Chemically Conjugated Branched Staples for Super-DNA Origami.

DNA origami, comprising a long folded DNA scaffold and hundreds of linear DNA staple strands, has been developed to construct various sophisticated structures, smart devices, and drug delivery systems. However, the size and diversity of DNA origami are usually constrained by the length of DNA scaffolds themselves. Herein, we report a new paradigm of scaling up DNA origami assembly by introducing a novel branched staple concept. Owing to their covalent characteristics, the chemically conjugated branched DNA staples we describe here can be directly added to a typical DNA origami assembly system to obtain super-DNA origami with a predefined number of origami tiles in one pot. Compared with the traditional two-step coassembly system (yields <10%), a much greater yield (>80%) was achieved using this one-pot strategy. The diverse superhybrid DNA origami with the combination of different origami tiles can be also efficiently obtained by the hybrid branched staples. Furthermore, the branched staples can be successfully employed as the effective molecular glues to stabilize micrometer-scale, super-DNA origami arrays (e.g., 10 × 10 array of square origami) in high yields, paving the way to bridge the nanoscale precision of DNA origami with the micrometer-scale device engineering. This rationally developed assembly strategy for super-DNA origami based on chemically conjugated branched staples presents a new avenue for the development of multifunctional DNA origami-based materials.

Screening of Spinal Muscular Atrophy Carriers and Prenatal Diagnosis in Pregnant Women in Yancheng, China.

Spinal muscular atrophy (SMA) is a neuromuscular disorder with an autosomal recessive inheritance pattern. Patients with severe symptoms may suffer respiratory failure, leading to death. The homozygous deletion of exon 7 in the SMN1 gene accounts for nearly 95% of all cases. Population carrier screening for SMA and prenatal diagnosis by amniocentesis for high-risk couples can assist in identifying the risk of fetal disease. We provided the SMA carrier screening process to 55,447 pregnant women in Yancheng from October 2020 to December 2022. Among them, 8185 participated in this process, with a participation rate of around 14.76% (95% CI 14.47-15.06%). Quantitative real-time polymerase chain reaction (qPCR) was used to detect deletions of SMN1 exons 7 and 8 (E7, E8) in screened pregnant women. 127 were identified as carriers (111 cases of E7 and E8 heterozygous deletions, 15 cases of E7 heterozygous deletions, and 1 case of E7 heterozygous deletions and E8 homozygous deletions), resulting in a carrying rate of around 1.55% (95% CI 1.30-1.84%). After genetic counseling, 114 spouses of pregnant women who tested positive underwent SMA carrier screening; three of them were screened as SMA carriers. Multiplexed ligation-dependent probe amplification (MLPA) was used for the prenatal diagnosis of the fetuses of high-risk couples. Two of them exhibited two copies of SMN1 exon 7 (normal), and the pregnancy was continued; one exhibited no copies of SMN1 exon 7 and exon 8 (SMA patient), and the pregnancy was terminated. Analyzing SMN1 mutations in Yancheng and provide clinical evidence for SMA genetic counseling and birth defect prevention. Interventional prenatal diagnosis for high-risk families can promote informed reproductive selection and prepare for the fetus's early treatment.

Genetically Encoded DNA Origami for Gene Therapy In Vivo.

DNA origami has played an important role in various biomedical applications, including biosensing, bioimaging, and drug delivery. However, the function of the long DNA scaffold involved in DNA origami has yet to be fully exploited. Herein, we report a general strategy for the construction of a genetically encoded DNA origami by employing two complementary DNA strands of a functional gene as the DNA scaffold for gene therapy. In our design, the complementary sense and antisense strands can be directly folded into two DNA origami monomers by their corresponding staple strands. After hybridization, the assembled genetically encoded DNA origami with precisely organized lipids on the surface can function as the template for lipid growth. The lipid-coated and genetically encoded DNA origami can efficiently penetrate the cell membrane for successful gene expression. After decoration with the tumor-targeting group, the antitumor gene (p53) encoded DNA origami can elicit a pronounced upregulation of the p53 protein in tumor cells to achieve efficient tumor therapy. The targeting group-modified, lipid-coated, and genetically encoded DNA origami has mimicked the functions of cell surface ligands, cell membrane, and nucleus for communication, protection, and gene expression, respectively. This rationally developed combination of folding and coating strategies for genetically encoded DNA origami presents a new avenue for the development of gene therapy.

Circular RNA circ0001955 promotes cervical cancer tumorigenesis and metastasis via the miR-188-3p/NCAPG2 axis.

BACKGROUND: Circular RNAs (circRNAs) are known to play a crucial role in a variety of malignancies. However, the precise role of circRNAs in cervical squamous cell carcinoma (CSCC) remains largely unknown. METHODS: The expression of circ0001955 was determined by real-time quantitative PCR and fluorescence in situ hybridization. To examine the effects of circ0001955 on CSCC metastasis and growth, functional experiments were conducted in vitro and in vivo. Mechanistically, nucleocytoplasmic separation, dual luciferase reporter assay, RNA antisense purification experiments, and rescue experiments were performed to confirm the interaction between circ0001955, miR-188-3p, and NCAPG2 in CSCC. RESULTS: Here, we demonstrated that a circRNA derived from the CSNK1G1 gene (circ0001955) is significantly upregulated in CSCC. The overexpression of circ0001955 promotes tumor proliferation and metastasis, whereas the knockdown of circ0001955 exerts the opposite effects. Mechanistically, circ0001955 competitively binds miR-188-3p and prevents miR-188-3p from reducing the levels of NCAPG2, activating the AKT/mTOR signaling pathway to induce epithelial mesenchymal transformation. Notably, the application of an inhibitor of mTOR significantly antagonized circ0001955-mediated CSCC tumorigenesis. CONCLUSION: circ0001955 promotes CSCC tumorigenesis and metastasis via the miR-188-3p/NCAPG2 axis which would provide an opportunity to search new therapeutic targets for CSCC.

A DNA Origami-based Bactericide for Efficient Healing of Infected Wounds.

Bacteria infection is a significant obstacle in the clinical treatment of exposed wounds facing widespread pathogens. Herein, we report a DNA origami-based bactericide for efficient anti-infection therapy of infected wounds in vivo. In our design, abundant DNAzymes (G4/hemin) can be precisely organized on the DNA origami for controllable generation of reactive oxygen species (ROS) to break bacterial membranes. After the destruction of the membrane, broad-spectrum antibiotic levofloxacin (LEV, loaded in the DNA origami through interaction with DNA duplex) can be easily delivered into the bacteria for successful sterilization. With the incorporation of DNA aptamer targeting bacterial peptidoglycan, the DNA origami-based bactericide can achieve targeted and combined antibacterial therapy for efficiently promoting the healing of infected wounds. This tailored DNA origami-based nanoplatform provides a new strategy for the treatment of infectious diseases in vivo.

A DNA Origami-Based Gene Editing System for Efficient Gene Therapy in Vivo.

DNA nanostructures have played an important role in the development of novel drug delivery systems. Herein, we report a DNA origami-based CRISPR/Cas9 gene editing system for efficient gene therapy in vivo. In our design, a PAM-rich region precisely organized on the surface of DNA origami can easily recruit and load sgRNA/Cas9 complex by PAM-guided assembly and pre-designed DNA/RNA hybridization. After loading the sgRNA/Cas9 complex, the DNA origami can be further rolled up by the locking strands with a disulfide bond. With the incorporation of DNA aptamer and influenza hemagglutinin (HA) peptide, the cargo-loaded DNA origami can realize the targeted delivery and effective endosomal escape. After reduction by GSH, the opened DNA origami can release the sgRNA/Cas9 complex by RNase H cleavage to achieve a pronounced gene editing of a tumor-associated gene for gene therapy in vivo. This rationally developed DNA origami-based gene editing system presents a new avenue for the development of gene therapy.

Genetically Encoded Double-Stranded DNA-Based Nanostructure Folded by a Covalently Bivalent CRISPR/dCas System.

DNA nanotechnology has been widely employed in the construction of various functional nanostructures. However, most DNA nanostructures rely on hybridization between multiple single-stranded DNAs. Herein, we report a general strategy for the construction of a double-stranded DNA-ribonucleoprotein (RNP) hybrid nanostructure by folding double-stranded DNA with a covalently bivalent clustered regularly interspaced short palindromic repeats (CRISPR)/nuclease-dead CRISPR-associated protein (dCas) system. In our design, dCas9 and dCas12a can be efficiently fused together through a flexible and stimuli-responsive peptide linker. After activation by guide RNAs, the covalently bivalent dCas9-12a RNPs (staples) can precisely recognize their target sequences in the double-stranded DNA scaffold and pull them together to construct a series of double-stranded DNA-RNP hybrid nanostructures. The genetically encoded hybrid nanostructure can protect genetic information in the folded state, similar to the natural DNA-protein hybrids present in chromosomes, and elicit efficient stimuli-responsive gene transcription in the unfolded form. This rationally developed double-stranded DNA folding and unfolding strategy presents a new avenue for the development of DNA nanotechnology.

A DNA nanodevice-based vaccine for cancer immunotherapy.

A major challenge in cancer vaccine therapy is the efficient delivery of antigens and adjuvants to stimulate a controlled yet robust tumour-specific T-cell response. Here, we describe a structurally well defined DNA nanodevice vaccine generated by precisely assembling two types of molecular adjuvants and an antigen peptide within the inner cavity of a tubular DNA nanostructure that can be activated in the subcellular environment to trigger T-cell activation and cancer cytotoxicity. The integration of low pH-responsive DNA 'locking strands' outside the nanostructures enables the opening of the vaccine in lysosomes in antigen-presenting cells, exposing adjuvants and antigens to activate a strong immune response. The DNA nanodevice vaccine elicited a potent antigen-specific T-cell response, with subsequent tumour regression in mouse cancer models. Nanodevice vaccination generated long-term T-cell responses that potently protected the mice against tumour rechallenge.

Comparison between postauricular steroid injection and intratympanic steroid perfusion for refractory severe and profound sudden sensorineural hearing loss.

BACKGROUND: To analyze the clinical efficacy of intratympanic steroid perfusion (ISP) and postauricular steroid injection (PSI) for refractory severe and profound sudden sensorineural hearing loss (SSNHL). METHODS: SSNHL patients who failed a conventional treatment with severe to profound hearing loss [pure tone average (PTA, 0.25-8 kHz) > 60 dB] were treated with ISP or PSI plus antioxidant and neurotrophin for 10 consecutive days. Antioxidant and neurotrophin were administrated either intravenously and/or orally. All patients were assigned into the ISP group or the PSI group and followed up for more than three months. The changes in PTA, effective rate and side effects were analyzed in the two groups. RESULTS: Similar hearing improvements and effective rates were observed in the two groups. However, a slightly better efficacy was observed in the PSI group compared to the ISP group. Patients with shorter intervals from onset to treatment had significantly more hearing improvements. The route of antioxidant and neurotrophin administration had no impact on treatment effects. CONCLUSION: Both ISP and PSI could be used as salvage treatments for refractory SSNHL. These salvage treatments should be started as soon as possible once SSNHL patients fail a conventional treatment.

Hierarchical Assembly of Super-DNA Origami Based on a Flexible and Covalent-Bound Branched DNA Structure.

DNA origami technique provides a programmable way to construct nanostructures with arbitrary shapes. The dimension of assembled DNA origami, however, is usually limited by the length of the scaffold strand. Herein, we report a general strategy to efficiently organize multiple DNA origami tiles to form super-DNA origami using a flexible and covalent-bound branched DNA structure. In our design, the branched DNA structures (Bn: with a certain number of 2-6 branches) are synthesized by a copper-free click reaction. Equilateral triangular DNA origamis with different numbers of capture strands (Tn: T1, T2, and T3) are constructed as the coassembly tiles. After hybridization with the branched DNA structures, the super-DNA origami (up to 13 tiles) can be efficiently ordered in the predesigned patterns. Compared with traditional DNA junctions (Jn: J2-J6, as control groups) assembled by base pairing between several DNA strands, a higher yield and more compact structures are obtained using our strategy. The highly ordered and discrete DNA origamis can further precisely organize gold nanoparticles into different patterns. This rationally developed DNA origami ordering strategy based on the flexible and covalent-bound branched DNA structure presents a new avenue for the construction of sophisticated DNA architectures with larger molecular weights.

Branched Antisense and siRNA Co-Assembled Nanoplatform for Combined Gene Silencing and Tumor Therapy.

Chemically modified DNA has been widely developed to fabricate various nucleic acid nanostructures for biomedical applications. Herein, we report a facile strategy for construction of branched antisense DNA and small interfering RNA (siRNA) co-assembled nanoplatform for combined gene silencing in vitro and in vivo. In our design, the branched antisense can efficiently capture siRNA with 3' overhangs through DNA-RNA hybridization. After being equipped with an active targeting group and an endosomal escape peptide by host-guest interaction, the tailored nucleic acid nanostructure functions efficiently as both delivery carrier and therapeutic cargo, which is released by endogenous RNase H digestion. The multifunctional nucleic acid nanosystem elicits an efficient inhibition of tumor growth based on the combined gene silencing of the tumor-associated gene polo-like kinase 1 (PLK1). This biocompatible nucleic acid nanoplatform presents a new strategy for the development of gene therapy.

Hypoxia: involved but not essential for endometrial breakdown in mouse menstural-like model.

Menstruation is a specific physiological phenomenon that occurs in women. However, molecular mechanisms underlying this phenomenon are still unclear. According to the classical theory, tissue hypoxia resulting from vasoconstriction of the spiral arteries after progesterone (P4) withdrawal initiates the breakdown of the endometrium at the earliest stage of menstruation. However, this theory has been challenged by previous studies that have questioned the function and even the existence of hypoxia during menstruation. In this study, we not only provide convincing evidence that hypoxia exists during endometrial breakdown, but also further explore the role of hypoxia and hypoxia-inducible factor 1 (HIF1) in this process. Based on mouse menstrual-like model and experiments with human decidual stromal cells, we observed that P4 withdrawal induced both hypoxia and HIF1 activation; however, endometrial breakdown was triggered only by P4 withdrawal. Hypoxia significantly enhanced the mRNA expression of specific matrix metalloproteinases (MMPs) under the conditions of P4 withdrawal. In conclusion, hypoxia is involved but not an essential component of endometrial breakdown during menstruation.

Upregulation of miR-205 induces CHN1 expression, which is associated with the aggressive behaviour of cervical cancer cells and correlated with lymph node metastasis.

BACKGROUND: Cervical cancer is the leading cause of cancer-related death in women worldwide. However, the mechanisms mediating the development and progression of cervical cancer are unclear. In this study, we aimed to elucidate the roles of microRNAs and a1-chimaerin (CHN1) protein in cervical cancer progression. METHODS: The expression of miR-205 and CHN1 protein was investigated by in situ hybridisation and immunohistochemistry. We predicted the target genes of miR-205 using software prediction and dual luciferase assays. The expression of mRNAs and proteins was tested by qRT-PCR and western blotting respectively. The ability of cell growth, migration and invasion was evaluated by CCK-8 and transwell. Cell apoptosis was analysed by flow cytometry analysis. RESULTS: We found that miR-205 and CHN1 were highly expressed in human cervical cancer tissue compared with paired normal cervical tissues. The CHN1 gene was shown to be targeted by miR-205 in HeLa cells. Interestingly, transfection with miR-205 mimic upregulated CHN1 mRNA and protein, while miR-205 inhibitor downregulated CHN1 in high-risk and human papilloma virus (HPV)-negative human cervical cancer cells in vitro,. These data suggested that miR-205 positively regulated the expression of CHN1. Furthermore, the miR-205 mimic promoted cell growth, apoptosis, migration, and invasion in high-risk and HPV-negative cervical cancer cells, while the miR-205 inhibitor blocked these biological processes. Knockdown of CHN1 obviously reduced the aggressive cellular behaviours induced by upregulation of miR-205, suggesting that miR-205 positively regulated CHN1 to mediate these cell behaviours during the development of cervical cancer. Furthermore, CHN1 was correlated with lymph node metastasis in clinical specimens. CONCLUSIONS: Our findings showed that miR-205 positively regulated CHN1 to mediate cell growth, apoptosis, migration, and invasion during cervical cancer development, particularly for high-risk HPV-type cervical cancer. These findings suggested that dysregulation of miR-205 and subsequent abnormalities in CHN1 expression promoted the oncogenic potential of human cervical cancer.

Spatiotemporal pattern analysis of schistosomiasis based on village level in the transmission control stage in lake and marshland areas in China.

Hubei Province is one of the endemic regions with severe schistosomiasis in China. To eliminate schistosomiasis in lake and marshland regions, this study detected hotspots of schistosomiasis cases both spatially and spatiotemporally on the basis of spatial autocorrelation; clustering and outlier, purely spatial and spatiotemporal cluster analyses at the village level from 2013 to 2017 in Hubei Province. The number of cases confirmed positive by an immunodiagnostic test and etiological diagnosis and advanced schistosomiasis cases dramatically declined during the study period. Significant global spatial autocorrelation of schistosomiasis patients was found at the village level in the whole province in 5 years. Clustering and outlier analysis showed that most HH villages were mainly concentrated along the Yangtze River, especially in Jianghan Plain. Spatial and spatiotemporal cluster analyses showed that significant clusters of the schistosomiasis cases were detected at the village level. In general, space and spatiotemporal clustering of schistosomiasis cases at the village level demonstrated a downward trend from 2013 from 2017 in Hubei Province. High-risk regions included Jianghan Plain along the middle reach of Yangtze River and Yangxin County in the lower reaches of the Yangtze River in Hubei Province. To eliminate schistosomiasis, precise control and management of schistosomiasis cases should be strictly implemented. Moreover, comprehensive prevention and control measures should be continuously strengthened in these regions.

High false-positive non-invasive prenatal screening results for sex chromosome abnormalities: Are maternal factors the culprit?

OBJECTIVE: To explore the impact of maternal sex chromosome aneuploidies (SCAs) and copy number variation (CNV) on false-positive results of non-invasive prenatal screening (NIPS) for predicting foetal SCAs. METHODS: In total, 22 844 pregnant women were recruited to undergo NIPS. Pregnant women with high-risk of SCAs underwent prenatal diagnosis and maternal copy number variation sequencing (CNV-seq). RESULTS: Among 117 women with high-risk of SCAs, 72 accepted prenatal diagnosis, 86 accepted maternal CNV-seq, and 21 had maternal sex chromosome abnormalities. The abnormality rate was significantly higher than women at low-risk of SCAs (24.42% vs 3.51%). Using a novel parameter cffDNA (ChrX)/cffDNA, when the ratio was greater than 2, all foetuses had normal karyotype, and 75.0% (6/8) had abnormal maternal chromosome X. If the ratio was less than or equal to 2, only 10% (4/40) of the mothers had chromosome X CNV alterations, while 33.3% (13/40) of their foetuses had sex chromosomes CNV abnormalities. CONCLUSIONS: Approximately 25% of pregnant women with SCAs predicted by NIPS had sex chromosome abnormalities as determined by CNV-seq. The ratio of cffDNA (ChrX)/cffDNA can tentatively distinguish the maternal or foetal origin of abnormal cell-free DNA. In a reanalysis of previous NIPS data, false-positive results caused by maternal CNV might be elucidated.

[Prenatal diagnosis and pedigree analysis of a case of Nail-patella syndrome].

OBJECTIVE: To carried out prenatal diagnosis and genetic analysis for a case with Nail-patella syndrome. METHODS: Based on the clinical phenotype and prenatal imaging, genetic testing and prenatal diagnosis were carried out through whole exome sequencing (WES) and Sanger sequencing. RESULTS: Analysis of amniotic fluid showed that the fetus has carried a heterozygous c.139+1G>T splicing site variant [Chr9(GRCh37): g.129376868G>T] of the LMX1B gene, which was verified by Sanger sequencing. The same heterozygous variant was found in the pregnant woman, her daughter and her mother but not in her husband. Searching of HGMD database showed that the c.139+1G>T was previously unreported. CONCLUSION: Nail-patella syndrome is an autosomal dominant genetic disorder with various clinical manifestations. WES is helpful for its genetic and prenatal diagnosis.

[Influence of maternal chromosomal abnormalities on non-invasive prenatal testing for fetal sex chromosome aneuploidies].

OBJECTIVE: To study the influence of maternal sex chromosomal abnormalities on the prediction of fetal sex chromosome abnormalities (SCAs) by non-invasive prenatal testing (NIPT). METHODS: Thirty-six pregnant women with a prediction for fetal SCAs by NIPT were verified as false positive after prenatal diagnosis using amniotic fluid samples. With informed consent, these women were subjected to chromosomal karyotyping or copy number variations (CNVs) analysis through high-throughput sequencing. RESULTS: Sex chromosomal abnormalities were found in 8 women, which yielded an abnormal rate of 22.22% (8/36). Among these, 3 had sex chromosome aneuploidies (47, XXX), 4 had sex chromosome mosaicisms, and 1 carried structural chromosomal abnormalities. Reanalysis of the results of NIPT were consistent with the maternal CNVs by large. With the ratio of cffDNA (ChrX)/cffDNA was more than 2, 6 of the eight women were found to harbor sex chromosome abnormalities, and the fetal karyotype was normal. However, with a ratio of less than 2, only 2 of the 38 pregnant women had sex chromosome abnormalities, and 10 of the fetuses were confirmed as positive. CONCLUSION: The presence of maternal sex chromosomal abnormalities can greatly influence the result of NIPT, which may also be an important reason for false prediction for fetal SCAs by NIPT. When NIPT indicates abnormal SCAs, it is necessary to analyze maternal sex chromosomes. The ratio of cffDNA(ChrX)/cffDNA may help to determine the source of abnormal signals.

[Prenatal diagnosis of two cases with 2p15-p16.1 microdeletion syndrome].

OBJECTIVE: To detect chromosomal aberrations in two fetuses with multiple malformation. METHODS: The two fetuses were subjected to chromosomal microarray analysis (CMA) by using Affymetrix CytoScan 750K arrays. The results were analyzed by bioinformatic software. RESULTS: CMA analysis suggested that both fetuses harbored pathogenic copy number variations (CNVs) in the 2p15-16.1 region, which ranged from 255 kb to 257 kb and encompassed the XPO1 and USP34 genes. CONCLUSION: Deletion of the chr2 (61 659 957-61 733 075, hg19) encompassing the XPO1 and USP34 genes may underlie the multiple malformations in the two fetuses.

[Fetal malnutrition assessment program].

OBJECTIVE: To study the application of ponderal index (PI), body mass index (BMI), mid-arm circumference/head circumference (MAC/HC), and Clinical Assessment of Nutritional Status (CANS) score in assessing the nutritional status of neonates at birth, and to find a simple and reliable scheme for the assessment of fetal nutritional status. METHODS: PI, BMI, MAC/HC, and CANS were used to assess the nutritional status of full-term infants and preterm infants shortly after birth. The assessment results of these methods were analyzed. RESULTS: Among the 678 full-term infants, 61, 102, 47, and 131 were diagnosed with malnutrition by PI, BMI, MAC/HC, and CANS respectively. Among the 140 preterm infants, 30, 87, 9, and 112 were diagnosed with malnutrition by PI, BMI, MAC/HC, and CANS respectively. The combination of BMI and CANS had a detection rate of 99.3% in full-term infants and 100% in preterm infants. Compared with the single method, the combination significantly improved the detection rate of malnutrition (P < 0.05), while there was no significant difference between the combination of BMI+CANS and the combination of PI+BMI+CANS (P > 0.05). CONCLUSIONS: The combination of BMI+CANS can reduce the rate of missed diagnosis of fetal malnutrition. It is therefore a simple and reliable method for the assessment of fetal malnutrition.

A Self-Assembled Platform Based on Branched DNA for sgRNA/Cas9/Antisense Delivery.

Precisely assembled DNA nanostructures are promising candidates for the delivery of biomolecule-based therapeutics. Herein, we introduce a facile strategy for the construction of a branched DNA-based nanoplatform for codelivery of gene editing (sgRNA/Cas9, targeting DNA in the nucleus) and gene silencing (antisense, targeting mRNA in the cytoplasm) components for synergistic tumor therapy in vitro and in vivo. In our design, the branched DNA structure can efficiently load a sgRNA/Cas9/antisense complex targeting a tumor-associated gene, PLK1, through DNA self-assembly. With the incorporation of an active targeting aptamer and an endosomal escape peptide by host-guest interaction, the biocompatible DNA nanoplatform demonstrates efficient inhibition of tumor growth without apparent systemic toxicity. This multifunctional DNA nanocarrier provides a new strategy for the development of gene therapeutics.