The relationship between duration of infertility and clinical outcomes of intrauterine insemination for younger women: a retrospective clinical study.

BACKGROUND: The objective of this research was to elucidate the association between the length of infertility and the outcomes of intrauterine insemination (IUI) in women of varying ages - a topic that has been the subject of investigation for numerous years, yet lacks a definitive consensus. METHODS: A retrospective cohort investigation involving 5268 IUI cycles was undertaken at the Reproductive Medicine Center of Nanjing Drum Tower Hospital from 2016 to 2022. Utilizing the smooth fitting curve along with threshold and saturation effect analysis, the correlation between infertility duration and IUI clinical pregnancy rates was discerned. Moreover, patients were bifurcated into two cohorts based on their respective infertility durations. A secondary examination was also performed employing propensity-score matching to mitigate the impact of confounding variables. Subsequent threshold and saturation effect analysis was carried out across various subgroups, segmented on the basis of age differentiation. RESULTS: When the duration of infertility was more than 5 years, the clinical pregnancy rate decreased with the increase of infertility duration (aOR: 0.894, 95%CI: 0.817-0.991, p = 0.043). The multivariate regression analysis suggested that longer duration of infertility (≥ 5 years) was significantly correlated with the lower clinical pregnancy rate (aOR: 0.782, 95% CI: 0.643-0.950, p = 0.01). After the propensity-score matching, the clinical pregnancy rate of women with longer infertility duration were also higher. When the duration of infertility was more than 5 years, the clinical pregnancy rate of women younger than 35 years old decreased with the increase of infertility duration (aOR: 0.906, 95%CI: 0.800-0.998, p = 0.043). CONCLUSIONS: The clinical pregnancy rate and live birth rate of IUI in young women (< 35 years old) who have been infertile for more than 5 years significantly decrease with the prolongation of infertility time. Therefore, for young women who have been infertile for more than 5 years, IUI may not be the best choice.

Perinatal outcomes of singletons following double vitrification-warming procedures: a retrospective study using propensity score analysis.

BACKGROUND: Although repeated cryopreservation is an occasional occurrence, the effect on perinatal outcomes is unclear. Therefore, the aim of this study was to evaluate the perinatal outcomes of singletons after embryo re-cryopreservation. METHODS: In this retrospective study, a total of 647 singleton live births after blastocyst freeze-thaw embryo transfer cycles were investigated. They were divided into two groups: vitrified-warmed blastocysts (once-vitrified group) and vitrified-warmed blastocysts derived from thawed cleaved embryos (re-vitrified group). Propensity score matching (PSM) was used to control for potential confounding factors. RESULTS: A total of 592 infants were included in the once-vitrified group, and 55 infants were included in the re-vitrified group. After PSM, 108 cases were generated for comparison. The median gestational age was 38 weeks for both groups, and the birthweights were comparable (3390.6 ± 601.5 g vs. 3412.8 ± 672.6 g, P > 0.05). The incidence of preterm birth (PTB) (20.4% vs. 16.7%), low birthweight (LBW) (3.7% vs. 7.4%), macrosomia (11.1% vs. 16.7%) and large for gestational age (LGA) (29.6% vs. 22.2%) were not significantly different between the two groups. Logistic regression analysis indicated that double vitrification-warming procedures did not affect the occurrence of PTB (OR, 2.58 [95% CI, 0.77, 8.63]), LBW (OR, 0.83 [95% CI, 0.08, 8.29]), macrosomia (OR, 0.60 [95% CI, 0.13, 2.69]), or LGA (OR, 1.51 [95% CI, 0.53, 4.27]) (P > 0.05, for all). CONCLUSION: Our findings demonstrate that double vitrification-warming procedures do not increase the risk of adverse neonatal outcomes compared with those of once-vitrified embryos.

Nanoconfined Electrochemical Collision and Catalysis of Single Enzyme inside Carbon Nanopipettes.

Revealing the electrocatalytic features of single redox enzyme is significant to both fundamental biological processes and practical catalysis and sensing applications. Herein, we directly reveal the electrocatalytic current from a single enzyme inside the carbon nanopipettes via electrochemical collision strategies, based on the increased activity at nanoscale confinement. Besides the staircase current steps from surface blockage, discrete H2O2 oxidation and reduction current transients catalyzed by a single enzyme are also displayed and analyzed. The carbon nanopipette would increase the catalytic activities of enzymes and lead to a detectable current response, thus opening a new way to investigate the fundamental enzymatic mechanisms at the single enzyme level.

Electrodeposition of Metal Nanoparticles inside Carbon Nanopipettes for Sensing Applications.

Conductive nanopipettes offer promising confined spaces to enable advanced electrochemical sensing applications in small spaces. Herein, a series of metal-decorated carbon nanopipettes (CNPs) were developed, in which Au, Ag, and Pt are modified at the inner walls of CNPs by a simple electrodeposition method. The fabricated tips show good sensing performances for a variety of important analytes, such as glucose, hydrogen peroxide, and chloride and hydrogen ions in biological and catalytic systems. This simple and effective approach can be further extended to prepare other functionalized nanopipette electrodes toward more versatile and powerful measurements in electrochemical sensing and imaging applications.

Effect of recombinant LH supplementation timing on clinical pregnancy outcome in long-acting GnRHa downregulated cycles.

BACKGROUND: Timely and moderate luteinizing hormone (LH) supplementation plays positive roles in in vitro fertilization/intracytoplasmic sperm injection and embryo transfer (IVF/ICSI-ET) cycles with long-acting gonadotropin-releasing hormone agonist (GnRHa) pituitary downregulation. However, the appropriate timing of LH supplementation remains unclear. METHODS: We carried out a retrospective cohort study of 2226 cycles at our reproductive medicine centre from 2018 to 2020. We mainly conducted smooth curve fitting to analyse the relationship between the dominant follicle diameter when recombinant LH (rLH) was added and the clinical pregnancy outcomes (clinical pregnancy rate or early miscarriage rate). In addition, total cycles were divided into groups according to different LH levels after GnRHa and dominant follicle diameters for further analysis. RESULTS: Smooth curve fitting showed that with the increase in the dominant follicle diameter when rLH was added, the clinical pregnancy rate gradually increased, and the early miscarriage rate gradually decreased. CONCLUSIONS: In long-acting GnRHa downregulated IVF/ICSI-ET cycles, the appropriate timing of rLH supplementation has a beneficial impact on the clinical pregnancy outcome. Delaying rLH addition is conducive to the clinical pregnancy rate and reduces the risk of early miscarriage.

Electrochemical Collision of Single Silver Nanoparticles in Carbon Nanopipettes.

Exploring the electrochemical collision features at nanoelectrodes is highly desirable for revealing new physical insights and further expanding its applications at smaller spaces. Herein, we study the collision processes of single silver nanoparticles (AgNPs) inside carbon nanopipettes (CNPs). Results show that AgNPs undergo multiple collision and oxidation processes prior to fully oxidation after entering into the CNPs. Different from the disk electrodes, the produced Ag+ cannot immediately diffuse away from the cavity and will be reduced once switching to reductive potentials. More intriguingly, we observe discrete cathodic spikes from the Ag+ reduction, which are presumably due to the negatively charged carbon surface confined in the CNPs. The elucidated collision features in a CNP would enable its better usage for single entity measurements at confined spaces.

Altered viral replication and cell responses by inserting microRNA recognition element into PB1 in pandemic influenza A virus (H1N1) 2009.

Objective. MicroRNAs (miRNAs) are endogenous noncoding RNAs that spatiotemporally modulate mRNAs in a posttranscriptional manner. Engineering mutant viruses by inserting cell-specific miRNA recognition element (MRE) into viral genome may alter viral infectivity and host responses in vital tissues and organs infected with pandemic influenza A virus (H1N1) 2009 (H1N1pdm). Methods. In this study, we employed reverse genetics approach to generate a recombinant H1N1pdm with a cell-specific miRNA target sequence inserted into its PB1 genomic segment to investigate whether miRNAs are able to suppress H1N1pdm replication. We inserted an MRE of microRNA-let-7b (miR-let-7b) into the open reading frame of PB1 to test the feasibility of creating a cell-restricted H1N1pdm virus since let-7b is abundant in human bronchial epithelial cells. Results. miR-let-7b is rich in human bronchial epithelial cells (HBE). Incorporation of the miR-let-7b-MRE confers upon the recombinant H1N1pdm virus susceptibility to miR-let-7b targeting, suggesting that the H1N1pdm and influenza A viruses can be engineered to exert the desired replication restrictive effect and decrease infectivity in vital tissues and organs. Conclusions. This approach provides an additional layer of biosafety and thus has great potential for the application in the rational development of safer and more effective influenza viral vaccines.

Automatic sleep-wake classification and Parkinson's disease recognition using multifeature fusion with support vector machine.

AIMS: Sleep disturbance is a prevalent nonmotor symptom of Parkinson's disease (PD), however, assessing sleep conditions is always time-consuming and labor-intensive. In this study, we performed an automatic sleep-wake state classification and early diagnosis of PD by analyzing the electrocorticography (ECoG) and electromyogram (EMG) signals of both normal and PD rats. METHODS: The study utilized ECoG power, EMG amplitude, and corticomuscular coherence values extracted from normal and PD rats to construct sleep-wake scoring models based on the support vector machine algorithm. Subsequently, we incorporated feature values that could act as diagnostic markers for PD and then retrained the models, which could encompass the identification of vigilance states and the diagnosis of PD. RESULTS: Features extracted from occipital ECoG signals were more suitable for constructing sleep-wake scoring models than those from frontal ECoG (average Cohen's kappa: 0.73 vs. 0.71). Additionally, after retraining, the new models demonstrated increased sensitivity to PD and accurately determined the sleep-wake states of rats (average Cohen's kappa: 0.79). CONCLUSION: This study accomplished the precise detection of substantia nigra lesions and the monitoring of sleep-wake states. The integration of circadian rhythm monitoring and disease state assessment has the potential to improve the efficacy of therapeutic strategies considerably.

ZP1-Y262C mutation causes abnormal zona pellucida formation and female infertility in humans.

Defective oocyte maturation is a common cause of female infertility. The loss of the zona pellucida (ZP) represents a specific condition of impaired oocyte maturation. The extracellular matrix known as the ZP envelops mammalian oocytes and preimplantation embryos, exerting significant influence on oogenesis, fertilization, and embryo implantation. However, the genetic factors leading to the loss of the ZP in oocytes are not well understood. This study focused on patients who underwent oocyte retrieval surgery after ovarian stimulation and were found to have abnormal oocyte maturation without the presence of the ZP. Ultrasonography was performed during the surgical procedure to evaluate follicle development. Peripheral blood samples from the patient were subjected to exome sequencing. Here, a novel, previously unreported heterozygous mutation in the ZP1 gene was identified. Within the ZP1 gene, we discovered a novel heterozygous mutation (ZP1 NM_207341.4:c.785A>G (p.Y262C)), specifically located in the trefoil domain. Bioinformatics comparisons further revealed conservation of the ZP1-Y262C mutation across different species. Model predictions of amino acid mutations on protein structure and cell immunofluorescence/western blot experiments collectively confirmed the detrimental effects of the ZP1-Y262C mutation on the function and expression of the ZP1 protein. The ZP1-Y262C mutation represents the novel mutation in the trefoil domain of the ZP1 protein, which is associated with defective oocyte maturation in humans. Our report enhances comprehension regarding the involvement of ZP-associated genes in female infertility and offers enriched understanding for the genetic diagnosis of this condition.

Krüppel-like factor 12 negatively regulates human endometrial stromal cell decidualization.

Members of the KLFs family of transcription factors play roles in maternal endometrium development during embryo implantation. However, the specific role of KLF12 in endometrium development has not yet been described. In this study, we showed that KLF12 expression in human endometrial stromal cells (HESCs) was significantly decreased after decidualization stimulated by 8-Br-cAMP and medroxyprogesterone acetate (MPA). The adenovirus-mediated overexpression of KLF12 in HESCs significantly repressed the expression and secretion of decidualization biomarker genes and their products decidual prolactin (PRL) and insulin-like growth factor binding protein-1 (IGFBP-1) induced by 8-Br-cAMP and MPA. Moreover, CHIP and luciferase reporter assays demonstrated that KLF12 bound to a CAGTGGG element within the decidual prolactin promoter and decreased decidual PRL promoter (dPRL/-2000Luc) activation in a sequence-specific manner. Taken together, these findings suggest KLF12 is a negative regulator of human endometrial stromal cell decidualization.

CAPN 7 promotes the migration and invasion of human endometrial stromal cell by regulating matrix metalloproteinase 2 activity.

BACKGROUND: Matrix metalloproteinase 2 (MMP-2) has been reported to be an important regulator of cell migration and invasion through degradation of the extracellular matrix (ECM) in many diseases, such as cancer and endometriosis. Here, we found calcium-activated neutral protease 7 (CAPN 7) expression was markedly upregulated in the eutopic endometrium and endometrial stromal cells of women diagnosed with endometriosis. Our studies were carried out to detect the effects of CAPN 7 on human endometrial stromal cell (hESC) migration and invasion. METHODS: Western blotting and quantitative real-time PCR were used to detect the expression of CAPN 7 in endometriosis patients and normal fertile women. Scratch-wound-healing and invasion chamber assay were used to investigate the role of CAPN 7 in hESC migration and invasion. Western blotting, quantitative real-time PCR and zymography were carried out to detect the effect of CAPN 7 on the expressions and activity of MMP-2. RESULTS: CAPN 7 was markedly up-regulated in endometriosis, thereby promoting the migration and invasion of hESC. CAPN 7 overexpression led to increased expression of MMP-2 and tissue inhibitor of metalloproteinases 2 (TIMP-2); CAPN 7 knockdown reversed these changes. CAPN 7 increased MMP-2 activity by increasing the ratio of MMP-2 to TIMP-2. We also found that OA-Hy (an MMP-2 inhibitor) decreased the effects of CAPN 7 overexpression on hESC migration and invasion by approximately 50% and 55%, respectively. Additionally, a coimmunoprecipitation assay demonstrated that CAPN 7 interacted with activator protein 2α (AP-2α): an important transcription factor of MMP-2. CONCLUSIONS: CAPN 7 promotes hESC migration and invasion by increasing the activity of MMP-2 via an increased ratio of MMP-2 to TIMP-2.

Withdrawal of GnRH agonist decreases oestradiol and VEGF concentrations in high responders.

This study evaluated whether the withdrawal of a gonadotrophin-releasing hormone (GnRH) agonist before triggering ovulation reduces the incidence of ovarian hyperstimulation syndrome (OHSS) in high-risk infertility patients who were treated with gonadotrophins. GnRH agonist was withdrawn for 2 or 3 days when dominant follicles were ≥14 mm in diameter, according to the GnRH agonist long protocol. Non-withdrawal of GnRH agonist was used as control. The serum concentration of oestradiol on the ovulation trigger day was significantly decreased in the GnRH agonist withdrawal group compared with the control group (5750.78 ± 2344.77 pg/ml versus 8076.43 ± 1981.67 pg/ml); however, the number of retrieved oocytes and the fertilization rate were similar between the groups. In addition, the concentrations of vascular endothelial growth factor in plasma on day of human chorionic gonadotrophin administration and follicular fluid on the oocyte retrieval day were decreased following GnRH agonist withdrawal. In fresh embryo transfer cycles, rates of clinical pregnancy, implantation and OHSS were not different between the groups. When GnRH agonist withdrawal was followed by total embryos cryopreserved, the rate of OHSS was decreased compared with the control group (0% versus 8.70%). Clinical pregnancy rates in cryopreserved embryo transfer cycles were comparable between the two groups.

Molecular Electrocatalytic Processes in Carbon Nanopipettes.

Conductive nanopipettes have been recognized as powerful multifunctional platforms for electrochemical sensing applications in confined spaces. However, the electron-transfer processes of many biological analytes (i.e., enzymes or proteins) are slow and coupled with chemical reactions, which have not been well elucidated in conductive nanopipettes. In this Letter, both experimental and simulation methods are used to study electron-transfer processes coupled to chemical reactions (EC mechanism) in carbon nanopipettes (CNPs). It is demonstrated that the electroactive species can serve as redox mediator to help oxidize and reduce the nonelectroactive analytes of interest in the solution and produce noticeable catalytic current signals. Besides, glutathione was directly measured by using ferrocenemethanol as the redox mediator in the CNPs. The elucidated EC processes in CNPs would offer a new opportunity to measure nonelectroactive analytes in biological fields.

Case report: A novel homozygous variant in ZP3 is associated with human empty follicle syndrome.

Empty follicle syndrome (EFS) is a rare condition in female infertility. It is characterized by the inability to retrieve oocytes from visibly large, normally developing follicles in the ovaries, despite ovarian stimulation. The genetic factors contributing to this syndrome remain unclear. This study focused on patients who underwent three consecutive ovarian stimulation procedures for oocyte retrieval but experienced unsuccessful outcomes, despite the presence of observable large follicles. Ultrasound examinations were conducted to assess follicular development during each procedure. In order to investigate potential genetic causes, we performed whole exome sequencing on peripheral blood samples from the patient. Interestingly, we identified that this patient carries a homozygous mutation in the ZP3 genes. Within the ZP3 gene, we identified a homozygous variant [NM_001110354.2, c.176T>A (p.L59H)] specifically located in the zona pellucida (ZP) domain. Further analysis, including bioinformatics methods and protein structure modeling, was carried out to investigate the conservation of the ZP3L59H variant across different species. This homozygous variant exhibited a high degree of conservation across various species. Importantly, the homozygous ZP3L59H variant was associated with the occurrence of empty follicle syndrome in affected female patients. The homozygous ZP3L59H variant represents a newly discovered genetic locus implicated in the development of human empty follicle syndrome. Our findings contribute to a deeper understanding of the role of zona pellucida-related genes in infertility and provide valuable insights for the genetic diagnosis of female infertility.

The relationship between dominant follicle development and clinical outcomes of hormone replacement therapy-frozen embryo transfer: a retrospective clinical study.

Research question: Hormone replacement therapy (HRT) is one of the most used endometrial preparation protocols for frozen embryo transfer (FET) due to the convenience of its administration and stability of pregnancy outcomes. There are several HRT cycles accompanied by the development of dominant follicles. However, the relationship between dominant follicle development and clinical outcomes in HRT-FET cycles remains unclear. Design: We carried out a retrospective cohort study of 13251 cycles at our reproductive medicine center from 2012 to 2019. Total cycles were divided into two groups according to whether there was dominant follicular development. In addition, we conducted a secondary analysis that used propensity-score matching to reduce confounding variables. A univariate and multivariable logistic regression model was further employed to analyze the effect of dominant follicle development in HRT cycles on clinical pregnancy outcomes. Results: There was no significant correlation between dominant follicle development in HRT-FET cycles and the clinical pregnancy rate (adjusted OR = 1.162, 95% CI: 0.737-1.832, P = 0.52). In addition, there was a positive correlation between the basic follicle-stimulating hormone (FSH) level and the development of dominant follicles, while there was a negative correlation between antral follicle count (AFC), menstrual cycle length and the development of dominant follicles in HRT cycles. Conclusions: The development of dominant follicles in HRT-FET cycles does not affect the clinical pregnancy rate, early miscarriage rate and live birth rate. Therefore, it is not necessary to immediately cancel the FET cycle immediately when dominant follicle development is monitored in the HRT-FET cycle.

A novel homozygous variant in PADI6 is associate with human cleavage-stage embryonic arrest.

Repeated absence of useable embryos is a difficult problem for infertility patients. Among them, embryonic developmental arrest is more common, but the genetic cause is not known. The embryos of a patient who came to our hospital three times could not develop beyond the four-cell stage. In addition to recording the developmental details of the embryos by daily photo-taking, the PADI6 R132C homozygous variants was further confirmed by whole-exome sequencing. Subsequently, PADI6 R132C was analyzed by bioinformatics methods for conservativeness across species. In addition, the possible impact of the pathogenic mutation on the structure of the protein PADI6 were also assessed. Generally, we identified a homozygous variants [NM_207421.4, c.394C>T(p.R132C] in the middle protein-arginine deiminase domain in PADI6 gene. The homozygous variant is highly conserved across species. Homozygous variant in PADI6 R132C could cause a human cleavage-stage embryonic arrest in female patients. These findings provide further evidence for the important roles of the homozygous PADI6R132C variant in embryonic development. Our findings contribute to a deeper understanding of the molecular genetic basis of female infertility.

Effect of Elevated Progesterone Levels on hCG Trigger Day on Clinical Pregnancy Outcome in Short-Acting GnRHa Downregulated Cycles.

Background: Previous studies suggested higher serum progesterone (P) levels were strongly associated with a lower clinical pregnancy rate (CPR) for in vitro fertilization-embryo transfer (IVF-ET). However, the effect of increased serum P levels on the day of human chorionic gonadotropin (hCG) administration on clinical outcomes in short-acting gonadotropin-releasing hormone agonist (GnRHa) downregulated IVF-ET cycles remains unclear. Methods: We conducted a retrospective cohort study from January 2017 to December 2021, which included a total of 1664 patients receiving their first short-acting GnRHa IVF-ET cycles at our reproductive medicine centre of Nanjing Drum Tower Hospital. The smooth curve fitting and interaction analysis were employed to analyse the association between the CPR and the serum P levels with different embryo types (cleavage-stage embryo or blastocyst). In addition, total cycles were grouped according to different P levels on the trigger day of hCG administration for further analysis. Results: The CPR of patients with increased serum P level (higher than 1.5 ng/mL) on the hCG day did not decrease. A smoothing curve fitting showed that the CPR did not change obviously with the increase in serum P levels. Subgroup analysis of different types of embryos transferred showed that no correlation was observed between the CPR and serum P levels on the day of hCG administration in cleavage-stage embryo transfer cycles. However, the CPR of patients receiving blastocyst transfer showed a downward trend with the increase in serum P levels. At the same time, an interaction analysis also confirmed that the CPR of blastocyst transfer was more likely to be affected by elevated serum P levels on the hCG day. Conclusion: In the luteal phase short-acting GnRHa downregulated IVF-ET cycles, the elevated serum P levels on the hCG day did not affect the CPR of cleavage-stage embryo transfer but reduced the CPR of blastocyst transfer.

Hormone replacement therapy alone or in combination with tamoxifen in women with thin endometrium undergoing frozen-thawed embryo transfer: A retrospective study.

Research question: To investigate the effects of two protocols (hormone replacement therapy (HRT) alone or in combination with tamoxifen) on the endometrium and pregnancy outcome of patients with thin endometrium in frozen-thawed embryo transfer (FET) cycles. Design: A total of 465 infertile patients with thin endometrium who underwent FET between January 2020 to June 2021 at the Drum Tower Hospital affiliated with Nanjing University Medical School were retrospectively analyzed. A total of 187 patients were given tamoxifen in addition to HRT (TMXF-HRT group), whereas 278 patients were given only HRT (HRT group). Clinical data were compared between the two groups, including general characteristics, endometrial thickness, and clinical pregnancy outcomes. Results: There were no significant differences in baseline characteristics of all enrolled patients between two groups. Serum progesterone (P) was higher in HRT group than in the TMXF-HRT group (0.28 ± 0.53 ng/mL vs. 0.15 ± 0.25 ng/mL, P = 0.002). There was a significant increase in endometrial thickness in the TMXF-HRT group compared with the HRT group (OR: 1.54, 95% CI: 1.32-1.75, P < 0.001). There were no significant differences in the clinical pregnancy rate, embryo implantation rate, early miscarriage rate, or live birth rate between these two groups. Conclusion: Although tamoxifen when used in combination with hormone replacement therapy can significantly increase endometrial thickness, it may not have a role in improving the pregnancy outcomes of patients with thin endometrium undergoing FET cycles.

Multivalent Ion-Modulated Electron Transfer Processes in Carbon Nanopipettes.

Conductive nanopipettes with both an electroactive interface and a pipet geometry have been recognized as powerful multifunctional probes in various electrochemical sensing and imaging applications. As confined inside the nanopipette, the excess surface charges at the solid/solution interface would then play a dominant role in the resulting charge transport processes. Herein, the effects of a multivalent ion on the resulting electron transfer (ET) processes in the carbon nanopipettes are investigated with both experimental and simulation methods. The multivalent cations (i.e., Ca2+, Mg2+, Co2+, and Ni2+) are shown to strongly adsorb at the negatively charged carbon surface and attract more Fe(CN)64- ions inside the cavity, as indicated by the increasing ET current responses. In addition to elucidating the fundamental charge transport processes in conductive nanopipettes to afford better usage as electrochemical probes, these results could also help in the development of new sensing methods for measuring the non-electroactive ions in biological or environmental systems.