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1.
Opt Lett ; 49(15): 4449-4452, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090956

RESUMEN

In this study, we investigate the unidirectional self-imaging phenomenon in the shifted photonic crystal (PC) heterostructure. A spin-locked topological edge state, which originates from the mismatch of the Wannier center positions, can propagate along the shifted PC interface without backscattering. When the neighboring shifted PC interfaces are close enough, the coupling between the edge states happens, and coupled edge states (CES) can be found. Based on the finite element method (FEM) simulation, the spin-locked multimode interference (MMI) and self-imaging phenomenon of CES, including paired and symmetrical interference, are achieved in multiple shifted PC interfaces. To illustrate the application of the frequency splitters, the T-shaped and double cross-shaped structures with backscattering immunity and spin-locked characteristics are proposed. Our work provides an alternative way toward the design of a topological splitter by utilizing the photonic frequency and spin degrees of freedom at the same time.

2.
Hum Reprod ; 37(8): 1795-1805, 2022 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-35595223

RESUMEN

STUDY QUESTION: Is a dual ovulation trigger with a combination of GnRH agonist (GnRHa) and hCG superior to single hCG and/or single GnRHa trigger in improving treatment outcomes in advanced-age women (aged ≥ 35 years) undergoing IVF/ICSI treatment? SUMMARY ANSWER: Co-administration of GnRHa and hCG as a dual trigger increases the number of good-quality embryos but it is not associated with a higher number of oocytes retrieved, compared with single hCG or GnRHa trigger. WHAT IS KNOWN ALREADY: Many studies have demonstrated that a dual trigger has positive impact on oocyte maturation, retrieval rate and pregnancy rate without increasing the risk of ovarian hyperstimulation syndrome (OHSS) in some groups of IVF patients, when compared with single hCG trigger. Few studies have however been conducted to compare a dual trigger with a single GnRHa trigger, and insufficient evidence exists to support which trigger can achieve the best outcomes in IVF patients aged ≥35 years. STUDY DESIGN, SIZE, DURATION: This was an open-label randomized controlled trial of 510 participants conducted at single reproductive medical center from January 2019 to December 2021. After a sample size calculation performed by retrospectively analyzing our previous clinical data, we planned to recruit 170 patients in each group and 510 patients in total for the study. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women aged ≥35 years undergoing IVF/ICSI treatment, receiving a non-pituitary down-regulation protocol, and with low risk of OHSS, were enrolled in this trial. On the trigger day, patients were randomized into three groups: hCG alone (who received 6000 IU of hCG), GnRHa alone (who received 0.2 mg of triptorelin) and dual trigger (who received 0.2 mg of triptorelin plus 2000 IU of hCG) groups. The primary outcome parameter was the number of retrieved oocytes. The secondary outcome parameters included, among others, the number and rates of mature oocytes, two pronuclei (2PN) embryos and good-quality embryos, as the rates of OHSS, clinical pregnancy, miscarriage and live birth. MAIN RESULTS AND THE ROLE OF CHANCE: There were no significant differences in the baseline demographic characteristics among the three groups. The dual trigger was associated with a higher retrieval rate (87.9% vs 84.1% in the hCG group, P = 0.031; 87.9% vs 83.6% in the GnRHa group, P = 0.014). However, the number of retrieved oocytes in the dual trigger group was comparable with those in the hCG group (4.08 ± 2.79 vs 3.60 ± 2.71, P = 0.080) and the GnRHa group (4.08 ± 2.79 vs 3.81 ± 3.38, P = 0.101); comparable data between the groups were also found when analyzing the number of 2PN embryos and the 2PN rate. In the dual trigger group, the numbers of good-quality embryos and viable embryos were both significantly higher than in the hCG group (1.74 ± 1.90 vs 1.19 ± 1.45, P = 0.016 and 2.19 ± 2.11 vs 1.56 ± 1.66, P = 0.008, respectively) and the GnRHa group (1.74 ± 1.90 vs 1.20 ± 1.67, P = 0.003 and 2.19 ± 2.11 vs 1.45 ± 1.75, P = 0.001, respectively). Pregnancy outcomes after fresh embryo transfer (ET) were comparable between the groups. The live birth rate and ongoing pregnancy rate after frozen ET in the dual trigger group were significantly higher than those in the GnRHa group (32.6% vs 14.1%, P = 0.007 and 34.8% vs 17.6%, P = 0.013, respectively), but not superior to those in the hCG group (32.6% vs 27.9%, P = 0.537 and 34.8% vs 27.9%, P = 0.358, respectively). LIMITATIONS, REASONS FOR CAUTION: Women of advanced age are quite a heterogeneous population and overlap with poor ovarian responders or patients with diminished ovarian reserve. We therefore could not entirely exclude selection biases or confounding factors. This study was also not a double-blinded trial; the patients in the GnRHa and dual trigger groups could have been affected by the placebo effect. WIDER IMPLICATIONS OF THE FINDINGS: The results of this study suggest that in advanced-age women with low risk of OHSS, a dual trigger or even a single hCG trigger may be a better choice than a single GnRHa trigger. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the Shanghai Municipal Health Commission of Science and Research Fund (20184Y0289). The authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: This trial was registered in the Chinese Clinical Trial Registry (ChiCTR-1800016285). TRIAL REGISTRATION DATE: 24 May 2018. DATE OF FIRST PATIENT'S ENROLMENT: 2 January 2019.


Asunto(s)
Gonadotropina Coriónica , Hormona Liberadora de Gonadotropina , Inducción de la Ovulación , China , Gonadotropina Coriónica/administración & dosificación , Femenino , Fertilización In Vitro/métodos , Hormona Liberadora de Gonadotropina/agonistas , Humanos , Síndrome de Hiperestimulación Ovárica/prevención & control , Ovulación , Inducción de la Ovulación/métodos , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Inyecciones de Esperma Intracitoplasmáticas/métodos , Pamoato de Triptorelina/administración & dosificación
3.
J Cell Mol Med ; 25(12): 5404-5416, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33955677

RESUMEN

Gestational and postpartum high-fat diets (HFDs) have been implicated as causes of obesity in offspring in later life. The present study aimed to investigate the effects of gestational and/or postpartum HFD on obesity in offspring. We established a mouse model of HFD exposure that included gestation, lactation and post-weaning periods. We found that gestation was the most sensitive period, as the administration of a HFD impaired lipid metabolism, especially fatty acid oxidation in both foetal and adult mice, and caused obesity in offspring. Mechanistically, the DNA hypermethylation level of the nuclear receptor, peroxisome proliferator-activated receptor-α (Pparα), and the decreased mRNA levels of ten-eleven translocation 1 (Tet1) and/or ten-eleven translocation 2 (Tet2) were detected in the livers of foetal and adult offspring from mothers given a HFD during gestation, which was also associated with low Pparα expression in hepatic cells. We speculated that the hypermethylation of Pparα resulted from the decreased Tet1/2 expression in mothers given a HFD during gestation, thereby causing lipid metabolism disorders and obesity. In conclusion, this study demonstrates that a HFD during gestation exerts long-term effects on the health of offspring via the DNA demethylation of Pparα, thereby highlighting the importance of the gestational period in regulating epigenetic mechanisms involved in metabolism.


Asunto(s)
Desmetilación , Dieta Alta en Grasa/efectos adversos , Obesidad/patología , PPAR alfa/metabolismo , Efectos Tardíos de la Exposición Prenatal/patología , Animales , Femenino , Edad Gestacional , Metabolismo de los Lípidos , Ratones , Ratones Endogámicos C57BL , Obesidad/etiología , Obesidad/metabolismo , PPAR alfa/genética , Embarazo , Efectos Tardíos de la Exposición Prenatal/etiología , Efectos Tardíos de la Exposición Prenatal/metabolismo
4.
J Steroid Biochem Mol Biol ; 206: 105806, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33340681

RESUMEN

Polycystic ovary syndrome (PCOS) is a heterogeneous disease defined by the presence of at least two of the following features: hyperandrogenism, oligoanovulation (OA), and polycystic ovarian morphology (PCOM). Hyperandrogenism is considered the cornerstone of PCOS. However, the most prevalent phenotype in Chinese women with PCOS is OA + PCOM [normo-androgenic PCOS (NA-PCOS)]. It has been reported that PCOS women have higher androgen levels in follicular fluid (FF), but whether NA-PCOS women have the same intrafollicular steroid profiles as hyperandrogenic PCOS (HA-PCOS) women has not been explored. In this study, we analyzed 17 steroids in stimulated size-matched ovarian follicles (16-18 mm) from 166 controls and 141 PCOS women [87 NA-PCOS and 54 HA-PCOS women, defined by a single serum testosterone (T) immunoassay measurement] using liquid chromatography tandem mass spectrometry, and investigated their relationship with baseline characteristics. No significant differences in intrafollicular steroid levels and product/precursor ratios between NA-PCOS and HA-PCOS women were observed, though HA-PCOS women had significantly higher serum luteinizing hormone and T levels than NA-PCOS women. NA-PCOS and HA-PCOS women had significantly higher levels of androstenedione (AD), T and free androgen index, higher enzyme activity of P450c17 (AD/17OH-progesterone), 3ßHSD2 (17OH-progesterone /17OH-pregnenolone) and P450c11 (corticosterone /11-deoxycorticosterone), lower levels of pregnenolone, 17OH-pregnenolone and 11-deoxycorticosterone, and decreased enzyme activity of P450aro (estrone/AD and estradiol/T) and 5α-reductase (dihydrotestosterone/T) in FF than controls. NA-PCOS women had significantly higher intrafollicular cortisol levels and lower 11ßHSD2 (cortisone/cortisol) activity than controls. Baseline serum T levels were slightly correlated with intrafollicular estrogens (E1: r = 0.192, p = 0.019; E2: r = 0.248, p = 0.002; E3: r = 0.248, p = 0.002) and androgens (DHEAS: r = 0.276, p = 0.001; AD: r = 0.185, p = 0.032; T: r = 0.173, p = 0.044) in controls and PCOS women respectively. Serum anti-Müllerian hormone (AMH) levels and antral follicle count (AFC) were correlated with intrafollicular cortisol (AMH: r = 0.380, p = 0.000; AFC: r = 0.177, p = 0.036) and corticosterone (AMH: r = 0.212, p = 0.048; AFC: r = 0.219, p = 0.009) levels in PCOS women. In conclusion, NA-PCOS and HA-PCOS women had statistically similar steroid metabolome profiles in FF, both of which showed a generally decreased steroidogenesis and hyperandrogenism compared to controls.


Asunto(s)
Hiperandrogenismo/sangre , Metaboloma/genética , Síndrome del Ovario Poliquístico/sangre , Esteroides/sangre , Adulto , Andrógenos/sangre , Androstenodiona/sangre , Hormona Antimülleriana , Estradiol/sangre , Estrógenos/sangre , Femenino , Líquido Folicular/metabolismo , Humanos , Hidrocortisona/sangre , Hiperandrogenismo/genética , Hiperandrogenismo/metabolismo , Hiperandrogenismo/patología , Hormona Luteinizante/sangre , Folículo Ovárico/metabolismo , Folículo Ovárico/patología , Síndrome del Ovario Poliquístico/genética , Síndrome del Ovario Poliquístico/metabolismo , Síndrome del Ovario Poliquístico/patología , Esteroides/metabolismo , Testosterona/sangre , Adulto Joven
5.
Oncotarget ; 9(37): 24627-24641, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29872493

RESUMEN

High androgen level impairs endometrial receptivity in women experiences the recurrent miscarriage. The mechanism of androgen actions on endometrium is still uncertain. We hypothesized that androgen has a direct effect on the endometrium in women with recurrent miscarriage. In the present study, we assess the impact of androgen (A2) at high concentration (10-7 M) on Ishikawa cells compared with the physiological concentration of androgen (10-9 M). To go into deeper analysis, we use global stable isotopes labeled profiling tactic using iTRAQ reagents, followed by 2D LC-MS/MS. We determine 175 non-redundant proteins, and 18 of these were quantified. The analysis of differentially expressed proteins (DEPs) identified 8 up-regulated proteins and 10 down-regulated in the high androgen group. These DEPs were examined by ingenuity pathway (IPA) analysis and established that these proteins might play vital roles in recurrent miscarriage and endometrium receptivity. In addition, proteins cyclin-dependent kinase inhibitor 2a (CDKN2a), endothelial protein C receptor (EPCR), armadillo repeat for velocardiofacial (ARVCF) were independently confirmed using western blot. Knockdown of CDKN2a significantly decreased the expression level of CDKN2a protein in ishikawa cells, and decreased migration (p < 0.01), invasion (p < 0.05), proliferation (p < 0.05), and the rate of Jar spheroid attachment (p < 0.05) to Ishikawa cell monolayer. The present results suggest that androgen at high concentration could alter the expression levels of proteins related to endometrium development and embryo implantation, which might be a cause of the impaired endometrial receptivity and miscarriage.

6.
Epigenetics Chromatin ; 11(1): 20, 2018 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-29801514

RESUMEN

BACKGROUND: The existing reports about intergenerational or transgenerational effects of intrauterine hyperglycemia have included both intrauterine and postnatal metabolic exposure factors, while the impact of intrauterine hyperglycemia per se has not been assessed alone. A number of studies suggest DNA methylation reprogramming of gametes plays a crucial role in the metabolic inheritance, but it is unclear when and how DNA methylation patterns are altered when exposed to intrauterine hyperglycemia. In this study, we selected nondiabetic F1- and F2-gestational diabetes mellitus (GDM) male mice as founders to examine metabolic changes in the next generation and performed methylome sequencing of day 13.5 primordial germ cells (PGCs) from F1-GDM to explore the underlying epigenetic mechanism. RESULTS: We found that intrauterine hyperglycemia exposure resulted in obesity, insulin resistance, and/or glucose intolerance in F2 male mice, but no metabolic changes in F3 male mice at 8 weeks. Using reduced representation bisulfite sequencing, we found DNA methylome of day 13.5 PGCs from F1-GDM fetuses revealed differently methylated genes enriched in obesity and diabetes. Methylation validation of the insulin resistance and fat accumulation gene Fyn showed a consistent hypomethylation status in F1 PGCs, F1 fetal testes, sperm from F1/C-GDM mice, and somatic cells from F2-GDM male mice. In contrast, no methylation alteration was observed in F2-GDM male germ cells and F3-GDM somatic cells. CONCLUSION: We provide evidence that intrauterine hyperglycemia exposure per se contributes to intergenerational metabolic changes in the F2 but not F3 generation. And the aberrant DNA methylation reprogramming occurs as early as day 13.5 in PGCs of the F1 generation. Our findings suggest that intrauterine exposure alone is sufficient to cause the epigenetic inheritance in F2 offspring, and the epigenetic memory carried by DNA methylation pattern could be erased by the second wave of methylation reprogramming in F2 PGCs during fetal development.


Asunto(s)
Metilación de ADN , Diabetes Gestacional/genética , Redes Reguladoras de Genes , Intolerancia a la Glucosa/genética , Obesidad/genética , Efectos Tardíos de la Exposición Prenatal/genética , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Epigénesis Genética , Femenino , Efecto Fundador , Predisposición Genética a la Enfermedad , Células Germinativas/citología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Resistencia a la Insulina , Masculino , Ratones , Embarazo , Proteínas Proto-Oncogénicas c-fyn/genética , Análisis de Secuencia de ADN
7.
Oncotarget ; 8(32): 53450-53464, 2017 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-28881823

RESUMEN

Maternal obesity influence the child's long-term development and health. Though, the mechanism concerned in this process is still uncertain. In the present study, we explored whether overfeeding of a high-fat diet during pregnancy in female rats altered metabolic phenotypes in an F1 generation and authenticated the contribution of hypothalamic leptin signaling. Leptin responsiveness and the number of immunopositive neurons for phosphorylated signal transducer and activator transcription 3 (pSTAT3) were analyzed. Neuropeptide Y in the arcuate nucleus of the hypothalamus and in nucleus tractus solitaries was examined. Triglycerides and leptin levels were increased in the high-fat diet mother. The number of neuropeptide Y positive cell bodies and neurons was significantly increased in the high-fat diet-F1 offspring (HDF-F1) as compared to Chow-F1. Leptin administration significantly decreased the food intake and increased the pSTAT3 expression levels in neurons in the arcuate nucleus of Chow-F1. However, leptin did not show any effect on food intake and had a reduced effect on pSTAT3 expression levels in neurons in the arcuate nucleus of HDF-F1. From the present domino effect, we conclude that mothers exposed to high-fat diet during pregnancy may pass the obese phenotype to the succeeding generation via altering hypothalamic leptin signaling.

8.
Artículo en Inglés | MEDLINE | ID: mdl-12215796

RESUMEN

H7C is a HBV integrated fragment isolated from a human hepatocellular carcinoma, containing the promoter of preS2 and the C-terminal truncated preS/S open reading frame. We have studied the effect of the 3'-truncated preS/S on human proliferating cell nuclear antigen (PCNA) promoter by co-transfection of the expression plasmids. Result showed that the product, pKSH7C-Hpa I, which contained the intact H7C and the flanking cellular sequences, stimulated the expression from PCNA promoter dose-dependently, and its effect was 1-2 folds higher than that on SV40 promoter. However, two subclones, pKSH7C-XHX and pKSH7C-XbH, which would not express preS/S, showed no stimulatory effect. Furthermore, when if the -45 bp ATF-like site was mutated, the activation effect became diminished. This showed that the ATF-like site might be important in mediating the transactivating process. This is the first report of the effect of a HBV integrated fragment on the promoter of a replicating protein factor.

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