Live Birth with or without Preimplantation Genetic Testing for Aneuploidy.

BACKGROUND: Embryo selection with preimplantation genetic testing for aneuploidy (PGT-A) may improve pregnancy outcomes after initial embryo transfer. However, it remains uncertain whether PGT-A improves the cumulative live-birth rate as compared with conventional in vitro fertilization (IVF). METHODS: In this multicenter, randomized, controlled trial, we randomly assigned subfertile women with three or more good-quality blastocysts to undergo either PGT-A or conventional IVF; all the women were between 20 and 37 years of age. Three blastocysts were screened by next-generation sequencing in the PGT-A group or were chosen by morphologic criteria in the conventional-IVF group and then were successively transferred one by one. The primary outcome was the cumulative live-birth rate after up to three embryo-transfer procedures within 1 year after randomization. We hypothesized that the use of PGT-A would result in a cumulative live-birth rate that was no more than 7 percentage points higher than the rate after conventional IVF, which would constitute the noninferiority margin for conventional IVF as compared with PGT-A. RESULTS: A total of 1212 patients underwent randomization, and 606 were assigned to each trial group. Live births occurred in 468 women (77.2%) in the PGT-A group and in 496 (81.8%) in the conventional-IVF group (absolute difference, -4.6 percentage points; 95% confidence interval [CI], -9.2 to -0.0; P<0.001). The cumulative frequency of clinical pregnancy loss was 8.7% and 12.6%, respectively (absolute difference, -3.9 percentage points; 95% CI, -7.5 to -0.2). The incidences of obstetrical or neonatal complications and other adverse events were similar in the two groups. CONCLUSIONS: Among women with three or more good-quality blastocysts, conventional IVF resulted in a cumulative live-birth rate that was noninferior to the rate with PGT-A. (Funded by the National Natural Science Foundation of China and others; ClinicalTrials.gov number, NCT03118141.).

Prevalence and molecular characterization of multi-resistant Escherichia coli isolates from clinical bovine mastitis in China.

Different antibiotics are used to treat mastitis in dairy cows that is caused by Escherichia coli (E. coli). Antimicrobial resistance in food-producing animals in China has been monitored since 2000. Surveillance data have shown that the prevalence of multiresistant E. coli in animals has increased significantly. This study aimed to investigate the occurrence and molecular characteristics of resistance determinants in E. coli strains (n = 105) obtained from lactating cows with clinical bovine mastitis (CBM) in China. A total of 220 cows with clinical mastitis, which has swollen mammary udder with reduced and red or gangrenous milk, were selected from 5000 cows. The results showed 94.3% of the isolates were recognized as multidrug resistant. The isolates (30.5%) were positive for the class I integrase gene along with seven gene cassettes that were accountable for resistance to trimethoprim resistance (dfrA17, dfr2d and dfrA1), aminoglycosides resistance (aadA1 and aadA5) and chloramphenicol resistance (catB3 and catB2), respectively. The blaTEM gene was present in all the isolates, and these carried the blaCTX gene. A double mutation in gyrA (i.e., Ser83Leu and Asp87Asn) was observed in all fluoroquinolone-resistant isolates. In total, nine fluoroquinolone-resistant E. coli isolates were identified with five different types of mutations in parC. In four (44.4%) isolates, Ser458Ala was present in parE, and in all nine (9/9) fluoroquinolone-resistant isolates, Pro385Ala was present in gyrB. Meanwhile, fluoroquinolone was observed as highly resistant, especially in isolates with gyrA and parC mutations. In summary, the findings of this research recognize the fluoroquinolone resistance mechanism and disclose integron prevalence and ESBLs in E. coli isolates from lactating cattle with CBM.

Estrogen valerate pretreatment with the antagonist protocol does not increase oocyte retrieval in patients with low ovarian response: a randomized controlled trial.

STUDY QUESTION: Does luteal phase estrogen valerate pretreatment improve oocyte yield and clinical outcomes in patients with low ovarian response during ovarian stimulation with the antagonist protocol? SUMMARY ANSWER: Pretreatment with oral estrogen valerate from Day 7 after ovulation to Day 2 of the next menstrual cycle did not increase oocyte yield in patients with a low ovarian response compared to no pretreatment. WHAT IS KNOWN ALREADY: Previous studies showed that patients with a normal ovarian response can obtain better clinical outcomes after pretreatment with estrogen in the antagonist protocol. For patients with advanced age and low ovarian response, it remains unclear if estrogen valerate pretreatment with the antagonist protocol yields more oocytes and improves pregnancy outcomes. STUDY DESIGN, SIZE, DURATION: This non-blinded randomized controlled trial (RCT) was conducted between November 2017 and March 2021. Participants were 552 women with low response who requested IVF treatment. The primary endpoint was comparison of the total number of retrieved oocytes between the two groups. The secondary endpoints were the total number of retrieved metaphase II (MII) oocytes, duration and total dosage of recombinant FSH (rFSH), good-quality embryo rate and clinical pregnancy rate. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study was conducted at a reproductive center. The RCT enrolled 552 infertile women with a low ovarian response (according to the Bologna criteria) who were undergoing IVF. In the study group, on Day 7 after ovulation patients were administered oral estrogen valerate (2 mg twice a day) until Day 2 of their next menstruation. Ovary stimulation was performed using rFSH, and a GnRH antagonist (0.25 mg/day) was started when a dominant follicle had a mean diameter ≥13 mm. MAIN RESULTS AND THE ROLE OF CHANCE: No significant difference was observed in the number (mean [SD]) of oocytes retrieved from the estrogen valerate pretreatment and control group (3.2 [2.8] versus 3.4 [2.6], respectively). The treatment difference was -0.18 (95% CI -0.67, 0.32, P = 0.49). No significant differences were observed in the number of MII oocytes (2.9 [2.5] versus 3.1 [2.4], mean difference -0.23, 95% CI (-0.69, 0.23), P = 0.16) and good-quality embryos (1.0 [1.3] versus 1.20 [1.6], mean difference -0.23, 95% CI (-0.50, 0.04), P = 0.19) between the two groups. The duration of rFSH treatment was significantly longer in the estrogen valerate pretreatment group than in the control group (10.3 [2.2] versus 8.6 [2.1] days, mean difference 1.7, 95% CI (1.3, 2.2), P = 0.00), and the total rFSH dosage was significantly higher in the estrogen valerate pretreatment group than in the control group (3081 [680] versus 2548 [649] IU, mean difference 553.7, 95% CI (405.8, 661.6), P = 0.00). The clinical pregnancy rate in the pretreatment group (19.3% [23/119]) was not significantly different from that in the control group (28.7% [43/150]). The mean difference was -0.09, 95% CI (-0.20, 0.01), P = 0.08. LIMITATIONS, REASONS FOR CAUTION: The major limitation was the high dropout rate of patients. Some patients did not return to the hospital for treatment because of predicted low success rates and for economic reasons. In addition, it is possible that the fixed dose of 300 IU rFSH was not sufficient to see differences in oocyte yield between the groups. WIDER IMPLICATIONS OF THE FINDINGS: Estrogen valerate pretreatment with an antagonist protocol did not increase oocyte yield in patients with low ovarian response. Similar to the number of retrieved oocytes, there was no significant difference in clinical pregnancy rate between estrogen pretreatment group and control group. More research is needed on whether patients with low ovarian response need pretreatment and which pretreatment is more appropriate. STUDY FUNDING/COMPETING INTEREST(S): This study was supported in part by a research grant from the Investigator-Initiated Studies Program of MSD (China) Holding Co., Ltd. and Organon (Shanghai) Pharmaceutical Technology Co., Ltd. (Grant number: IIS 56284). The authors declare that they have no competing interests regarding authorship or publication of this study. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT03300518. TRIAL REGISTRATION DATE: 28 September 2017. DATE OF FIRST PATIENT'S ENROLMENT: 15 November 2017.

Estrogen-dependent KCa1.1 modulation is essential for retaining neuroexcitation of female-specific subpopulation of myelinated Ah-type baroreceptor neurons in rats.

Female-specific subpopulation of myelinated Ah-type baroreceptor neurons (BRNs) in nodose ganglia is the neuroanatomical base of sexual-dimorphic autonomic control of blood pressure regulation, and KCa1.1 is a key player in modulating the neuroexcitation in nodose ganglia. In this study we investigated the exact mechanisms underlying KCa1.1-mediated neuroexcitation of myelinated Ah-type BRNs in the presence or absence of estrogen. BRNs were isolated from adult ovary intact (OVI) or ovariectomized (OVX) female rats, and identified electrophysiologically and fluorescently. Action potential (AP) and potassium currents were recorded using whole-cell recording. Consistently, myelinated Ah-type BRNs displayed a characteristic discharge pattern and significantly reduced excitability after OVX with narrowed AP duration and faster repolarization largely due to an upregulated iberiotoxin (IbTX)-sensitive component; the changes in AP waveform and repetitive discharge of Ah-types from OVX female rats were reversed by G1 (a selective agonist for estrogen membrane receptor GPR30, 100 nM) and/or IbTX (100 nM). In addition, the effect of G1 on repetitive discharge could be completely blocked by G15 (a selective antagonist for estrogen membrane receptor GPR30, 3 µM). These data suggest that estrogen deficiency by removing ovaries upregulates KCa1.1 channel protein in Ah-type BRNs, and subsequently increases AP repolarization and blunts neuroexcitation through estrogen membrane receptor signaling. Intriguingly, this upregulated KCa1.1 predicted electrophysiologically was confirmed by increased mean fluorescent intensity that was abolished by estrogen treatment. These electrophysiological findings combined with immunostaining and pharmacological manipulations reveal the crucial role of KCa1.1 in modulation of neuroexcitation especially in female-specific subpopulation of myelinated Ah-type BRNs and extend our current understanding of sexual dimorphism of neurocontrol of BP regulation.

Intrauterine transplantation of autologous menstrual blood stem cells increases endometrial thickness and pregnancy potential in patients with refractory intrauterine adhesion.

AIM: This study was designed to evaluate the effects of intrauterine transplantation of menstrual blood stem cells (MenSCs) on endometrial thickness and pregnancy outcomes in patients with refractory intrauterine adhesion (IUA). METHODS: This study included a group of infertile women (n = 12, age 22-40 years), with refractory IUA. Autologous MenSCs isolated from the women's menstrual blood were expanded in vitro and transplanted into their uteruses, followed by hormone replacement therapy. Transvaginal ultrasound examination was performed to assess the endometrial thickness. Transabdominal ultrasound was conducted to detect pregnancy outcome. RESULTS: Autologous MenSCs were successfully isolated and expanded from menstrual blood and transplanted into the uterus of each patient. A significant improvement of the endometrial thickness was observed from 3.9 ± 0.9 to 7.5 ± 0.6 mm (P < 0.001). No adverse reaction was observed. The duration of menstruation was increased from 2.4 ± 0.7 to 5.3 ± 0.6 days (P < 0.001). Five out of 12 patients achieved clinical pregnancy and the pregnancy rate was 41.7%. CONCLUSIONS: Intrauterine transplantation of autologous MenSCs results in regeneration of endometrium, a prolongation of menstrual duration and an increase rate of pregnancy in patients with refractory IUA.

Inhibition of Endometrial Tiam1/Rac1 Signals Induced by miR-22 Up-Regulation Leads to the Failure of Embryo Implantation During the Implantation Window in Pregnant Mice.

This study assessed first the impact of endometrial Tiam1/Rac1 signals and microRNA-22 (miR-22) on embryo implantation in mice, and then the expression of the above three genes in the endometrium during the embryo implantation window in the natural menstrual cycle in women with repeated implantation failure (RIF) after in vitro fertilization treatment. Four hundred fifty-two Kun-ming female mice and 200 women (70 infertility patients with RIF, 130 women as controls) were entered into this study. Endometrial Tiam1/Rac1 signals and miR-22 expression were studied in clinical and mouse samples and serum estrogen (E2) and progesterone (P) were analyzed in clinical subjects. A pregnant mouse model based on an endometrial miR-22 and Tiam1 mRNA expression trend of patients with RIF was constructed and then the embryo implantation numbers were analyzed, and an ovariectomized mouse model was used to assess correlations of expression of these three genes with E2 and P. The results showed that during the embryo implantation window in the natural menstrual cycle, endometrial miR-22 was significantly higher whereas Tiam1/Rac1 signals were notably lower in patients with RIF than in controls, and the P:E2 ratio was statistically lower in the RIF group. Tiam1/Rac1 signal down-regulation and miR-22 up-regulation contributed to the inhibition of embryo implantation in mice. We also found a suppressive effect of miR-22 up-regulation on Tiam1/Rac1 signal expression, and reciprocal regulation of E2 and P for these three genes' expression in mice. In conclusion, miR-22 up-regulation and Tiam1/Rac1 signal down-regulation inhibited embryo implantation in mice; this mechanism may be partially due to the suppressive effect of miR-22 on Tiam1 expression, and is regulated to some extent by serum E2 and P. Our findings provide evidence that endometrial Tiam1/Rac1 signal down-regulation along with miR-22 up-regulation during embryo implantation window in the natural menstrual cycle may be one of the reasons for the failure of embryo implantation in patients with RIF.

BRD4 phosphorylation regulates the structure of chromatin nanodomains.

The interplay between chromatin structure and phase-separating proteins is an emerging topic in cell biology with implications for understanding disease states. Here, we investigate the functional relationship between bromodomain protein 4 (BRD4) and chromatin architecture. By combining molecular dynamics simulations with live-cell imaging, we demonstrate that BRD4, when mutated at specific N-terminus sites, significantly impacts nucleosome nanodomain (NN) organization and dynamics. Our findings reveal that enhanced chromatin binding activity of BRD4 condenses NNs, while both loss or gain of BRD4 chromatin binding reduced diffusion of single nucleosomes, suggesting a role for BRD4 in the regulation of nanoscale chromatin architecture and the chromatin microenvironment. These observations shed light on the nuanced regulation of chromatin structure by BRD4, offering insights into its role in maintaining the nuclear architecture and transcriptional activity.

Personalized neoantigen cancer vaccines: current progression, challenges and a bright future.

Tumor neoantigens possess specific immunogenicity and personalized therapeutic vaccines based on neoantigens which have shown promising results in some clinical trials, with broad application prospects. However, the field is developing rapidly and there are currently few relevant review articles. Summarizing and analyzing the status of global personalized neoantigen vaccine clinical trials will provide important data for all stakeholders in drug development. Based on the Trialtrove database, a retrospective analysis was conducted using trial quantity as a key indicator for neo-adjuvant and adjuvant therapy anti-PD-1/PD-L1 clinical trials initiated before the end of 2022. The time trend of newly initiated trials was investigated. The sponsor type, host country, treatment mode, combination strategy, tested drugs, and targeted cancer types of these trials were summarized. As of December 2022, a total of 199 trials were included in the analysis. Among these studies, Phase I studies were the most numerous (119, 59.8%), and Phase I studies have been the predominant study type since 2015. Peptide vaccines were the largest neoantigen vaccines type, accounting for 64.8% of all clinical trials. Based on peptide delivery platforms, the proportion of trials was highest for the DC system (32, 16.1%), followed by LNP (11, 5.5%), LPX (11, 5.5%), and viruses (7, 3.5%). Most vaccines were applied in trials as a monotherapy (133/199, 66.8%), meanwhile combining immunotherapeutic drugs was the most common form for combination therapy. In terms of indications, the largest number of trials involved three or more unspecified solid tumors (50/199, 25.1%), followed by non-small cell lung cancer (24/199, 12.1%) and pancreatic cancer (15/199, 7.5%). The clinical development of personalized neoantigen cancer vaccines is still in the early stage. A clear shift in delivery systems from peptides to DC and liposomal platforms, with the largest number of studies in Asia, collectively marks a new era in the field. The adjuvant or maintenance therapy, and the combination treatment with ICIs are becoming the important clinical development orientation. As research on tumor-immune interactions intensifies, the design, development, and application of neoantigen vaccines are bound to develop rapidly, which will bring a new revolution in the future cancer treatment.

Curriculum-Based Deep Reinforcement Learning for Quantum Control.

Deep reinforcement learning (DRL) has been recognized as an efficient technique to design optimal strategies for different complex systems without prior knowledge of the control landscape. To achieve a fast and precise control for quantum systems, we propose a novel DRL approach by constructing a curriculum consisting of a set of intermediate tasks defined by fidelity thresholds, where the tasks among a curriculum can be statically determined before the learning process or dynamically generated during the learning process. By transferring knowledge between two successive tasks and sequencing tasks according to their difficulties, the proposed curriculum-based DRL (CDRL) method enables the agent to focus on easy tasks in the early stage, then move onto difficult tasks, and eventually approaches the final task. Numerical comparison with the traditional methods [gradient method (GD), genetic algorithm (GA), and several other DRL methods] demonstrates that CDRL exhibits improved control performance for quantum systems and also provides an efficient way to identify optimal strategies with few control pulses.

Proteomes from AMPK-inhibited peripheral blood mononuclear cells suppress the progression of breast cancer and bone metastasis.

Background: During a developmental process, embryos employ varying tactics to remove unwanted cells. Using a procedure analogous to some of the embryonic cells, we generated a tumor-eliminating conditioned medium (CM) from AMPK-inhibited lymphocytes and monocytes in peripheral blood mononuclear cells (PBMCs). Methods: AMPK signaling was inhibited by the application of a pharmacological agent, Dorsomorphin, and the therapeutic effects of their conditioned medium (CM) were evaluated using in vitro cell cultures, ex vivo breast cancer tissues, and a mouse model of mammary tumors and tumor-induced osteolysis. The regulatory mechanism was evaluated using mass spectrometry-based proteomics, Western blotting, immunoprecipitation, gene overexpression, and RNA interference. Results: While AMPK signaling acted mostly anti-tumorigenic, we paradoxically inhibited it to build induced tumor-suppressing cells and their tumor-eliminating CM. In a mouse model of breast cancer, the application of AMPK-inhibited lymphocyte-derived CM reduced mammary tumors additively to a chemotherapeutic agent, Taxol. It also prevented bone loss in the tumor-bearing tibia. Furthermore, the application of CM from the patient-derived peripheral blood diminished ex vivo breast cancer tissues isolated from the same patients. Notably, proteins enriched in CM included Moesin (MSN), Enolase 1 (ENO1), and polyA-binding protein 1 (PABPC1), which are considered tumorigenic in many types of cancer. The tumor-suppressing actions of MSN and ENO1 were at least in part mediated by Metadherin (Mtdh), which is known to promote metastatic seeding. Conclusion: We demonstrated that PBMCs can be used to generate tumor-suppressive proteomes, and extracellular tumor-suppressing proteins such as MSN, ENO1, and PABPC1 are converted from tumor-promoting factors inside cancer cells. The results support the possibility of developing autologous blood-based therapy, in which tumor-suppressing proteins are enriched in engineered PBMC-derived CM by the inhibition of AMPK signaling.

Suppression of osteosarcoma progression by engineered lymphocyte-derived proteomes.

Cancer cells tend to develop resistance to chemotherapy and enhance aggressiveness. A counterintuitive approach is to tame aggressiveness by an agent that acts opposite to chemotherapeutic agents. Based on this strategy, induced tumor-suppressing cells (iTSCs) have been generated from tumor cells and mesenchymal stem cells. Here, we examined the possibility of generating iTSCs from lymphocytes by activating PKA signaling for suppressing the progression of osteosarcoma (OS). While lymphocyte-derived CM did not present anti-tumor capabilities, the activation of PKA converted them into iTSCs. Inhibiting PKA conversely generated tumor-promotive secretomes. In a mouse model, PKA-activated CM suppressed tumor-induced bone destruction. Proteomics analysis revealed that moesin (MSN) and calreticulin (Calr), which are highly expressed intracellular proteins in many cancers, were enriched in PKA-activated CM, and they acted as extracellular tumor suppressors through CD44, CD47, and CD91. The study presented a unique option for cancer treatment by generating iTSCs that secret tumor-suppressive proteins such as MSN and Calr. We envision that identifying these tumor suppressors and predicting their binding partners such as CD44, which is an FDA-approved oncogenic target to be inhibited, may contribute to developing targeted protein therapy.

Deep Reinforcement Learning With Quantum-Inspired Experience Replay.

In this article, a novel training paradigm inspired by quantum computation is proposed for deep reinforcement learning (DRL) with experience replay. In contrast to the traditional experience replay mechanism in DRL, the proposed DRL with quantum-inspired experience replay (DRL-QER) adaptively chooses experiences from the replay buffer according to the complexity and the replayed times of each experience (also called transition), to achieve a balance between exploration and exploitation. In DRL-QER, transitions are first formulated in quantum representations and then the preparation operation and depreciation operation are performed on the transitions. In this process, the preparation operation reflects the relationship between the temporal-difference errors (TD-errors) and the importance of the experiences, while the depreciation operation is taken into account to ensure the diversity of the transitions. The experimental results on Atari 2600 games show that DRL-QER outperforms state-of-the-art algorithms, such as DRL-PER and DCRL on most of these games with improved training efficiency and is also applicable to such memory-based DRL approaches as double network and dueling network.

Bradykinin-mediated estrogen-dependent depressor response by direct activation of female-specific distribution of myelinated Ah-type baroreceptor neurons in rats.

AIM: To understand the direct impact of bradykinin in autonomic control of circulation through baroreflex afferent pathway. METHODS: The mean arterial pressure (MAP) was monitored while bradykinin and its agonists were applied via nodose (NG) microinjection, the expression of bradykinin receptors (BRs) in the NG (1st -order) and nucleus tractus solitarius (NTS, 2nd -order) were tested in adult male, age-matched female, and ovariectomized rats under physiological and hypertensive conditions. Additionally, bradykinin-induced depolarization was also tested in identified baroreceptor and baroreceptive neurons using whole-cell patch-clamp technique. RESULTS: Under physiological condition, bradykinin-induced dose- and estrogen-dependent reductions of MAP with lower estimated EC50 in females. B2 R agonist mediated more dramatic MAP reduction with long-lasting effect compared with B1 R activation. These functional observations were consistent with the molecular and immunostaining evidences. However, under hypertensive condition, the MAP reduction was significantly less dramatic in N' -Nitro-L-Arginine-methyl ester (L-NAME) induced secondary and spontaneous hypertension rats in males compared with female rats. Electrophysiological data showed that bradykinin-elicited concentration-dependent membrane depolarization with discharges during initial phase in identified myelinated Ah-types baroreceptor neurons, not myelinated A-types; while, higher concentration of bradykinin was required for depolarization of unmyelinated C-types without initial discharges. CONCLUSION: These datasets have demonstrated for the first time that bradykinin mediates direct activation of baroreflex afferent function to trigger estrogen-dependent depressor response, which is due mainly to the direct activation/neuroexcitation of female-specific myelinated Ah-type baroreceptor neurons leading to a sexual dimorphism in parasympathetic domination of blood pressure regulation via activation of B2 R/B1 R expression in baroreflex afferent pathway.

Learning-Based Quantum Robust Control: Algorithm, Applications, and Experiments.

Robust control design for quantum systems has been recognized as a key task in quantum information technology, molecular chemistry, and atomic physics. In this paper, an improved differential evolution algorithm, referred to as multiple-samples and mixed-strategy DE (msMS_DE), is proposed to search robust fields for various quantum control problems. In msMS_DE, multiple samples are used for fitness evaluation and a mixed strategy is employed for the mutation operation. In particular, the msMS_DE algorithm is applied to the control problems of: 1) open inhomogeneous quantum ensembles and 2) the consensus goal of a quantum network with uncertainties. Numerical results are presented to demonstrate the excellent performance of the improved machine learning algorithm for these two classes of quantum robust control problems. Furthermore, msMS_DE is experimentally implemented on femtosecond (fs) laser control applications to optimize two-photon absorption and control fragmentation of the molecule CH2BrI. The experimental results demonstrate the excellent performance of msMS_DE in searching for effective fs laser pulses for various tasks.

The role of T-lymphoma invasion and metastasis inducing protein 1 in early pregnancy in mice.

T-lymphoma invasion and metastasis inducing protein 1 (Tiam1) is involved in tumorigenesis processes, including cell migration, adhesion and invasion, proteolysis, cytoskeleton reorganization, cell morphological transformation and intracellular signaling. These processes are also critical for embryo implantation, although the role of Tiam1 during embryo implantation remains poorly understood. The aim of this study was to investigate the spatio-temporal expression of Tiam1 in endometria of mice comparing early pregnancy and non-pregnancy. Fluorescent quantitative-PCR and immunohistochemical analysis showed that the expression of Tiam1 mRNA and protein in endometria of pregnant mice was higher than that of non-pregnant mice, and gradually increased from Day 1 of pregnancy reaching a maximum level on Day 5 and then declining on Days 6 and 7. Immunohistochemistry showed that Tiam1 protein was present in luminal epithelium from Days 3-5 of pregnancy and in gland epithelium from Days 4 to 6 and enhanced significantly in stromal cells on Day 5, regarded as the 'implantation window' period. The number of implantation sites was greatly decreased by the intrauterine injection with anti-Tiam1 polyclonal antibody in the early morning of the Day 4 of pregnancy. These findings suggest that Tiam1 might play an important role in embryo implantation in mice.

Expression of phosphatase and tensin homolog deleted on chromosome ten in mouse endometrium and its effect during blastocyst implantation.

The present study was aimed to investigate the expression of tumor suppressor gene PTEN (phosphatase and tensin homolog deleted on chromosome ten) in mouse endometrium during early pregnancy and its possible role during blastocyst implantation. Real-time fluorescent quantitative PCR (FQ-PCR) and immunohistochemical techniques were applied to detect PTEN mRNA and protein expressions in endometrium in un-pregnant and pregnant mice on days 1, 3, 4, 5, 7 of pregnancy, respectively. In addition, PTEN antisense oligonucleotide was injected into the horns of uterus in pregnant mice on day 3 of pregnancy and its effects on blastocyst implantation was detected in vivo. The higher expressions of PTEN mRNA and protein were observed in pregnant mice compared with that in un-pregnant mice, with a steady increasing from day 1 to 7 and reaching the maximal level on day 5 of pregnancy. PTEN antisense oligonucleotide decreased the number of implanted blastocysts compared with saline. The results suggest that PTEN might associate with apoptosis of luminal epithelial and decidual cells, coordinating decidualization of endometrium and invasion of trophoblastic cells. Thus, PTEN may participate in the process of blastocyst implantation in mice.

Expression of transcriptional repressor Slug gene in mouse endometrium and its effect during embryo implantation.

Slug, a member of the Snail family of zinc-finger transcription factors, is involved in regulating embryonic development and tumorigenesis. The aim of this study was to investigate the expression of Slug in mouse endometrium during early pregnancy and its possible role during embryo implantation. Fluorescence quantitative polymerase chain reaction and immunohistochemistry were applied to detect Slug mRNA and Slug protein expression in endometrium of nonpregnant and early pregnant mice, respectively. The expressions of Slug mRNA and its protein in pregnant group were higher than that in nonpregnant group and gradually increased from pregnancy day 1, reaching its maximum level on day 4 and then declining on days 5, 6, and 7. Immunohistochemistry showed that Slug protein was mainly present in luminal epithelium from pregnancy days 2 to 5 and in glandular epithelium from days 2 to 6 and enhanced significantly in stromal cells on days 4, 5, and 6. The number of embryos implanted was greatly decreased after Slug function in mouse endometrium was blocked by the intrauterine injection with anti-Slug polyclonal antibody on day 3 of pregnancy before implantation. These results suggested that up-regulation of Slug expression may play a key role in the embryo implantation in mice.