Global Navigation Satellite System Receiver Positioning in Harsh Environments via Clock Bias Prediction by Empirical Mode Decomposition and Back Propagation Neural Network Method.

This paper proposes a novel method to improve the clock bias short-term prediction accuracy of navigation receivers then solve the problem of low positioning accuracy when the satellite signal quality deteriorates. Considering that the clock bias of a navigation receiver is equivalent to a virtual satellite, the predicted value of clock bias is used to assist navigation receivers in positioning. Consequently, a combined prediction method for navigation receiver clock bias based on Empirical Mode Decomposition (EMD) and Back Propagation Neural Network (BPNN) analysis theory is demonstrated. In view of systematic errors and random errors in the clock bias data from navigation receivers, the EMD method is used to decompose the clock bias data; then, the BPNN prediction method is used to establish a high-precision clock bias prediction model; finally, based on the clock bias prediction value, the three-dimensional positioning of the navigation receiver is realized by expanding the observation equation. The experimental results show that the proposed model is suitable for clock bias time series prediction and providing three-dimensional positioning information meets the requirements of navigation application in the harsh environment of only three satellites.

Integration of hepatitis B virus into patients' sperm genome and its clinical risks.

BACKGROUND: Like the coronavirus disease 2019, the hepatitis B virus is also wreaking havoc worldwide, which has infected over 2 billion people globally. Using an experimental animal model, our previous research observed that the hepatitis B virus genes integrated into human spermatozoa can replicate and express after being transmitted to embryos. However, as of now, this phenomenon has not been confirmed in clinical data from patients. OBJECTIVES: To explore the integration of the hepatitis B virus into patients' sperm genome and its potential clinical risks. MATERIALS AND METHODS: Forty-eight patients with chronic hepatitis B virus infection were categorized into two groups: Test Group-1 comprised 23 patients without integration of hepatitis B virus DNA within the sperm genome. Test Group-2 comprised 25 patients with integration of hepatitis B virus DNA within the sperm genome. Forty-eight healthy male donors were included as control. The standard semen parameter analysis, real-time polymerase chain reaction, quantitative real-time polymerase chain reaction, sperm chromatin structure assay, fluorescence in situ hybridization, and immunofluorescence assays were utilized. RESULTS: The difference in the median copy number of hepatitis B virus DNA per mL of sera between Test Group-1 and Group-2 was not statistically significant. In Test Group-2, the integration rate of hepatitis B virus DNA was 0.109%, which showed a significant correlation with the median copy number of hepatitis B virus DNA in motile spermatozoa (1.18 × 103 /mL). Abnormal semen parameters were found in almost all these 25 patients. The integrated hepatitis B virus S, C, X, and P genes were detected to be introduced into sperm-derived embryos through fertilization and retained their function in replication, transcription, and translation. CONCLUSION: Our findings suggest that hepatitis B virus infection can lead to sperm quality deterioration and reduced fertilization capacity. Furthermore, viral integration causes instability in the sperm genome, increasing the potential risk of termination, miscarriage, and stillbirth. This study identified an unconventional mode of hepatitis B virus transmission through genes rather than virions. The presence of viral sequences in the embryonic genome poses a risk of liver inflammation and cancer.

Low SNR multimirror Fabry-Perot pressure sensor optic spectrum signal analysis and demodulation via SVM-KNN regressors.

We demonstrate an ensemble learning based method to solve the problem of low SNR Fabry-Perot sensor spectrum signal demodulation. Taking the eight-layer approximate coefficients of a multilevel discrete wavelet transform as input features, an ensemble model that combines multiple SVM and KNN learners is trained. Bootstrap and booting techniques are introduced for better modeling performance and stability. It is shown that the performance of the proposed ensemble model based on SVM-KNN regressors is excellent; an accuracy of 0.46%F.S. relative mean error is achieved. This method could provide insight into the construction of a large scale fiber based Fabry-Perot sensor network.

Age at menarche and risk of ovarian hyperstimulation syndrome in women undergoing IVF/ICSI cycles: a retrospective cohort study.

OBJECTIVES: We aimed to explore the association between age at menarche (AAM) and ovarian hyperstimulation syndrome (OHSS) in fresh in vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) cycles. DESIGN: A retrospective cohort study. SETTING: Data were collected from a large obstetrics and gynaecology hospital in Sichuan, China. PARTICIPANTS: This study included 17 419 eligible women aged ≤40 years who underwent the first IVF/ICSI cycles from January 2015 to December 2021. Women were divided into three groups according to their AAM: ≤12 years (n=5781), 13-14 years (n=9469) and ≥15 years (n=2169). RESULTS: The means of age at recruitment and AAM were 30.4 years and 13.1 years, respectively. Restricted cubic spline models suggested that early menarche age increased the risk of OHSS. The multivariable logistic analysis showed that women with menarche age ≤12 years were more likely to suffer from OHSS (OR 1.321, 95% CI 1.113 to 1.567) compared with those aged 13-14 years among the whole cohort. This significant relationship remained in women administered with different ovarian stimulation protocols and gonadotrophin doses. When stratified by female age, this correlation was presented only in patients aged ≤30 years (OR 1.362, 95% CI 1.094 to 1.694). And the mediation analysis showed that the relationship between AAM and OHSS was totally mediated by antral follicle counts (AFC). CONCLUSION: Menarche age earlier than 12 years may increase the OHSS risk in women aged ≤30 years through the mediation of AFC. More prospective studies are required to verify the results.

The influence of male HBV infection on sperm quality, embryonic development, and assisted reproductive outcomes.

STUDY QUESTION: What is the impact of male hepatitis B virus (HBV) infection on sperm quality, embryonic development, and assisted reproductive outcomes? SUMMARY ANSWER: Male HBV infection did not affect assisted reproductive outcomes, but HBV is capable of impairing human sperm and embryo formation in the early stages following fertilization. WHAT IS KNOWN ALREADY: HBV is found in germ cells and early embryos of patients with HBV. HBV may impair human sperm function via increasing reactive oxygen species. STUDY DESIGN, SIZE, DURATION: We conducted a retrospective cohort study of 1581 infertile couples, including 496 male patients clinically confirmed to have hepatitis B infection, and a laboratory study of effects of HBV proteins on early embryos, using human embryonic stem cells (hESCs), human sperm, and golden hamster oocytes. PARTICIPANTS/MATERIALS, SETTING, METHODS: In total, 1581 infertile couples (24-40 years of age) who were admitted to a reproductive medicine center to undergo ART for the first time from January 2019 to November 2021 were selected as the study subjects. The case group was composed of 469 couples with hepatitis B surface antigen (HBsAg)-seropositive men and seronegative women (368 for IVF and 101 for ICSI treatment). The negative control group was composed of 1112 couples where both men and women were seronegative for hepatitis B antigen. We divided these couples into three comparison groups (IVF/ICSI, IVF, and ICSI). IVF of human sperm and hamster oocytes was used to evaluate the influence of the HBV HBs protein on formation of 2-cell embryos. Mitochondrial membrane potential (MMP) of hESCs was assayed via a fluorescence intensity system. Immunofluorescence staining of the phosphorylated histone H2A.X was applied to identify DNA damage to hESCs caused by the HBV X (HBx) protein. MAIN RESULTS AND THE ROLE OF CHANCE: Sperm concentration, total sperm number, and sperm with normal morphology were decreased in the couples with HBV-infected males in couples who were undergoing IVF/ICSI (male HBV(+) vs control: 469 vs 1112 individuals; sperm number, P < 0.01; normal sperm morphology, P < 0.01), IVF (368 vs 792; sperm number, P < 0.01; normal sperm morphology, P ≤ 0.05), and ICSI (101 vs 306; sperm number, P < 0.01; normal sperm morphology, P < 0.001). There was no significant difference in the number of embryo cleavages, blastocyst formation, biochemical pregnancy rate, clinical pregnancy rate, and live-birth rate between case and control groups. The 2PN fertilization rate in IVF/ICSI (P < 0.01) and ICSI (P < 0.05) couples, and the number of 2PN-fertilized oocytes in IVF (P < 0.001) couples were lower in couples with male HBV infection compared to control couples. HBV HBs protein reduced the MMP of human sperm and decreased 2-cell embryo formation in IVF of human sperm and zona-free-hamster oocyte. A reduction in fluorescence intensity and immunofluorescence staining of phosphorylated histone H2A.X indicated that HBx caused MMP impairment and DNA damage in human early embryonic cells, respectively. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: HBV can be examined in samples of sperm or discarded IVF early embryos from HBsAg-seropositive men and seronegative women. The hESC model in vitro may not fully mimic the natural embryos in vivo. WIDER IMPLICATIONS OF THE FINDINGS: This study furthers our understanding of the influence of male HBV infection on embryonic development. Our results suggest that a semen-washing process may be necessary for male patients with HBV undergoing ART to minimize the potential negative effects of HBV infection on the early embryo. STUDY FUNDING/COMPETING INTEREST(S): This work was funded by grants from the National Natural Science Foundation of China, grant numbers 81870432 and 81570567 to X.Z., 81571994 to P.S., and 81950410640, the Natural Science Foundation of Guangdong Province, China (No. 2023A1515010660 to X.Z.), and the Li Ka Shing Shantou University Foundation (Grant No. L11112008). The authors have no conflicts of interest.

Young obese patients may benefit from GnRH-a long protocol contributing to higher implantation rate and live birth rate of fresh IVF-ET cycles.

Introduction: Obesity has detrimental influences on women reproductive health. There is little experience in optimizing controlled ovarian hyperstimulation (COH) protocols to treat Chinese obese patients who are undergoing in vitro fertilization and embryo transfer (IVF-ET) therapy. Methods: The clinical outcome differences were retrospectively analyzed among obese patients who received gonadotrophin-releasing hormone agonist (GnRH-a), GnRH antagonist (GnRH-ant), micro dose GnRH-a (mGnRH-a) and GnRH-a long protocol in IVF-ET cycle at Chengdu Jinjiang Hospital for Women's and Children's Health from January 2014 to December 2019. Results: The transplantation rate of the GnRH-a long protocol group (59.1%) was higher than that of the GnRH-ant (25.9%) and mGnRH-a (36.7%) groups. The total live birth rate of the GnRH-a long protocol group (46.2%) was higher than that of the GnRH-a group (25.9%) and GnRH-ant group (40.3%). The total number of frozen embryos in the GnRH-ant group was higher than in the other groups (P < 0.05). After adjusting for confounding factors, the logistic regression analysis showed that the GnRH-a long protocol group had higher probabilities of biochemical pregnancy, clinical pregnancy, and live birth than the GnRH-a protocol group. The Gn dose in the mGnRH-a group was higher than the other three groups. Whether single or twin, there were similar neonatal outcomes among the four groups including premature birth rate, Apgar score, newborn weight, and length. Conclusion: For young obese patients undergoing IVF-ET, the GnRH-a long protocol for COH gives better pregnancy outcomes.

Analysis of scanning systematic errors for airborne laser bathymetry.

For the Palmer mechanical scanning pattern of an airborne laser bathymetry system, the potential errors of the scanning system are analyzed, and the associated error model is derived. The model composes the description of laser rays, water surface fluctuations, and refraction, and introduces certain simplifications concerning the water surface and column. Based on the scanning error model, the impact of each error source on the vertical and horizontal positioning accuracy is investigated and established through a numerical simulation. The quantitative impacts of each inaccuracy on the coordinates of the laser footprints on the sea surface and bottom were calculated, with a height of 100 m for the airborne platform and a water depth of 10 m. To verify the correctness of the simulation results and the error model based on a theoretical analysis, experiments are utilized with the system that we developed. Both the simulation analysis and experimental results show that this method can effectively obtain the systematic errors. The outcomes of the error model and analysis will give the theoretical foundations for lowering the effect brought on by each error source in the compensation scanning system and improving the point cloud accuracy in the ensuing data processing.

Influence of Vitamin D supplementation on reproductive outcomes of infertile patients: a systematic review and meta-analysis.

BACKGROUND: Low vitamin D status has been associated with an increased risk for infertility. Recent evidence regarding the efficacy of vitamin D supplementation in improving reproductive outcomes is inconsistent. Therefore, this systematic review was conducted to investigate whether vitamin D supplementation could improve the reproductive outcomes of infertile patients and evaluate how the parameters of vitamin D supplementation affected the clinical pregnancy rate. METHODS: We searched seven electronic databases (CNKI, Cqvip, Wanfang, PubMed, Medline, Embase, and Cochrane Library) up to March 2022. Randomized and cohort studies were collected to assess the reproductive outcomes difference between the intervention (vitamin D) vs. the control (placebo or none). Mantel-Haenszel random effects models were used. Effects were reported as odds ratio (OR) and their 95% confidence interval (CI). PROSPERO database registration number: CRD42022304018. RESULTS: Twelve eligible studies (n = 2352) were included: 9 randomized controlled trials (RCTs, n = 1677) and 3 cohort studies (n = 675). Pooled results indicated that infertile women treated with vitamin D had a significantly increased clinical pregnancy rate compared with the control group (OR: 1.70, 95% CI: 1.24-2.34; I2 = 63%, P = 0.001). However, the implantation, biochemical pregnancy, miscarriage, and multiple pregnancy rates had no significant difference (OR: 1.86, 95% CI: 1.00-3.47; I2 = 85%, P = 0.05; OR: 1.49; 0.98-2.26; I2 = 63%, P = 0.06; OR: 0.98, 95% CI: 0.63-1.53; I2 = 0%, P = 0.94 and OR: 3.64, 95% CI: 0.58-11.98; I2 = 68%, P = 0.21). The improvement of clinical pregnancy rate in the intervention group was influenced by the vitamin D level of patients, drug type, the total vitamin D dosage, the duration, administration frequency, and daily dosage of vitamin D supplementation. The infertile women (vitamin D level < 30 ng/mL) treated with the multicomponent drugs including vitamin D (10,000-50,000 IU or 50,000-500,000 IU), or got vitamin D 1000-10,000 IU daily, lasting for 30-60 days could achieve better pregnancy outcome. CONCLUSION: To the best of our knowledge, this is the first meta-analysis systematically investigated that moderate daily dosing of vitamin D supplementation could improve the clinical pregnancy rate of infertile women and reported the effects of vitamin D supplementation parameters on pregnancy outcomes. A larger sample size and high-quality RCTs are necessary to optimize the parameters of vitamin D supplementation to help more infertile patients benefit from this therapy.

Effects of sequential cleavage and blastocyst embryo transfer on pregnancy outcomes in patients with poor ovarian response.

The management of patients with poor ovarian response (POR) remains a major challenge for fertility specialists in in vitro fertilization-embryo transfer (IVF-ET). In this retrospective cohort study, we aimed to evaluate the clinical effect of sequential transfer on pregnancy outcomes in patients with POR. A total of 3579 POR patients who underwent the first frozen embryo transfer (FET) cycle were enrolled from January 2018 to April 2021. The patients were divided into three groups according to the embryo transfer (ET) strategy adopted: a study group that included POR patients in whom a cleavage-stage embryo (day 3) and a blastocyst (day 5/6) were transferred (sequential transfer group), and two control groups in whom two cleavage-stage embryos (D3-dET group) or two blastocysts (D5/6-dET group) were transferred. The study group was matched with the control groups at a ratio of 1:4 by propensity score matching (PSM). The main pregnancy outcomes measured were the live birth rate and multiple pregnancy rate. After PSM, the live birth rate in the sequential transfer group was significantly higher than that in the D3-dET group (44.2% vs. 34.3%, P = 0.019), and was similar to that in the D5/6-dET group (44.2% vs. 45.3%; P = 0.90). In addition, there was no increase in the risk of multiple pregnancy among POR patients undergoing sequential transfer compared with both D3-dET (26.7% vs. 25.6%, P = 0.85) and D5/6-dET (26.7% vs. 28.4%, P = 0.97) groups. These findings imply that sequential transfer is an effective option for POR patients and could be utilized after careful consideration.

Effect of sequential embryo transfer on in vitro fertilization and embryo transfer outcomes: a systematic review and meta-analysis.

Background: Sequential embryo transfer has been recognized as a strategy to increase pregnancy rates in women undergoing in vitro fertilization and embryo transfer (IVF-ET). However, its impact on assisted reproductive outcomes remains to be substantiated by robust evidence. This systematic review aims to summarize and analyze the available evidence to investigate the effect of sequential embryo transfer on assisted reproductive outcomes. Methods: A comprehensive literature search was executed across the Pubmed, Cochrane Library, Web of Science, and Scopus databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data were aggregated utilizing a random effects model, and the resultant outcomes were articulated as odds ratios (ORs) along with their 95% confidence intervals (CIs). Results: The pooled results revealed a statistically significant enhancement in reproductive outcomes for infertile patients undergoing sequential embryo transfer as evidenced by elevated rates of chemical pregnancy (OR = 1.67, 95% CI = 1.23-2.27), clinical pregnancy (OR = 1.78, 95% CI = 1.43-2.21), and ongoing pregnancy (OR = 1.54, 95% CI = 1.03-2.31). Compared with cleavage-stage embryo transfer, sequential transfer yielded superior outcomes in terms of chemical pregnancy rate (OR = 2.08, 95% CI = 1.35-3.19) and clinical pregnancy rate (OR = 1.78, 95% CI = 1.37-2.31). Furthermore, among the repeated implantation failure (RIF) cohort, sequential embryo transfer surpassed blastocyst-stage transfer, delivering a heightened chemical pregnancy rate (OR = 1.66, 95% CI = 1.19-2.53) and clinical pregnancy rate (OR = 1.65, 95% CI = 1.19-2.27). Conclusion: Our meta-analysis indicates that sequential transfer may enhance clinical pregnancy rate in a small subgroup of well-selected women. While promising, further evidence from prospective studies is needed.

Nomogram models to predict low fertilisation rate and total fertilisation failure in patients undergoing conventional IVF cycles.

OBJECTIVES: To establish visualised prediction models of low fertilisation rate (LFR) and total fertilisation failure (TFF) for patients in conventional in vitro fertilisation (IVF) cycles. DESIGN: A retrospective cohort study. SETTING: Data from August 2017 to August 2021 were collected from the electronic records of a large obstetrics and gynaecology hospital in Sichuan, China. PARTICIPANTS: A total of 11 598 eligible patients who underwent the first IVF cycles were included. All patients were randomly divided into the training group (n=8129) and the validation group (n=3469) in a 7:3 ratio. PRIMARY OUTCOME MEASURE: The incidence of LFR and TFF. RESULTS: Logistic regressions showed that ovarian stimulation protocol, primary infertility and initial progressive sperm motility were the independent predictors of LFR, while serum luteinising hormone and P levels before human chorionic gonadotropin injection and number of oocytes retrieved were the critical predictors of TFF. And these indicators were incorporated into the nomogram models. According to the area under the curve values, the predictive ability for LFR and TFF were 0.640 and 0.899 in the training set and 0.661 and 0.876 in the validation set, respectively. The calibration curves also showed good concordance between the actual and predicted probabilities both in the training and validation group. CONCLUSION: The novel nomogram models provided effective methods for clinicians to predict LFR and TFF in traditional IVF cycles.

An Individualized Recommendation for Controlled Ovary Stimulation Protocol in Women Who Received the GnRH Agonist Long-Acting Protocol or the GnRH Antagonist Protocol: A Retrospective Cohort Study.

Background: The GnRH agonist long-acting protocol and GnRH antagonist protocol are widely used in ovarian stimulation. Which protocol eliciting higher live birth rate for IVF/ICSI patients with different ages, different ovarian reserves and different body mass index (BMI) has not been studied. However, among these protocols, the one that elicits higher live birth in IVF/ICSI patients with different ages, ovarian reserves and body mass indexes (BMI) has not been identified. Methods: This was a retrospective cohort study about 8579 women who underwent the first IVF-ET from January, 2018 to August, 2021. Propensity Score Matching (PSM) was used to improve the comparability between two protocols. Results: After PSM, significant higher live birth rates were found in the GnRH agonist long-acting protocol compared to GnRH antagonist protocol (44.04% vs. 38.32%) (p<0.001). Stratified analysis showed that for those with AMH levels between 3 ng/ml and 6 ng/ml, with BMI ≥ 24 kg/m2 and were aged ≥ 30 years old, and for those women with BMI < 24kg/m2 and were aged ≥30 years whose AMH levels were ≤ 3ng/ml, the GnRH agonist long-acting protocol was more likely to elicit live births [OR (95%CI), 2.13(1.19,3.80)], [OR (95%CI), 1.41(1.05,1.91)]. However, among women with BMI ≥ 24kg/m2 and were aged ≥30 years whose AMH levels were ≤ 3ng/ml, the GnRH agonist long-acting protocol had a lower possibility of eliciting live births [OR (95%CI), 0.54(0.32,0.90)]. Also, among women with AMH levels between 3 ng/ml and 6 ng/ml, with BMI ≥ 24 kg/m2 and with age < 30 years and for those with AMH levels between 3 ng/ml and 6 ng/ml, regardless of age, and with BMI<24kg/m2,, the possibility of live births was similar between the two protocols [OR (95%CI), 1.06(0.60,1.89)], [OR (95%CI), 1.38(0.97,1.97)], [OR (95%CI), 0.99(0.72,1.37)]. Among the women with AMH levels ≤ 3 ng/ml and with were aged < 30years, regardless of BMI, the possibility of live birth was similar between the two protocols [OR (95%CI), 1.02(0.68,1.54)], [OR (95%CI), 1.43(0.68,2.98)]. Moreover, among women with AMH levels ≥ 6ng/ml, the possibility of live birth was similar between the two protocols [OR (95%CI),1.42(0.75,2.69)], [OR (95%CI),1.02(0.19,5.35)], [OR (95%CI), 1.68(0.81,3.51)], [OR (95%CI), 0.51(0.10,2.55)]. Conclusions: The suitability of the GnRH agonist long-acting protocol or GnRH antagonist protocol to infertility patients is dependent on specific biological characteristics of the patients.

Human Umbilical Cord Mesenchymal Stem Cells Encapsulated with Pluronic F-127 Enhance the Regeneration and Angiogenesis of Thin Endometrium in Rat via Local IL-1ß Stimulation.

Thin endometrium (< 7 mm) could cause low clinical pregnancy, reduced live birth, increased spontaneous abortion, and decreased birth weight. However, the treatments for thin endometrium have not been well developed. In this study, we aim to determine the role of Pluronic F-127 (PF-127) encapsulation of human umbilical cord mesenchymal stem cells (hUC-MSCs) in the regeneration of thin endometrium and its underlying mechanism. Thin endometrium rat model was created by infusion of 95% ethanol. Thin endometrium modeled rat uterus were treated with saline, hUC-MSCs, PF-127, or hUC-MSCs plus PF-127 separately. Regenerated rat uterus was measured for gene expression levels of angiogenesis factors and histological morphology. Angiogenesis capacity of interleukin-1 beta (IL-1ß)-primed hUC-MSCs was monitored via quantitative polymerase chain reaction (q-PCR), Luminex assay, and tube formation assay. Decreased endometrium thickness and gland number and increased inflammatory factor IL-1ß were achieved in the thin endometrium rat model. Embedding of hUC-MSCs with PF-127 could prolong the hUC-MSCs retaining, which could further enhance endometrium thickness and gland number in the thin endometrium rat model via increasing angiogenesis capacity. Conditional medium derived from IL-1ß-primed hUC-MSCs increased the concentration of angiogenesis factors (basic fibroblast growth factor (bFGF), vascular endothelial growth factors (VEGF), and hepatocyte growth factor (HGF)). Improvement in the thickness, number of glands, and newly generated blood vessels could be achieved by uterus endometrium treatment with PF-127 and hUC-MSCs transplantation. Local IL-1ß stimulation-primed hUC-MSCs promoted the release of angiogenesis factors and may play a vital role on thin endometrium regeneration.

Effect of artificial cycle with or without GnRH-a pretreatment on pregnancy and neonatal outcomes in women with PCOS after frozen embryo transfer: a propensity score matching study.

BACKGROUND: In frozen embryo transfer (FET), there is limited consensus on the best means of endometrial preparation in terms of the reproductive outcomes in women with polycystic ovary syndrome (PCOS). The present study aimed to compare the pregnancy and neonatal outcomes following artificial cycle FET (AC-FET) with or without gonadotropin-releasing hormone agonist (GnRH-a) pretreatment among women with PCOS. METHODS: A total of 4503 FET cycles that satisfied the inclusion criteria were enrolled in this retrospective cohort study between 2015 and 2020. The GnRH-a group received GnRH-a pretreatment while the AC-FET group did not. Propensity score matching (PSM) method and multivariate logistic regression analysis were performed to adjust for potential confounding factors. RESULTS: After PSM, women in the GnRH-a group suffered a significantly lower miscarriage rate (11.2% vs. 17.1%, P = 0.033) and a higher live birth rate (LBR) compared with those in the AC-FET group (63.1% vs. 56.8%, P = 0.043). No differences were observed in the rates of biochemical pregnancy, clinical pregnancy and ectopic pregnancy between the two groups. A higher mean gestational age at birth was observed in the GnRH-a group than in the AC-FET group (39.80 ± 2.01 vs. 38.17 ± 2.13, P = 0.009). The incidence of neonatal preterm birth (PTB) in the GnRH-a group was lower than that in the AC-FET group (7.4% vs. 14.9%, P = 0.009). Singleton newborns conceived after GnRH-a group were more likely to be small for gestational age (SGA) than those born after AC-FET group (16.4% vs. 6.8%, P = 0.009). However, no significant differences were found between the two groups in terms of mean birthweight, apgar score, the rates of macrosomia, large for gestational age and low birth weight. CONCLUSION(S): In women with PCOS who underwent AC-FET, GnRH-a pretreatment was significantly associated with a higher live birth rate and a reduced risk of neonatal PTB. However, there was a concomitant increase in the risk of developing SGA babies.

Analysis of clinical outcomes of vitrified-warmed embryo transfer after IVF/ICSI at high altitude (3650 m) in Tibet.

RESEARCH QUESTION: What are the pregnancy outcomes of IVF vitrified-warmed embryo transfer (IVF-FET) carried out in a clinical setting located at an altitude of 3650 m in Tibet, China? DESIGN: A retrospective analysis of 238 infertility couples (n = 344 treatment cycles) who underwent FET treatment at the Xizang Fukang Hospital, Tibet. The overall clinical pregnancy rate, implantation rate, live birth rate, miscarriage rate and ectopic pregnancy rate were statistically analysed. Women were categorized into two groups based on age: 35 years or younger (n = 265 cycles) and over 35 years (n = 79 cycles). The general characteristics and pregnancy outcomes were compared between the two groups. RESULTS: The clinical pregnancy rate, implantation rate, live birth rate, miscarriage rate, and ectopic pregnancy rate of the 344 FET cycles were 43.02%, 30.90%, 35.17%, 18.24% and 1.35%, respectively. The clinical pregnancy rate (46.04% versus 32.91%), implantation rate (33.92% versus 21.01%) and live birth rate (38.11% versus 25.32%) in the group aged 35 years or younger were significantly greater than those in the group aged over 35 years (P = 0.039, P = 0.004, P = 0.037). The miscarriage rate (17.21% versus 23.08%) and ectopic pregnancy rate (0.82% versus 3.85%) were not significantly different in the two groups. CONCLUSION: A live birth rate of 35.17% can be achieved with IVF-FET in high-altitude areas (3650 m above sea level). Maternal age is still an important determinant of clinical pregnancy rate, implantation rate, and live birth rate of infertile patients in high-altitude areas.

Error analysis of a rotating-metasurface polarimeter.

Polarimeters, which measure the polarization states of light directly, are essentially desired in many areas of science and technology. In our previous work, we have constructed a polarimeter based on a rotating-metasurface, and the polarization Stokes parameters of the light were measured with the known Mueller elements of the metasurface. Here, we further perform the error analysis of the metasurface polarimeter. The errors in the measured Stokes parameters have been formulated for the errors in Mueller elements of the metasurface. This analysis can be used to evaluate and minimize the errors of the metasurface polarimeter.

lncRNA HCG11 suppresses human osteosarcoma growth through upregulating p27 Kip1.

Osteosarcoma (OS) is a common malignant bone cancer threatening children and young adults. Emerging evidence indicates that long non-coding RNAs (lncRNAs) play crucial roles in the progression of OS. Herein, we want to clarify the roles of lncRNA human leukocyte antigen complex group 11 (HCG11) in OS. Our data revealed that HCG11 expression is decreased in OS, which is a result of transcriptional repression of YY1. Low HCG11 level is closely associated with larger tumor size and shorter overall survival of OS patients. HCG11 negatively regulates cell proliferation, cell cycle, DNA replication in vitro and tumor growth in vivo. HCG11 can raise p27 Kip1 expression via binding to miR-942-5p and IGF2BP2, and p27 Kip1 acts as a key effector for HCG11 exerting biological functions. In conclusion, HCG11 is downregulated in OS, and restrains OS growth both in vitro and in vivo by raising p27 Kip1 expression via binding to miR-942-5p and IGF2BP2.

Human sperm tsRNA as potential biomarker and therapy target for male fertility.

Infertility caused by male factors is routinely diagnosed by assessing traditional semen parameters. Growing evidence has indicated that the tsRNAs carried in sperm act as epigenetic factors and potential biomarkers for the assessment of sperm quality. We recently demonstrated that tRNAGln-TTG derived small RNAs played notable roles in the first cleavage of a porcine embryo. However, the function of human sperm tRNAGln-TTG derived small RNAs as a diagnostic biomarker and its role in early embryo development remains unclear. In this study, we found that human sperm tRNAGln-TTG derived small RNAs were highly associated with sperm quality. By microinjecting the antisense sequence into human tripronuclear (3PN) zygotes followed by single-cell RNA-sequencing, we found that human sperm tRNAGln-TTG derived small RNAs participated in the development of a human embryo. Furthermore, Gln-TTGs might influence embryonic genome activation by modulating noncoding RNA processing. These findings demonstrated that human sperm tRNAGln-TTG derived small RNAs could be potential diagnostic biomarkers and could be used as a clinical target for male infertility.

[Current progress in single sperm cryopreservation].

Sperm cryopreservation has been widely used in assisted reproduction, but conventional techniques are not suitable for the cryopreservation of small numbers of sperm. The application of the single sperm cryopreservation technique has significantly improved the clinical treatment of cryptozoospermia and non-obstructive azoospermia. Ever since Cohen et al first developed the method of single sperm cryopreservation in 1997, constant efforts have been made to develop the carriers for this technique. In this review, we mainly discuss the existing methods and clinical outcomes of single sperm cryopreservation.