Publications by authors named "Dalei Yang"

6 Publications

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An effective method for trophectoderm biopsy using mechanical blunt dissection: a step-by-step demonstration.

Fertil Steril 2020 08 9;114(2):438-439. Epub 2020 Jul 9.

Center of Reproductive Medicine, Shengjing Hospital of China Medical University, Shenyang, People's Republic of China. Electronic address:

Objective: To present an effective approach to trophectoderm biopsy for blastocysts of different stages and characteristics by mechanical blunt dissection (MBD).

Design: Stepwise demonstration with still pictures and operational video clips to explain tips and tricks for trophectoderm biopsy. (This demonstration was approved by the Reproductive Study Ethics Committee at Shengjing Hospital of China Medical University.) SETTING: In vitro fertilization laboratory.

Patient(s): Patients who underwent preimplantation genetic testing.

Intervention(s): The illustrated techniques of blastocyst trophectoderm biopsy using micromanipulation methods include artificial shrinkage, zona pellucida drilling, injecting media from the drilling, aspiration of trophectoderm cells into the biopsy pipette (outer diameter 27 μm for fully expanded blastocysts and peanut-shaped hatching blastocysts; outer diameter 20 μm for 8-shaped hatching and hatched blastocysts), detachment of the trophectoderm cells by laser pulse combined with MBD (performed using the rims of the biopsy and holding pipettes), and release of the biopsy fragment.

Main Outcome Measure(s): Successful biopsy rate and survival after warming.

Result(s): Our biopsy strategy does not involve assisted hatching on day-3 or day-4 embryos, which can leave the embryo undisturbed in culture up to the expanded blastocyst stage. Notably, this approach demonstrates several noteworthy advantages for sampling blastocysts of different stages and characteristics, and it maintains a desirable successful biopsy rate (95.4%, n = 1,872) and survival rate after warming (100%, n = 440). The MBD method may reduce thermal damage because fewer laser pulses are used, compared with the traditional laser-only biopsy techniques. For noncollapsed blastocysts after artificial shrinkage, the strategy of injecting medium from the zona pellucida drilling helps to separate the trophectoderm cells from the zona pellucida, thus facilitating the biopsy procedure. For peanut-shaped hatching blastocysts, this approach could provide better control over the aspiration of trophectoderm cells into the biopsy pipette. Especially if the inner cell mass is herniating from the zona pellucida, the trophectoderm biopsy can be performed away from the inner cell mass to avoid damaging it. In addition, the MBD approach combined with the biopsy pipette (outer diameter 20 μm) can effectively control the target number of trophectoderm cells, thus simplifying the process of obtaining a biopsy from a hatched blastocyst.

Conclusion(s): Our biopsy approach demonstrates several noteworthy advantages. Considering its benefits and the simplicity of its execution, this systematic biopsy method for blastocysts of different stages and characteristic can be widely applied.
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August 2020

Minimally invasive preimplantation genetic testing using blastocyst culture medium.

Hum Reprod 2019 07;34(7):1369-1379

Center of Reproductive Medicine, Shengjing Hospital of China Medical University, Huaxiang Road, Shenyang, China.

Study Question: Is minimally invasive chromosome screening (MICS) using blastocyst culture medium (BCM) sufficiently fast and accurate for preimplantation genetic testing (PGT).

Summary Answer: A new assay for MICS, named MICS-Inst achieved high-resolution, comprehensive chromosome ploidy detection using BCM.

What Is Known Already: BCM is a viable source of genomic DNA for use in PGT.

Study Design, Size, Duration: Forty-one vitrified blastocysts donated by 22 couples known to carry a chromosome rearrangement and 21 vitrified blastocysts donated from 8 couples with normal karyotypes were used in this study. Good-quality blastocysts, defined as Day 5 and Day 6 embryos ≥ BB (AA, AB, BA, BB) based on the Gardner system were used for analysis. Recruitment took place from May 2018 to August 2018. We performed PGT for structural rearrangements (PGT-SR) on 41 BCM, trophectoderm (TE) biopsy and blastocyst-stage embryo (BE) samples as well as PGT for aneuploidies (PGT-A) on 21 BCM, TE biopsy and BE samples.

Participants/materials, Setting, Methods: We made several significant modifications to the BCM composition (mixing blastocoel fluid and spent blastocyst medium) as well as the pre-existing multiple annealing and looping-based amplification cycles (MALBAC) techniques and library generation procedures. The design of a quasilinear preamplification (Pre-AMP) primer and AMP primers 1 and 2 enables the preparation of a next-generation sequencing library after the exponential amplification stage by introducing the Illumina P5 and P7 primers into the final products, which are then ready for sequencing. Sequencing was performed on the Illumina Hiseq 2500 platform with 2.0 Mb raw reads generated for each sample.

Main Results And The Role Of Chance: For PGT-A, BCM and TE biopsy samples showed 90% and 86% clinical concordance with the corresponding BE samples, respectively. In addition, both BCM and TE biopsy samples showed 76% karyotype concordance with the corresponding BE samples. For PGT-SR, we successfully obtained ploidy information for all 23 chromosomes with the exception of any rearrangements involving the Y chromosome. Both BCM and TE biopsy samples showed 100% clinical concordance with the corresponding BE samples in detecting chromosomal rearrangements. BCM and TE biopsy samples showed 90% and 100% karyotype concordance with the corresponding BE samples, respectively. Additionally, no statistically significant differences were detected in the aforementioned values of the BCM and TE biopsy samples in either PGT-A or PGT-SR (P > 0.05). Moreover, we achieved accurate quantification of segmental abnormalities using BCM samples. In addition, MICS-Inst reduced the number of steps required for library preparation through the use of new primer designs, resulting in an overall time reduction of 7.5 h. This time reduction allows for the performance of fresh blastocyst transfers.

Limitations, Reasons For Caution: The main limitation is that BE, rather the inner cell mass, was used as the standard to evaluate the chromosome screening results.

Wider Implications Of The Findings: These results show that MICS-Inst is effective in procedure and precision for PGT, and that it is possible to achieve fresh blastocyst transfer following PGT. The implications are significant, as these findings may lead to minimally invasive PGT methods in the future.

Study Funding/competing Interest(s): This work was supported by the National Natural Science Foundation of China (No. 81671423 and No. 81402130), the National Key Research and Development Program of China (No. 2018YFC1003100), Liaoning Provincial Key Research and Development Program (No. 2018225090), the Fok Ying Tung Education Foundation (No. 151039) and Distinguished Talent Program of Shengjing Hospital (No. ME76). No competing interests declared.
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July 2019

High-Performance Additive-/Post-Treatment-Free Nonfullerene Polymer Solar Cells via Tuning Molecular Weight of Conjugated Polymers.

Small 2018 Apr 23;14(16):e1704491. Epub 2018 Mar 23.

State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Renmin Str. 5625, Changchun, 130022, P. R. China.

In recent years, rapid advances are achieved in polymer solar cells (PSCs) using nonfullerene small molecular acceptors. However, no research disclosing the influence of molecular weight (M ) of conjugated polymer on the nonfullerene device performance is reported. In this work, a series of polymers with different M s are synthesized to systematically investigate the connection between M and performance of nonfullerene devices for the first time. It is found that the device performance improves substantially as the M increases from 12 to 38 kDa and a power conversion efficiency (PCE) as high as 10.5% is realized. It has to be noted this PCE is achieved without using any additives and post-treatments, which is among the top efficiencies of additive- and post-treatment-free PSCs. Most importantly, the variation trend of the optimal active layer thickness and morphology is significantly different from the device with fullerene as acceptor. The findings clarify the effect of M on the performance of nonfullerene PSCs, which would benefit further efficiency improvement of nonfullerene PSCs.
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April 2018

Side-Chain Engineering for Enhancing the Thermal Stability of Polymer Solar Cells.

Adv Mater 2015 Nov 1;27(43):6999-7003. Epub 2015 Oct 1.

State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, 130022, P. R. China.

An effective strategy of engineering side chains is proposed for enhancing solar-cell-device thermal stability. As the conjugated length of the side chains increases, the morphological stability of the blend film is enhanced. The thermal stability of corresponding devices is consequently improved.
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November 2015

A novel biomarker ARMc8 promotes the malignant progression of ovarian cancer.

Hum Pathol 2015 Oct 16;46(10):1471-9. Epub 2015 Jun 16.

Department of Pathology, First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, China, 110001. Electronic address:

Ovarian cancer is the most lethal gynecologic malignancy worldwide, and the survival rates have remained low in spite of medical advancements. More research is dedicated to the identification of novel biomarkers for this deadly disease. The association between ARMc8 and ovarian cancer remained unraveled. In this study, immunohistochemical staining was used to examine ARMc8 expression in 247 cases of ovarian cancer, 19 cases of borderline ovarian tumors, 41 cases of benign ovarian tumors, and 9 cases of normal ovarian tissues. It was shown that ARMc8 was predominantly located in the cytoplasm of tumor cells, and its expression was up-regulated in the ovarian cancer (61.9%) and the borderline ovarian tumor tissues (57.9%), in comparison with the benign ovarian tumors (12.2%; P < .05) and the normal ovarian tissues (11.1%; P < .05). In ovarian cancer, ARMc8 expression was closely related to International Federation of Gynecology and Obstetrics stages (P = .002), histology grade (P < .001), lymph node metastasis (P = .008), and poor prognosis (P < .001). Univariate and multivariate Cox analyses revealed that ARMc8 expression was an independent prognostic factor for ovarian cancer (P = .039 and P = .005). In addition, ARMc8 could promote the invasion and migration of ovarian cancer cells. Overexpressing ARMc8 enhanced the invasion and metastasis capacity of ARMc8-low Cavo-3 cells (P < .001), whereas interfering ARMc8 significantly reduced cell invasion and metastasis in ARMc8-high SK-OV-3 cells (P < .001). Furthermore, ARMc8 could up-regulate matrix metalloproteinase-7 and snail and down-regulate α-catenin, p120ctn, and E-cadherin. Collectively, ARMc8 may enhance the invasion and metastasis of ovarian cancer cells and likely to become a potential therapeutic target for ovarian cancer.
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October 2015

Selective, highly sensitive fluorescent probe for the detection of sulfur dioxide derivatives in aqueous and biological environments.

Anal Chem 2015 Jan 8;87(1):609-16. Epub 2014 Dec 8.

College of Chemistry and Chemical Engineering, Central South University , Changsha, Hunan Province 410083, P. R. China.

On the basis of a unique nucleophilic addition reaction, a novel water-soluble broadly emitting (500-700 nm) fluorescent Probe 1 was developed for the rapid detection of SO2 derivatives in aqueous media. The positively-charged benzopyrylium moiety in Probe 1 provides both excellent water solubility, making this probe applicable in 100% aqueous environments, and the ability to function as a fluorescence quencher of the coumarin moiety. Probe 1 generates a nearly instantaneous strong fluorescence signal in response to SO2 derivatives having an 8.3 nM detection limit for bisufite. The resulting Probe 1-sulfite adduct emits in the green/red spectral region (λ(max) = 585 nm) with a large Stokes shift (139 nm). The probe exhibits excellent selectivity toward SO2 derivatives over other potential interfering agents including reactive sulfur-containing species. Importantly, we demonstrate that Probe 1 can be used for the real-time sensing and bioimaging of SO2 derivatives in living cells.
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January 2015