Transcription Factor/metabolism , Infertility, Female/metabolism , Mice , Mice, Knockout , Ovulation/metabolism , Receptors, FSH/metabolism , Receptors, LH/genetics , Receptors, LH/metabolism
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