Automatic high-throughput and non-invasive selection of sperm at the biochemical level.

Background: Sperm selection, a key step in assisted reproductive technology (ART), has long been restrained at the preliminary physical level (morphology or motility); however, subsequent fertilization and embryogenesis are complicated biochemical processes. Such an enormous "gap" poses tough problems for couples dealing with infertility, especially patients with severe/total asthenozoospermia .

Methods: We developed a biochemical-level, automatic-screening/separation, smart droplet-TO-hydrogel chip (BLASTO-chip) for sperm selection.

Ultrasensitive and Quantitative DNA Methylation Detection Method Based on the MutS Protein.

DNA methylation is closely related to cancer. It is generally accepted that DNA methylation detection is crucial in cancer diagnosis, prognosis, and treatment monitoring. Therefore, there is an urgent demand for developing a simple, rapid, highly sensitive, and highly specific methylation detection method to detect DNA methylation at specific sites quantitatively.

Gaussian clustering and quantification of the sperm chromatin dispersion test using convolutional neural networks.

Sperm DNA fragmentation is a sign of sperm nuclear damage. The sperm chromatin dispersion (SCD) test is a reliable and economical method for the evaluation of DNA fragmentation. However, the cut-off value for differentiation of DNA fragmented sperms is fixed at 1/3 with limited statistical justification, making the SCD test a semi-quantitative method that gives user-dependent results.

Melatonin enhances the developmental potential of immature oocytes from older reproductive-aged women by improving mitochondrial function.

Aims: To evaluate whether melatonin (MT) supplementation during maturation (IVM) of human oocytes can reverse the age-related decline in oocyte quality.

Main Methods: We enrolled 172 patients aged ≥35 years (older reproductive-aged women) and 83 patients aged <35 years (young women) who underwent fertilization between 2019 and 2022. We conducted IVM with and without 10 μM MT in immature oocytes of different ages.

Highly-sensitive and homogenous detection of 8-oxoguanine based DNA oxidative damage by a CRISPR-enhanced structure-switching aptamer assay.

8-oxoguanine (8-oxoG) based DNA damage is the most common type of DNA damage which greatly affect gene expression. Therefore, accurate quantification of 8-oxoG based DNA damage is of high clinical significance. However, current methods for 8-oxoG detection struggle to balance convenience, low cost, and sensitivity.

A versatile and convenient tool for regulation of DNA strand displacement and post-modification on pre-fabricated DNA nanodevices.

Toehold-mediated strand displacement and its regulatory tools are fundamental for DNA nanotechnology. However, current regulatory tools all need to change the original sequence of reactants, making the regulation inconvenient and cumbersome. More importantly, the booming development of DNA nanotechnology will soon promote the production of packaged and batched devices or circuits with specified functions.

PAM-independent ultra-specific activation of CRISPR-Cas12a via sticky-end dsDNA.

Although CRISPR-Cas12a [clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 12a] combining pre-amplification technology has the advantage of high sensitivity in biosensing, its generality and specificity are insufficient, which greatly restrains its application range. Here, we discovered a new targeting substrate for LbaCas12a (Lachnospiraceae bacterium Cas12a), namely double-stranded DNA (dsDNA) with a sticky-end region (PAM-SE+ dsDNA). We discovered that CRISPR-Cas12a had special enzymatic properties for this substrate DNA, including the ability to recognize and cleave it without needing a protospacer adjacent motif (PAM) sequence and a high sensitivity to single-base mismatches in that substrate.

A sensitive and specific nano-vehicle based on self-amplified dual-input synthetic gene circuit for intracellular imaging and treatment.

Synthetic genetic circuits (SGCs) that sense multiple biomarkers and respond intelligently provide a powerful tool for intracellular biosensing. The SGC is usually loaded into the nanoscale liposomes to build functional intracellular nano-vehicles, widely applied in diagnosing and treating diseases. However, because the system needs to identify multiple targets to activate, the sensitivity will be inevitably reduced though the specificity is improved, leading to false-negative results in diagnosis and low killing dosage in treatment.

The Off-Target Effect of CRISPR-Cas12a System toward Insertions and Deletions between Target DNA and crRNA Sequences.

The CRISPR-Cas12a system is a new type of genome editing tool with high efficiency and targeting. However, other sequences in the genome may also be cleaved nonspecifically, resulting in unavoidable off-target effects. Therefore, it is necessary to learn more about the mechanism of CRISPR-Cas12a to recognize target sequences to avoid its off-target effects.

Melatonin improves the effect of cryopreservation on human oocytes by suppressing oxidative stress and maintaining the permeability of the oolemma.

Cryopreservation causes cryoinjury to oocytes and impairs their developmental competence. Melatonin (MLT) can improve the effect of cryopreservation in animal oocytes. However, no such studies on human oocytes have been reported.

Comparison of IVF and IVM outcomes in the same patient treated with a modified IVM protocol along with an oocytes-maturing system containing melatonin: A pilot study.

Aim: To compare embryonic developmental competence and clinical outcomes of oocytes matured in vivo (IVF oocytes) and those matured in vitro (IVM oocytes) from the same IVM/IVF cycles, and to analyze the clinical efficiency of a melatonin-supplemented in vitro maturation system combined with a modified IVM/IVF protocol.

Main Methods: We randomly recruited 22 patients undergoing IVM/IVF treatment protocol in our medical centre. The fertilization, cleavage and blastocyst formation rates, as well as clinical pregnancy, implantation and live birth/ongoing pregnancy rates were analysed and compared between IVF and IVM oocytes.