First-trimester noninvasive prenatal diagnosis of seven facioscapulohumeral muscular dystrophy type 1 families using SNP-based amplicon sequencing: An earlier, rapid and safer way

The study is to explore the feasibility and value of SNP-based noninvasive prenatal diagnosis (NIPD) for facioscapulohumeral muscular dystrophy type 1 (FSHD1) in early pregnancy weeks. We prospectively collected seven FSHD1 families, with an average gestational age of 8+6. Among these seven couples, there were three affected FSHD1 mothers and four affected fathers. A multiplex-PCR panel comprising 402 amplicons was designed to selective enrich for highly heterozygous SNPs upstream of the DUX4 gene. Risk haplotype was constructed based on familial linkage analysis. Fetal genotypes were accurately inferred through relative haplotype dosage analysis using Bayes Factor. All tests were successfully completed in a single attempt, and no recombination events were detected. NIPD results were provided within a week, which is 4 weeks earlier than karyomapping and 7 weeks earlier than Bionano single-molecule optical mapping (BOM). Ultimately, five FSHD1 fetuses and two normal fetuses were successfully identified, with a 100% concordance rate with karyomapping and BOM. Therefore, SNP-based NIPD for FSHD1 was demonstrated to be feasible and accurate in early weeks of gestation, although the risk of recombination events cannot be completely eliminated. In the future, testing of more cases is still necessary to fully determine the clinical utility.

Facile synthesis of manganese-hafnium nanocomposites for multimodal MRI/CT imaging and in vitro photodynamic therapy of colon cancer

Precise diagnosis of complex and soft tumors is challenging, which limits appropriate treatment options to achieve desired therapeutic outcomes. However, multifunctional nano-sized contrast enhancement agents based on nanoparticles improve the diagnosis accuracy of various diseases such as cancer. Herein, a facile manganese-hafnium nanocomposites (Mn3O4-HfO2 NCs) system was designed for bimodal magnetic resonance imaging (MRI)/computed tomography (CT) contrast enhancement with a complimentary function of photodynamic therapy. The solvothermal method was used to fabricate NCs, and the average size of Mn3O4 NPs and Mn3O4-HfO2 NCs was about 7 nm and 15 nm, respectively, as estimated by TEM. Dynamic light scattering results showed good dispersion and high negative (-33 eV) zeta potential, indicating excellent stability in an aqueous medium. Mn3O4-HfO2 NCs revealed negligible toxic effects on the NCTC clone 929 (L929) and mouse colon cancer cell line (CT26), demonstrating promising biocompatibility. The synthesized Mn3O4-HfO2 NCs exhibit significant enhancement in T1-weighted magnetic resonance imaging (MRI) and X-ray computed tomography (CT), indicating the appropriateness for dual-modal MRI/CT molecular imaging probes. Moreover, ultra-small Mn3O4-HfO2 NCs show good relaxivities for MRI/CT. These nanoprobes Mn3O4-HfO2 NCs further possessed outstanding reactive oxygen species (ROS) generation ability under minute ultraviolet light (6 mW·cm-2) to ablate the colon cancer cells in vitro. Therefore, the designed multifunctional Mn3O4-HfO2 NCs were ideal candidates for cancer diagnosis and photodynamic therapy.

Noninvasive twin genotyping for recessive monogenic disorders by relative haplotype dosage

OBJECTIVE

To establish a haplotype-based noninvasive prenatal testing (NIPT) workflow for single-gene recessive disorders that adapt to dizygotic (DZ) twin pregnancies.

METHOD

Twin pregnancies at risk of Duchenne muscular dystrophy, Becker muscular dystrophy, hemophilia B, spinal muscular atrophy, phenylketonuria, and nonsyndromic hearing loss were recruited. For subsequent analysis, capture sequencing targeting highly heterozygotic single nucleotide polymorphism sites was conducted. Paternal-specific alleles were used to calculate the total and individual fetal fractions and determine zygosity. A two-step Bayes Factor model was applied to clarify the complex genomic landscape in the maternal plasma: the first step involved determining whether the twins inherited the same haplotype, and the second step involved estimating their individual genotypes. NIPT results were subsequently confirmed by invasive diagnosis.

RESULTS

Nine twin pregnancies were recruited, including five DZ and four monozygotic (MZ) twins. The earliest gestational age was 8+0 weeks, and the minimum fetal fraction was 4.6%. Three twin pregnancies were reported with one affected fetus, while the remaining six were reported without affected fetuses. Two dichorionic diamniotic twin pregnancies were confirmed to be MZ twins. The NIPT results were 100% consistent with those of invasive procedures or diagnostic genetic testing after birth.

CONCLUSION

This study is the first to perform NIPT for single-gene disorders in twin pregnancies and preliminarily confirm its clinical feasibility. Acknowledging the twins' genotypes in the first trimester is valuable as it empowers obstetric care providers and parents to have adequate time for pregnancy management and decision-making.

Genetic analysis of 37 cases with primary periodic paralysis in Chinese patients

BACKGROUND

Primary periodic paralysis (PPP) is an inherited disorders of ion channel dysfunction characterized by recurrent episodes of flaccid muscle weakness, which can classified as hypokalemic (HypoPP), normokalemic (NormoPP), or hyperkalemic (HyperPP) according to the potassium level during the paralytic attacks. However, PPP is charactered by remarkable clinical and genetic heterogeneity, and the diagnosis of suspected patients is based on the characteristic clinical presentation then confirmed by genetic testing. At present, there are only limited cohort studies on PPP in the Chinese population.

RESULTS

We included 37 patients with a clinical diagnosis of PPP. Eleven (29.7%) patients were tested using a specific gene panel and 26 (70.3%) by the whole-exome sequencing (WES). Twenty-two cases had a genetic variant identified, representing a diagnostic rate of 59.5% (22/37). All the identified mutations were either in the SCN4A or the CACNA1S gene. The overall detection rate was comparable between the panel (54.5%: 6/11) and WES (61.5%: 16/26). The remaining patients unresolved through panel sequencing were further analyzed by WES, without the detection of any mutation. The novel atypical splicing variant c.2020-5G > A affects the normal splicing of the SCN4A mRNA, which was confirmed by minigene splicing assay. Among 21 patients with HypoPP, 15 patients were classified as HypoPP-2 with SCN4A variants, and 6 HypoPP-1 patients had CACNA1S variants.

CONCLUSIONS

Our results suggest that SCN4A alleles are the main cause in our cohort, with the remainder caused by CACNA1S alleles, which are the predominant cause in Europe and the United States. Additionally, this study identified 3 novel SCN4A and 2 novel CACNA1S variants, broadening the mutation spectrum of genes associated with PPP.

Dumbbell-shaped bimetallic AuPd nanoenzymes for NIR-II cascade catalysis-photothermal synergistic therapy

The noble metal NPs that are currently applied to photothermal therapy (PTT) have their photoexcitation location mainly in the NIR-I range, and the low tissue penetration limits their therapeutic effect. The complexity of the tumor microenvironment (TME) makes it difficult to inhibit tumor growth completely with a single therapy. Although TME has a high level of H2O2, the intratumor H2O2 content is still insufficient to catalyze the generation of sufficient hydroxide radicals (‧OH) to achieve satisfactory therapeutic effects. The AuPd-GOx-HA (APGH) was obtained from AuPd bimetallic nanodumbbells modified by glucose oxidase (GOx) and hyaluronic acid (HA) for photothermal enhancement of tumor starvation and cascade catalytic therapy in the NIR-II region. The CAT-like activity of AuPd alleviates tumor hypoxia by catalyzing the decomposition of H2O2 into O2. The GOx-mediated intratumoral glucose oxidation on the one hand can block the supply of energy and nutrients essential for tumor growth, leading to tumor starvation. On the other hand, the generated H2O2 can continuously supply local O2, which also exacerbates glucose depletion. The peroxidase-like activity of bimetallic AuPd can catalyze the production of toxic ‧OH radicals from H2O2, enabling cascade catalytic therapy. In addition, the high photothermal conversion efficiency (η = 50.7 %) of APGH nanosystems offers the possibility of photothermal imaging-guided photothermal therapy. The results of cell and animal experiments verified that APGH has good biosafety, tumor targeting, and anticancer effects, and is a precious metal nanotherapeutic system integrating glucose starvation therapy, nano enzyme cascade catalytic therapy, and PTT therapy. This study provides a strategy for photothermal-cascade catalytic synergistic therapy combining both exogenous and endogenous processes. STATEMENT OF SIGNIFICANCE: AuPd-GOx-HA cascade nanoenzymes were prepared as a potent cascade catalytic therapeutic agent, which enhanced glucose depletion, exacerbated tumor starvation and promoted cancer cell apoptosis by increasing ROS production through APGH-like POD activity. The designed system has promising photothermal conversion ability in the NIR-II region, simultaneously realizing photothermal-enhanced catalysis, PTT, and catalysis/PTT synergistic therapy both in vitro and in vivo. The present work provides an approach for designing and developing catalytic-photothermal therapies based on bimetallic nanoenzymatic cascades.

Experimental Demonstration of Topological Catalysis for CO2 Electroreduction

The past decade has witnessed substantial progress in understanding nontrivial band topology and discovering exotic topological materials in condensed-matter physics. Recently, topological physics has been further extended to the chemistry discipline, leading to the emergence of topological catalysis. In principle, the topological effect is detectable in catalytic reactions, but no conclusive evidence has been reported yet. Herein, by precisely manipulating the topological surface state (TSS) of Bi2Se3 nanosheets through thickness control and the application of a magnetic field, we provide direct experimental evidence to illustrate topological catalysis for CO2 electroreduction. With and without the cooperation of TSS, CO2 is mainly reduced into liquid fuels (HCOOH and H2C2O4) and CO, exhibiting high (up to 90% at -1.1 V versus reversible hydrogen electrode) and low Faradaic efficiency (FE), respectively. Theoretically, the product and FE difference can be attributed to the TSS-regulated adsorption of key intermediates and the reduced barrier of the potential-determining step. Our work demonstrates the inherent correlation between band topology and electrocatalysis, paving a new avenue for designing high-performance catalysts.

[Analysis of a child with Microvillus inclusion disease due to variants of MYO5B gene and a literature review]

OBJECTIVE

To explore the clinical and genetic characteristics of a neonate with Microvillus inclusion disease (MVID).

METHODS

A neonate with MVID admitted to the First Affiliated Hospital of Zhengzhou University in May 2019 was selected as the study subject. Clinical data were collected. Whole exome sequencing (WES) was carried out, and candidate variants were verified by Sanger sequencing and multiple ligation-dependent probe amplification (MLPA). A literature was also carried out to summarize the clinical and genetic characteristics of MVID.

RESULTS

The prematurely born neonate had presented with unexplained refractory diarrhea and metabolic acidosis. Active symptomatic treatment was ineffective, and the child had died at 2 months old. WES revealed that he had harbored compound heterozygous variants of the MYO5B gene, namely c.1591C>T (p.R531W) and deletion of exon 9. Sanger sequencing showed that the R531W variant was inherited form his father, and MLPA confirmed that the exon 9 deletion was inherited from his mother. Seven children with MVID were reported in China, of which one was lost during follow-up and six had deceased. One hundred eighty eight patients were reported worldwide and only one was cured. The clinical features of MVID had included refractory diarrhea, metabolic acidosis and poor prognosis.

CONCLUSION

The child was diagnosed with MVID due to the compound heterozygous variants of the MYO5B gene, which has provided a basis for genetic counseling and prenatal diagnosis.

Spike structure of gold nanobranches induces hepatotoxicity in mouse hepatocyte organoid models

BACKGROUND

Gold nanoparticles (GNPs) have been extensively recognized as an active candidate for a large variety of biomedical applications. However, the clinical conversion of specific types of GNPs has been hindered due to their potential liver toxicity. The origin of their hepatotoxicity and the underlying key factors are still ambiguous. Because the size, shape, and surfactant of GNPs all affect their properties and cytotoxicity. An effective and sensitive platform that can provide deep insights into the cause of GNPs' hepatotoxicity in vitro is therefore highly desired.

METHODS

Here, hepatocyte organoid models (Hep-orgs) were constructed to evaluate the shape-dependent hepatotoxicity of GNPs. Two types of GNPs with different nanomorphology, gold nanospheres (GNSs) and spiny gold nanobranches (GNBs), were synthesized as the representative samples. Their shape-dependent effects on mice Hep-orgs' morphology, cellular cytoskeletal structure, mitochondrial structure, oxidative stress, and metabolism were carefully investigated.

RESULTS

The results showed that GNBs with higher spikiness and tip curvature exhibited more significant cytotoxicity compared to the rounded GNSs. The spike structure of GNBs leads to a mitochondrial damage, oxidative stress, and metabolic disorder in Hep-orgs. Meanwhile, similar trends can be observed in HepG2 cells and mice models, demonstrating the reliability of the Hep-orgs.

CONCLUSIONS

Hep-orgs can serve as an effective platform for exploring the interactions between GNPs and liver cells in a 3D perspective, filling the gap between 2D cell models and animal models. This work further revealed that organoids can be used as an indispensable tool to rapidly screen and explore the toxic mechanism of nanomaterials before considering their biomedical functionalities.

High Thermal Conductivity and Radiative Cooling Designed Boron Nitride Nanosheets/Silk Fibroin Films for Personal Thermal Management

The implementation of passive cooling strategies is crucial for transitioning from the current high-power- and energy-intensive thermal management practices to more environmentally friendly and carbon-neutral alternatives. Among the various approaches, developing thermal management materials with high thermal conductivity and emissivity for effective cooling of personal and wearable devices in both indoor and outdoor settings poses significant challenges. In this study, we successfully fabricated a cooling patch by combining biodegradable silk fibroin with boron nitride nanosheets. This patch exhibits consistent heat dissipation capabilities under different ambient conditions. Leveraging its excellent radiative cooling efficiency (Rsolar = 0.89 and εLWIR = 0.84) and high thermal conductivity (in-plane 27.58 W m-1 K-1 and out-plane 1.77 W m-1 K-1), the cooling patch achieves significant simulated skin temperature reductions of approximately 2.5 and 8.2 °C in outdoor and indoor conditions, respectively. Furthermore, the film demonstrates excellent biosafety and can be recycled and reused for at least three months. This innovative BNNS/SF film holds great potential for advancing the field of personal thermal management materials.

[Clinical and genetic analysis of ten Chinese pedigrees affected with 7q11.23 duplication syndrome]

OBJECTIVE

To analyze the clinical and genetic characteristics of ten Chinese pedigrees affected with 7q11.23 duplication syndrome.

METHODS

From December 2017 to January 2022, ten pedigrees diagnosed with 7q11.23 duplication syndrome at the First Affiliated Hospital of Zhengzhou University were enrolled as the study subjects. Clinical data of all subjects were collected, and some had subjected to copy number variation sequencing or single nucleotide polymorphism array to analyze the pattern of inheritance.

RESULTS

The probands had included six fetuses and four adolescents. Four of the six prenatal cases showed abnormal ultrasound indicators, including three with soft indicators and one with abnormal fetal structural development. The clinical phenotype of the four adolescent cases had included mental retardation, delayed language development, and attention deficit hyperactivity disorder. The size of the copy number variations had ranged from 1.31 to 1.42 Mb, involving the classic region of 7q11.23 duplication syndrome. Of these, five cases had undergone parental origin testing, three cases were de novo, and two were hereditary.

CONCLUSION

Individuals with 7q11.23 duplication syndrome may show substantial clinical phenotypic heterogeneity, hence the affected families should be provided with pre-pregnancy consultation and reproductive guidance.

[Genetic analysis of a case with Al Kaissi syndrome and a literature review]

OBJECTIVE

To explore the genetic etiology of a child with delayed growth and development and carry out a literature review.

METHODS

A child suspected for Al Kaissi syndrome at the First Affiliated Hospital of Zhengzhou University on March 6, 2021 was selected as the study subject. Following extraction of genomic DNA, the child was subjected to copy number variation sequencing (CNV-seq) and whole exome sequencing (WES), and candidate variants were verified by PCR-agarose gel electrophoresis and quantitative real-time PCR (qPCR). Prenatal diagnosis was conducted on chorionic villi sample upon subsequent pregnancy.

RESULTS

The child, a 6-year-and-4-month-old boy, has dysmorphic features including low-set protruding ears and triangular face, delayed language and intellectual development, and ventricular septal defect. CNV-seq result has found no obvious abnormality, whilst WES revealed homozygous deletion of exons 1 and 2 of the CDK10 gene, which was confirmed by PCR-agarose gel electrophoresis and qPCR. Both of his parents were heterozygous carriers. Prenatal diagnosis using chorionic villi samples suggested that the fetus also carried the heterozygous deletion.

CONCLUSION

The clinical features of Al Kaissi syndrome in this child can probably be attributed to the homozygous deletion of exons 1 and 2 of the CDK10 gene.

Exploring factors impacting haplotype-based noninvasive prenatal diagnosis for single-gene recessive disorders

Haplotype-based noninvasive prenatal diagnosis (NIPD) is applicable for various recessive single-gene disorders in proband families. However, a comprehensive exploration of critical factors influencing the assay performance, such as fetal fraction, informative single nucleotide polymorphism (SNP) count, and recombination events, has yet to be performed. It is critical to identify key factors affecting NIPD performance, including its accuracy and success rate, and their impact on clinical diagnostics to guide clinical practice. We conducted a prospective study, recruiting 219 proband families with singleton pregnancies at risk for eight recessive single-gene disorders (Duchenne muscular dystrophy, spinal muscular atrophy, phenylketonuria, methylmalonic acidemia, hemophilia A, hemophilia B, non-syndromic hearing loss, and congenital adrenal hyperplasia) at 7-14 weeks of gestation. Haplotype-based NIPD was performed by evaluating the relative haplotype dosage (RHDO) in maternal circulation, and the results were validated via invasive prenatal diagnosis or newborn follow-ups. Among the 219 families, the median gestational age at first blood draw was 8+5 weeks. Initial testing succeeded for 190 families and failed for 29 due to low fetal fraction (16), insufficient informative SNPs (9), and homologous recombination near pathogenic variation (4). Among low fetal fraction families, successful testing was achieved for 11 cases after a redraw, while 5 remained inconclusive. Test failures linked to insufficient informative SNPs correlated with linkage disequilibrium near the genes, with F8 and MMUT exhibiting the highest associated failure rates (14.3% and 25%, respectively). Homologous recombination was relatively frequent around the DMD and SMN1 genes (8.8% and 4.8%, respectively) but led to detection failure in only 44.4% (4/9) of such cases. All NIPD results from the 201 successful families were consistent with invasive diagnostic findings or newborn follow-up. Fetal fraction, informative SNPs count, and homologous recombination are pivotal to NIPD performance. Redrawing blood effectively improves the success rate for low fetal fraction samples. However, informative SNPs count and homologous recombination rates vary significantly across genes, necessitating careful consideration in clinical practice. We have designed an in silico method based on linkage disequilibrium data to predict the number of informative SNPs. This can identify genomic regions where there might be an insufficient number of SNPs, thereby guiding panel design. With these factors properly accounted for, NIPD is highly accurate and reliable.

Bionic Design and Optimization on the Flow Channel of a Legged Robot Joint Hydraulic Drive Unit Based on Additive Manufacturing

The joint hydraulic drive unit (HDU) serves as a pivotal element in enabling the high-performance movements of legged robots. Functioning as the conduit linking the oil source and the actuator, the hydraulic flow channel significantly impacts actuator performance. Hence, optimizing the HDU flow channel becomes imperative, enhancing not only HDU efficiency but also the overall system performance. This paper introduces a novel approach by aligning the hydraulic flow channel of the joint HDU with the arteriovenous layout of the cardiac vascular system, departing from the conventional machining flow channel model. Through simulations determining the optimal range of the vascular branch radius and angle, this study guides the design optimization of the joint HDU flow channel. With the primary optimization goal of reducing pressure loss, the study compares simulation outcomes of various flow channel models-linear, variable excessive radius, and the multidimensional Bessel curve-tailored to suit the arrangement specifics of the joint HDU. Further validating these designs, the flow channels are fabricated using additive manufacturing for experimental verification. The integration of simulation analyses and pressure loss testing reveals a remarkable reduction of over 40% in pressure loss for the bionic flow channel compared to the conventional machining form. This empirical evidence strongly substantiates the bionic flow channel's superior efficacy in pressure loss reduction. The findings presented herein offer valuable insights for the development of low-loss flow channels in joint HDUs, thereby presenting a new avenue for designing energy-efficient, high power-to-weight ratio legged robots.

[Analysis of a twin pregnancy with false negative result for 22q11.2 deletion syndrome by expanded non-invasive prenatal testing]

OBJECTIVE

To explore the cause for a twin pregnancy with false negative result for 22q11.2 deletion syndrome by expanded non-invasive prenatal testing (NIPT-plus).

METHODS

A pregnant woman with twin pregnancy through in-vitro fertilization and negative result of NIPT-plus was selected as the study subject. Amniocentesis was conducted after ultrasonic finding of fetal abnormalities. In addition to conventional G-banded karyotyping, copy number variation sequencing (CNV-Seq) was used to detect chromosomal microdeletion and microduplication. Clinical data of the woman were analyzed to explore the reasons underlying the false negative result.

RESULTS

NIPT-plus has yielded a negative result with 11.77 Mb unique reads and 3.05% fetal fraction. Both fetuses had a normal karyotype (46,XY and 46,XX). CNV-seq indicated that one of the fetuses was normal, whilst the other was diagnosed with a 2.58 Mb deletion in the 22q11.2 region.

CONCLUSION

The false negative result may be attributed to the combined influence of low fetal fraction, high BMI, twin pregnancy through IVF and a relatively small deletion fragment. Ultrasonography exam following a low-risk result of NIPT-plus should not be neglected.

Prenatal diagnosis of 1408 foetuses at risk of DMD/BMD by MLPA and Sanger sequencing combined with STR linkage analysis

OBJECTIVE

This study is a retrospective analysis of the prenatal genetic diagnosis results of 1408 foetuses at high risk of DMD/BMD to provide information for clinical genetic counselling.

BACKGROUND

Duchenne muscular dystrophy (DMD) is a severe neuromuscular disorder characterized by skeletal and cardiac muscle weakness. With the deepening of disease research, some treatments have been applied in clinics. Therefore, early and accurate prenatal diagnosis can inform pregnancy choices for high-risk families.

METHODS

A total of 1316 unrelated DMD/BMD families with confirmed genetic diagnoses were recruited from the Genetic and Prenatal Diagnosis Center of the First Affiliated Hospital of Zhengzhou University. Prenatal diagnosis of 1408 high-risk foetuses was performed by MLPA and Sanger sequencing combined with STR linkage analysis for all families.

RESULTS

Among the 1316 families, large deletions, duplications, and small variants of the DMD gene accounted for 70.4% (927/1316), 8.2% (108/1316), and 21.4% (281/1316), respectively. Among 1316 mothers, 863 (65.6%) were carriers, and 453 (34.4%) were not carriers. The rate of de novo variants was 34.4% (453/1316) in our study. In addition, gonadal mosaicism was observed in 11 pregnant females. Prenatal diagnosis was provided for 1408 high-risk foetuses; 282 foetuses were identified as male patients, 219 foetuses were female carriers, and the remainder had normal genetics. The results of prenatal diagnosis were consistent with the results of follow-up.

CONCLUSIONS

Accurate and rapid prenatal diagnosis can be achieved using MLPA, Sanger sequencing, and STR linkage analysis. Furthermore, germline mosaicism in DMD should not be ignored; considering this, a prenatal diagnosis for all pregnant women with a family history of DMD/BMD regardless of whether they carried disease-causing variants is proposed. Genetic counselling and targeted prenatal diagnosis will continue to be a cornerstone of DMD/BMD family management in the future.

Anisotropic Black Phosphorene Structural Modulation for Thermal Storage and Solar-Thermal Conversion

Exploiting novel strategies for simultaneously harvesting ubiquitous, renewable, and easily accessible solar energy based on the photothermal effect, and efficiently storing the acquired thermal energy plays a vital role in revolutionizing the current fossil fuel-dominating energy structure. Developing black phosphorene-based phase-change composites with optimized photothermal conversion efficiencyand high latent heat is the most promising way to achieve efficient solar energy harvesting and rapid thermal energy storage. However, exfoliating high-quality black phosphorene nanosheets  remains challenging, Furthermore, an efficient strategy that can construct the aligned black phosphorene frameworks to maximize thermal conductivity enhancement is still lacking. Herein, high-quality black phosphorene nanosheets are prepared by an optimized exfoliating strategy. Meanwhile, by regulating the temperature gradient during freeze-casting, the framework consisting of shipshape aligned black phosphorene at long-range is successfully fabricated, improving the thermal conductivity of the poly(ethylene glycol) matrix up to 1.81 W m-1  K-1 at 20 vol% black phosphorene loading. The framework also endows the composite with excellent phase-change material encapsulation capacity and  high latent heat of 103.91 J g-1 . It is envisioned that the work advances the paradigm of contrasting frameworks with nanosheets toward controllable structure thermal enhancement of the composites.

Insights into genetic diversity and phenotypic variations in domestic geese through comprehensive population and pan-genome analysis

BACKGROUND

Domestic goose breeds are descended from either the Swan goose (Anser cygnoides) or the Greylag goose (Anser anser), exhibiting variations in body size, reproductive performance, egg production, feather color, and other phenotypic traits. Constructing a pan-genome facilitates a thorough identification of genetic variations, thereby deepening our comprehension of the molecular mechanisms underlying genetic diversity and phenotypic variability.

RESULTS

To comprehensively facilitate population genomic and pan-genomic analyses in geese, we embarked on the task of 659 geese whole genome resequencing data and compiling a database of 155 RNA-seq samples. By constructing the pan-genome for geese, we generated non-reference contigs totaling 612 Mb, unveiling a collection of 2,813 novel genes and pinpointing 15,567 core genes, 1,324 softcore genes, 2,734 shell genes, and 878 cloud genes in goose genomes. Furthermore, we detected an 81.97 Mb genomic region showing signs of genome selection, encompassing the TGFBR2 gene correlated with variations in body weight among geese. Genome-wide association studies utilizing single nucleotide polymorphisms (SNPs) and presence-absence variation revealed significant genomic associations with various goose meat quality, reproductive, and body composition traits. For instance, a gene encoding the SVEP1 protein was linked to carcass oblique length, and a distinct gene-CDS haplotype of the SVEP1 gene exhibited an association with carcass oblique length. Notably, the pan-genome analysis revealed enrichment of variable genes in the "hair follicle maturation" Gene Ontology term, potentially linked to the selection of feather-related traits in geese. A gene presence-absence variation analysis suggested a reduced frequency of genes associated with "regulation of heart contraction" in domesticated geese compared to their wild counterparts. Our study provided novel insights into gene expression features and functions by integrating gene expression patterns across multiple organs and tissues in geese and analyzing population variation.

CONCLUSION

This accomplishment originates from the discernment of a multitude of selection signals and candidate genes associated with a wide array of traits, thereby markedly enhancing our understanding of the processes underlying domestication and breeding in geese. Moreover, assembling the pan-genome for geese has yielded a comprehensive apprehension of the goose genome, establishing it as an indispensable asset poised to offer innovative viewpoints and make substantial contributions to future geese breeding initiatives.

[Prenatal diagnosis of a case with Schuurs-Hoeijmakers syndrome]

OBJECTIVE

To explore the genetic basis for a fetus with multiple malformations.

METHODS

Clinical data of the fetus was collected, Amniotic fluid sample of the fetus was subjected to conventional G-banded karyotyping, low-depth whole genome copy number variants detection and whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing of the fetus and its parents.

RESULTS

Prenatal ultrasound scan at 21+5 gestational weeks had revealed increased nuchal thickness (9.0 mm), enhanced echos of bilateral renal parenchyma, seroperitoneum, left pleural effusion and right displacement of the heart. The mother had a previous history of terminated pregnancy for multiple fetal anomalies. No abnormality was found by conventional karyotyping and CNV analysis, though WES revealed that the fetus has harbored a de novo heterozygous c.607C>T (p.Arg203Trp) variant of the ACS1 gene (NM_018026.3), and the result was validated by Sanger sequencing.

CONCLUSION

Through WES and prenatal ultrasonography, the fetus was diagnosed with Schuurs-Hoeijmakers syndrome due to the heterozygous c.607C>T (p.Arg203Trp) variant of the PACS1 gene (NM_018026.3). For fetuses with multiple malformations, WES can help to reveal the genetic etiology when CNV result is negative.

[Genetic testing and prenatal diagnosis for two Chinese pedigrees affected with Alport syndrome due to variants of COL4A5 gene]

OBJECTIVE

To analysis variants of COL4A5 gene in two Chinese pedigrees affected with Alport syndrome (AS) and provide prenatal diagnosis for them.

METHODS

Two unrelated ethnic Han Chinese pedigrees who had visited the First Affiliated Hospital of Zhengzhou University respectively in September 2018 and January 2020 were selected as the study subjects. Clinical data were collected, and genomic DNA was extracted from peripheral venous blood and amniotic fluid samples for genetic testing. Following next generation sequencing, candidate variants of the COL4A5 gene were verified by Sanger sequencing and bioinformatic analysis. The gender of the fetuses was determined by the presence of sex-determining region on Y (SRY).

RESULTS

Genetic testing revealed that the proband and a fetus from pedigree 1 had both harbored a c.2723G>A (p.Gly908Glu) variant in exon 32 of the COL4A5 gene, whilst the proband and a fetus from pedigree 2 had both harbored a c.3817G>A (p.Gly1273Asp) variant in exon 44 of the COL4A5 gene. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), both variants were classified as likely pathogenic (PP2+PM2_Supporting). Following exclusion of maternal contamination, PCR amplification of the SRY region indicated that both fetuses were males.

CONCLUSION

The c.2723G>A (p.Gly908Glu) and c.3817G>A (p.Gly1273Asp) variants of the COL4A5 gene probably underlay the AS in the two pedigrees. Detection of the SRY region can reliably identify the fetal sex, which is conducive to the prenatal diagnosis. Above results have also enriched the mutational spectrum of the COL4A5 gene and provided a reference for correlating the genotype and phenotype of the AS.

[Genetic testing and prenatal diagnosis for a Chinese pedigree affected with Waardenburg syndrome type 4C due to heterozygous deletion of SOX10 gene]

OBJECTIVE

To explore the genetic basis for a Chinese pedigree featuring congenital profound syndromic deafness and chronic constipation, and provide prenatal diagnosis for a high-risk fetus.

METHODS

Whole-exome sequencing was carried out to analyze the sequences of genes associated with hereditary deafness, and multiplex ligation-dependent probe amplification (MLPA) was used to verify the candidate variant in the proband's parents and the fetus.

RESULTS

The proband was found to have harbored a heterozygous deletion of SOX10, a pathogenic gene associated with Waardenburg syndrome type 4C (WS4C). The same deletion was found in her mother (with profound syndromic deafness and chronic constipation) and the fetus, but not in her father with normal hearing. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG) and Association for Molecular Pathology (AMP), the SOX10 gene deletion was predicted to be a pathogenic variant (PVS1+PM2_Supporting+PP1+PP4).

CONCLUSION

The pedigree was diagnosed with WS4C, which has conformed to an autosomal dominant inheritance. Deletion of the entire SOX10 gene, as a loss-of-function variant, probably underlay its pathogenesis. Above finding has facilitated genetic counseling and prenatal diagnosis for this family.

[Genetic analysis of a rare case with Disorder of sex development due to structural rearrangement of Y chromosome]

OBJECTIVE

To explore the genetic basis for a rare case with Disorder of sex development.

METHODS

Clinical data of the patient was collected. Chromosomal karyotyping, SRY gene testing, whole exome sequencing (WES), low-coverage massively parallel copy number variation sequencing (CNV-seq), fluorescence in situ hybridization (FISH), and whole genome sequencing (WGS) were carried out.

RESULTS

The patient, a 14-year-old female, had manifested short stature and dysplasia of second sex characteristics. She was found to have a 46,XY karyotype and positive for the SRY gene. No pathogenic variant was found by WES, except a duplication at Yp11.32q12. The result of CNV-seq was 47,XYY. FISH has confirmed mosaicism for a dicentric Y chromosome. A 23.66 Mb duplication on Yp11.32q11.223 and a 5.16 Mb deletion on Yq11.223q11.23 were found by WGS. The breakpoint was mapped at chrY: 23656267. The patient's karyotype was ultimately determined as 46,X,psu idic(Y)(q11.223)/46,X,del(Y)(q11.223).

CONCLUSION

The combination of multiple methods has facilitated clarification of the genetic etiology in this patient, which has provided a reference for the clinical diagnosis and treatment.

Synthesis of Multifunctional Mn3O4-Ag2S Janus Nanoparticles for Enhanced T1-Magnetic Resonance Imaging and Photo-Induced Tumor Therapy

The global burden of cancer is increasing rapidly, and nanomedicine offers promising prospects for enhancing the life expectancy of cancer patients. Janus nanoparticles (JNPs) have garnered considerable attention due to their asymmetric geometry, enabling multifunctionality in drug delivery and theranostics. However, achieving precise control over the self-assembly of JNPs in solution at the nanoscale level poses significant challenges. Herein, a low-temperature reversed-phase microemulsion system was used to obtain homogenous Mn3O4-Ag2S JNPs, which showed significant potential in cancer theranostics. Structural characterization revealed that the Ag2S (5-10 nm) part was uniformly deposited on a specific surface of Mn3O4 to form a Mn3O4-Ag2S Janus morphology. Compared to the single-component Mn3O4 and Ag2S particles, the fabricated Mn3O4-Ag2S JNPs exhibited satisfactory biocompatibility and therapeutic performance. Novel diagnostic and therapeutic nanoplatforms can be guided using the magnetic component in JNPs, which is revealed as an excellent T1 contrast enhancement agent in magnetic resonance imaging (MRI) with multiple functions, such as photo-induced regulation of the tumor microenvironment via producing reactive oxygen species and second near-infrared region (NIR-II) photothermal excitation for in vitro tumor-killing effects. The prime antibacterial and promising theranostics results demonstrate the extensive potential of the designed photo-responsive Mn3O4-Ag2S JNPs for biomedical applications.

Structural variations in crocodile lizard populations provide novel insights into genomic variations in endangered animals

Population-scale genome resequencing of endangered animals may contribute to gaining an understanding of how genomes vary as population sizes become smaller, as well as the functional implications of such variation. In this study, we analysed structural variations and gene presence and absence variations in the genomes of population of the endangered crocodile lizards. We found that the frequencies of some genes showed significant differences between crocodile lizards in different regions, indicating the influence of environmental selection, as well as potential contributions from demography and isolation, in shaping gene presence and absence variations. The haplotype diversity of major histocompatibility complex (MHC) genes was also found to differ among crocodile lizards inhabiting different regions. These findings indicate that well-designed interbreeding of crocodile lizards from different regions may facilitate the exchange of genes between different lizard populations and increase the haplotype diversity of MHC genes, which may be beneficial for the survival of these lizards. Our findings in this study, based on differences in gene structural variation, provide new insights into genomic variation and may contribute to the conservation of endangered animals.

Haplotype-based noninvasive prenatal diagnosis of methylmalonic acidemia and the discovery of a recurrent pathogenic haplotype associated with c.609G>A

BACKGROUND

Early diagnosis and intervention are crucial for the prognosis of methylmalonic acidemia (MMA). However, research focused on early prenatal diagnosis of MMA is limited.

METHODS

A 161.89kb capture panel was designed for selectively enriching highly heterozygous SNPs. Fetal genotypes were inferred using relative haplotype dosage (RHDO) and Bayes factor, followed by invasive prenatal diagnosis (IPD) for validation. A core pathogenic haplotype associated with c.609G>A was identified based on the frequency differences between pathogenic and normal haplotypes.

RESULTS

We recruited 41 pregnancies at risk of MMA with a median gestational age of 8+2  weeks. The assay success rate of NIPD-MMA for maternal variants was 92.7% (38/41), and after incorporating the paternal result, the overall assay success rate reached 100% (41/41). All NIPD results were concordant with IPD. Notably, a core haplotype (hap_2), comprising 28 SNPs, demonstrates significant enrichment within pathogenic haplotypes bearing the c.609G>A variation. On average, c.609G>A carriers had 22.38 heterozygous loci within these 28 SNPs.

CONCLUSION

NIPD-MMA presents a viable choice for early, accurate, and safe prenatal diagnosis. Furthermore, the discovery of the recurrent core pathogenic haplotype provides a novel approach for haplotype phasing and has the potential for realizing proband-independent NIPD in the future.

Hydrothermal Extraction and Characterization of Natural Hydroxyapatite from Waste Bovine Femur Bone

The management of large amounts of bio-wastes, such as bovine femurs from kitchens and slaughterhouses, has long been a challenging issue. However, through the utilization of a hydrothermal process, it is possible to transform these bio-wastes into valuable products. In this study, we focused on extracting hydroxyapatite (HAp), the primary inorganic component of bovine femurs, for potential use in bone tissue engineering scaffolds. By subjecting the femurs to hydrothermal treatment at varying times and solvents, we successfully decomposed and removed the organic matter present, resulting in the extraction of HAp. To comprehensively evaluate the properties of the extracted HAp, we employed several characterization techniques that provided valuable insights into the structure, morphology, and elemental composition of the extracted HAp. Furthermore, we conducted a Cell Counting Kit-8 assay, which confirmed the favorable biocompatibility of the extracted HAp. Overall, this study highlights the potential of hydrothermal treatment as an environmentally friendly and cost-effective method for handling bio-waste, specifically bovine femurs. The extracted HAp exhibits promising characteristics, making it suitable for a wide range of biomedical applications. This research contributes to the sustainable utilization of bio-waste and underscores the importance of resourceful exploitation for environmental protection.

[Analysis of a Chinese pedigree affected with Meckel syndrome due to variants of TMEM67 gene]

OBJECTIVE

To explore the genetic etiology for a Chinese pedigree affected with Meckel syndrome.

METHODS

A pedigree with a history of three consecutive adverse pregnancies which presented at the First Affiliated Hospital of Zhengzhou University on August 31, 2017 was selected as the study subject. Clinical data of the pedigree were collected. High-throughput sequencing was carried out to screen for variants of ciliopathy-related genes in the third fetus following induced abortion, and candidate variant was verified by Sanger sequencing.

RESULTS

The first pregnancy of the couple had ended as spontaneous abortion, whilst the fetus of the second pregnancy was suspected for having ciliopathy, though no genetic testing was carried out following elected abortion. The fetus of the third pregnancy was suspected for having ciliopathy, and high-throughput sequencing and Sanger sequencing had shown that the fetus had harbored compound heterozygous variants of the TMEM67 gene, including c.978+1G>A from the father and c.1288G>C (p.D430H) from the mother. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the c.978+1G>A was classified as a pathogenic variant (PVS1+PM2_Supporting+PP5), whilst the newly discovered c.1288G>C (p.D430H) was classified as a likely pathogenic variant (PM2_Supporting+PM3+PM5+PP3).

CONCLUSION

The c.978+1G>A and c.1288G>C (p.D430H) compound heterozygous variants of the TMEM67 gene probably underlay the three consecutive adverse pregnancies suspected for ciliopathy in this pedigree. The discovery of c.1288G>C (p.D430H) has also expanded the mutational spectrum of the TMEM67 gene.

Metformin Hydrochloride Significantly Inhibits Rotavirus Infection in Caco2 Cell Line, Intestinal Organoids, and Mice

Rotavirus is one of the main pathogens that causes severe diarrhea in children under the age of 5, primarily infecting the enterocytes of the small intestine. Currently, there are no specific drugs available for oral rehydration and antiviral therapy targeting rotavirus. However, metformin hydrochloride, a drug known for its antiviral properties, shows promise as it accumulates in the small intestine and modulates the intestinal microbiota. Therefore, we formulated a hypothesis that metformin hydrochloride could inhibit rotavirus replication in the intestine. To validate the anti-rotavirus effect of metformin hydrochloride, we conducted infection experiments using different models, ranging from in vitro cells and organoids to small intestines in vivo. The findings indicate that a concentration of 0.5 mM metformin hydrochloride significantly inhibits the expression of rotavirus mRNA and protein in Caco-2 cells, small intestinal organoids, and suckling mice models. Rotavirus infections lead to noticeable pathological changes, but treatment with metformin has been observed to mitigate the lesions caused by rotavirus infection in the treated group. Our study establishes that metformin hydrochloride can inhibit rotavirus replication, while also affirming the reliability of organoids as a virus model for in vitro research.

[Genetic diagnosis of Branchio-Oto syndrome pedigree due to a de novo heterozygous deletion of EYA1 gene]

OBJECTIVE

To explore the genetic basis for a Chinese pedigree affected with Branchio-Oto syndrome (BOS).

METHODS

A pedigree with BOS which had presented at the Genetics and Prenatal Diagnosis Center of the First Affiliated Hospital of Zhengzhou University in May 2021 was selected as the study subject. Clinical data of the pedigree was collected. Peripheral blood samples of the proband and her parents were collected. Whole exome sequencing (WES) was carried out for the proband. Multiplex ligation-dependent probe amplification (MLPA) was used to verify the result of WES, short tandem repeat (STR) analysis was used to verify the relationship between the proband and her parents, and the pathogenicity of the candidate variant was analyzed.

RESULTS

The proband, a 6-year-old girl, had manifested severe congenital deafness, along with inner ear malformation and bilateral branchial fistulae. WES revealed that she has harbored a heterozygous deletion of 2 466 kb at chromosome 8q13.3, which encompassed the EYA1 gene. MLPA confirmed that all of the 18 exons of the EYA1 gene were lost, and neither of her parents has carried the same deletion variant. STR analysis supported that both of her parents are biological parents. Based on the guidelines from the American College of Medical Genetics and Genomics, the deletion was classified as pathogenic (PVS1+PS2+PM2_Supporting+PP4).

CONCLUSION

The heterozygous deletion of EYA1 gene probably underlay the pathogenicity of BOS in the proband, which has provided a basis for the clinical diagnosis.

[Clinical characteristics and genetic analysis of a Chinese pedigree affected with Alström syndrome]

OBJECTIVE

To explore the clinical characteristics and genetic etiology of a Chinese pedigree affected with Alström syndrome.

METHODS

A pedigree with 5 members affected with Alström syndrome who had visited the First Affiliated Hospital of Zhengzhou University in February 2021 was selected as the study subject. Clinical data of the pedigree were collected, and peripheral venous blood samples were collected for the extraction of genomic DNA. Genetic testing was carried out for the eldest daughter and third son through whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing and bioinformatic analysis.

RESULTS

The eldest daughter (14 years old) and the third son (11 years old) both had congenital nystagmus, amblyopia, growth retardation and type 2 diabetes. WES revealed that both had harbored homozygous c.3538A>T (p.Lys1180*) variant of the ALMS1 gene. Sanger sequencing confirmed that the father, mother, and second daughter were all heterozygous carriers. Based on the Guidelines for Genetic Variation and the Technical Standards for Interpretation and Reporting of Primary Copy Number Variations, the variant was predicted as pathogenic (PVS1+PM2_Supporting+PP4).

CONCLUSION

The homozygous c.3538A>T (p.Lys1180*) variant of the ALSM1 gene probably underlay the Alström syndrome in this pedigree, which has provided a reference for the clinical treatment.

Recent Advances in Sources of Bio-Inspiration and Materials for Robotics and Actuators

Bionic robotics and actuators have made dramatic advancements in structural design, material preparation, and application owing to the richness of nature and innovative material design. Appropriate and ingenious sources of bio-inspiration can stimulate a large number of different bionic systems. After millennia of survival and evolutionary exploration, the mere existence of life confirms that nature is constantly moving in an evolutionary direction of optimization and improvement. To this end, bio-inspired robots and actuators can be constructed for the completion of a variety of artificial design instructions and requirements. In this article, the advances in bio-inspired materials for robotics and actuators with the sources of bio-inspiration are reviewed. The specific sources of inspiration in bionic systems and corresponding bio-inspired applications are summarized first. Then the basic functions of materials in bio-inspired robots and actuators is discussed. Moreover, a principle of matching biomaterials is creatively suggested. Furthermore, the implementation of biological information extraction is discussed, and the preparation methods of bionic materials are reclassified. Finally, the challenges and potential opportunities involved in finding sources of bio-inspiration and materials for robotics and actuators in the future is discussed.

[Clinical efficacy and safety of venetoclax combined with multidrug chemotherapy in the treatment of 15 patients with relapsed or refractory early T-cell precursor acute lymphoblastic leukemia]

Objective: To explore the efficacy and safety of Venetoclax combined with multidrug chemotherapy in patients with relapsed or refractory early T-cell precursor acute lymphoblastic leukemia (R/R ETP-ALL) . Methods: This study retrospectively analyzed 15 patients with R/R ETP-ALL who received Venetoclax combined with multidrug chemotherapy from December 2018 to February 2022. Among them, eight cases were combined with demethylated drugs, four cases were combined with demethylated drugs and HAAG chemotherapy regimen, two cases were combined with demethylated drugs and CAG regimen, and one case was combined with Cladribine. Specific usage and dosage of Venetoclax: 100 mg on day 1, 200 mg on day 2, 400 mg on day 3-28, orally; when combined with azole antifungal drugs, dosage was reduced to 100 mg/d. Results: Fifteen patients (10 males and 5 females) with R/R ETP-ALL were treated with Venetoclax and multidrug chemotherapy with a median age of 35 (12-42) years old. Of 4 refractory and 11 relapsed patients, the efficacy was evaluated on the 21th day following combined chemotherapy: the overall response rate, the complete response (CR) rate, and the CR with incomplete hematological recovery (CRi) rate were 67.7% (10/15), 60.0% (9/15), and 6.7% (1/15), respectively. For the overall study population, the 12-month overall survival (OS) rate was 60.0%, and the median OS was 17.7 months. The disease-free survival (DFS) rate of all CR patients at 12 months was 60.0%, and the median DFS did not reach. About 14 patients had Ⅲ-Ⅳ hematological toxicity, but these adverse reactions were all controllable. No adverse reaction in the nervous system and tumor lysis syndrome occurred in this study, and no adverse reaction of organs above grade Ⅲ occurred. Conclusion: Venetoclax combined with multidrug chemotherapy may be a safe and promising treatment option for patients with R/R ETP-ALL.

[Clinical phenotype and genetic analysis of a patient with a heterozygous 6p25.3 deletion and partial trisomy 15q]

OBJECTIVE

To investigate the clinical phenotype and genetic characteristics of a patient with a heterozygous 6p25.3 deletion and partial trisomy 15q.

METHODS

A patient who had presented at the Genetics and Prenatal Diagnosis Center of the First Affiliated Hospital of Zhengzhou University on May 14, 2021 was selected as the study subject. Clinical data of the patient was collected, and G-banded chromosomal karyotyping and copy number variation sequencing (CNV-seq) were carried out.

RESULTS

The patient's main clinical features have included complete uterine septum, vaginal septum, atrophy of left eyeball, abnormal fingers and toes, and mental retardation. The karyotype of the patient was 46,XX,der(6)t(6;15)(p25.3;q26.1). CNV-seq result has indicated a 1.20 Mb heterozygous deletion in the 6p25.3 region and a 10.20 Mb duplication in the 15q26.1q26.3 region. The deletion segment has included the FOXQ1 gene, which may be related with the abnormal development of the left eye. The duplication segment has a 96.16% overlap with the region associated with 15q26 overgrowth syndrome (including the IGF1R gene), which may be related to the patient' s abnormal development of the Müllerian duct, abnormal fingers and toes, and mental developmental delay.

CONCLUSION

The heterozygous deletion of the 6p25.3 region and duplication of the 15q26.1q26.3 region probably underlay the abnormal clinical phenotype in this patient.

[The value of combined CNV-Seq and chromosomal karyotyping for the detection of amniocytic mosaicisms and a literature review]

OBJECTIVE

To assess the value of combined copy number variation sequencing (CNV-seq) and chromosomal karyotyping for the diagnosis of amniocytic mosaicisms, in addition with a literature review.

METHODS

Forty cases of amniocytic mosaicisms detected at the Genetic and Prenatal Diagnosis Center of the First Affiliated Hospital of Zhengzhou University from January 2018 to December 2021, in addition with 245 mosaicisms retrieved from 11 recent literature were evaluated in terms of detection rate, consistency rate, and pregnancy outcomes.

RESULTS

The detection rate of amniocytic mosaicisms was 0.46% (40/8 621) in our center. And its consistency rate with chromosomal karyotyping was 75.0% (30/40). After genetic counseling, 30 (75.0%) couples had opted to terminate the pregnancy, 5 (12.5%) had decided to continue with the pregnancy, 3 (7.5%) fetuses were born alive, and 2 cases (5.0%) were lost in touch. By contrast, 245 cases (0.39%) of mosaicisms were identified among 63 577 amniotic samples, with a consistency rate of 62.8% (103/164) with other techniques. Among these, 114 cases (55.1%) were terminated, 75 (36.2%) were born alive, and 18 (8.7%) were lost during the follow up.

CONCLUSION

Combined CNV-seq and chromosomal karyotyping has a high value for the detection of amniotic mosaicisms.

The uncertainty of copy number variants: pregnancy decisions and clinical follow-up

BACKGROUND

Next-generation sequencing for copy number variants is often used as a follow-up investigation of unusual fetal ultrasound results and is capable of detecting copy number variations with a resolution of ∼0.1 Mb. In a prenatal setting, observation and subsequent management of pregnancies with a fetal variant of uncertain significance remains problematic for counseling.

OBJECTIVE

This study aimed to follow the decision-making processes in pregnancies with a fetal variant of uncertain significance and prospectively assess copy number variation interpretations and implications under the newer 2020 American College of Medical Genetics and Genomics guidelines.

STUDY DESIGN

In a single prenatal unit, prospective chromosome testing using copy number variation sequencing for 8030 fetuses with unexpected noninvasive findings identified 139 pregnancies with a copy number variation classified as a variant of uncertain significance according to the 2015 American College of Medical Genetics and Genomics guidelines current at the time. Parent-of-origin testing was subsequently performed to determine if the copy number variation was inherited or de novo. All couples were offered specialized genetic counseling to assist in pregnancy management decisions. For the continued pregnancies that reached term, newborns were clinically assessed for evidence of any disease at 0 to 10 months and/or at 2 to 4 years of age.

RESULTS

Of the 139 variants of uncertain significance found, most (78%) were inherited with no evidence of disease in the carrier parent. On the basis of primary ultrasound findings combined with results from noninvasive prenatal screening tests, most inherited variant of uncertain significance pregnancies were continued, whereas most pregnancies involving de novo variants of uncertain significance were terminated. From clinical follow-up of the 113 live births, only 5 showed any evidence of a phenotype that was not apparently related to the original variant of uncertain significance. Prospective reanalysis of the 139 variants of uncertain significance using recent 2020 American College of Medical Genetics and Genomics guidelines changed the status of 24 variants of uncertain significance, with 15 reclassified as benign and 9 as pathogenic. However, the 5 children born with an inherited variant of uncertain significance reclassified as pathogenic showed no evidence of a disease phenotype on clinical follow-up.

CONCLUSION

The severity of fetal ultrasound findings combined with results from parent-of-origin testing were the key drivers in pregnancy management decisions for patients. According to birth outcomes from continued pregnancies, most variants of uncertain significance proved to be apparently benign in nature and potentially of low risk of adverse disease outcome. There was a discordance rate of 17% for variant of uncertain significance scoring between the 2015 and 2020 American College of Medical Genetics and Genomics guidelines for defining a variant of uncertain significance, suggesting that difficulties remain for predicting true pathogenicity. Nonetheless, with increasing knowledge of population copy number variation polymorphisms, and a more complete assessment for alternative genetic causes, patients having prenatal assessments should feel less anxious when a fetal variant of uncertain significance is identified.

Microfluidic fabrication of X-ray-visible sodium hyaluronate microspheres for embolization

Catheter embolization is a minimally invasive technique that relies on embolic agents and is now widely used to treat various high-prevalence medical diseases. Embolic agents usually need to be combined with exogenous contrasts to visualize the embolotherapy process. However, the exogenous contrasts are quite simply washed away by blood flow, making it impossible to monitor the embolized location. To solve this problem, a series of sodium hyaluronate (SH) loaded with bismuth sulfide (Bi₂S₃) nanorods (NRs) microspheres (Bi₂S₃@SH) were prepared in this study by using 1,4-butaneglycol diglycidyl ether (BDDE) as a crosslinker through single-step microfluidics. Bi₂S₃@SH-1 microspheres showed the best performance among other prepared microspheres. The fabricated microspheres had uniform size and good dispersibility. Furthermore, the introduction of Bi₂S₃ NRs synthesized by a hydrothermal method as Computed Tomography (CT) contrast agents improved the mechanical properties of Bi₂S₃@SH-1 microspheres and endowed the microspheres with excellent X-ray impermeability. The blood compatibility and cytotoxicity test showed that the Bi₂S₃@SH-1 microspheres had good biocompatibility. In particular, the in vitro simulated embolization experiment results indicate that the Bi₂S₃@SH-1 microspheres had excellent embolization effect, especially for the small-sized blood vessels of 500-300 and 300 μm. The results showed the prepared Bi₂S₃@SH-1 microspheres have good biocompatibility and mechanical properties, as well as certain X-ray visibility and excellent embolization effects. We believe that the design and combination of this material has good guiding significance in the field of embolotherapy.

Dynamic Metal-Ligand Coordination Boosts CO2 Electroreduction

The interfacial structure of heterogeneous catalysts determines the reaction rate by adjusting the adsorption behavior of reaction intermediates. Unfortunately, the catalytic performance of conventionally static active sites has always been limited by the adsorbate linear scaling relationship. Herein, we develop a triazole-modified Ag crystal (Ag crystal-triazole) with dynamic and reversible interfacial structures to break such a relationship for boosting the catalytic activity of CO₂ electroreduction into CO. On the basis of surface science measurements and theoretical calculations, we demonstrated the dynamic transformation between adsorbed triazole and adsorbed triazolyl on the Ag(111) facet induced by metal-ligand conjugation. During CO₂ electroreduction, Ag crystal-triazole with the dynamically reversible transformation of ligands exhibited a faradic efficiency for CO of 98% with a partial current density for CO as high as -802.5 mA cm^-2. The dynamic metal-ligand coordination not only reduced the activation barriers of CO₂ protonation but also switched the rate-determining step from CO₂ protonation to the breakage of C-OH in the adsorbed COOH intermediate. This work provided an atomic-level insight into the interfacial engineering of the heterogeneous catalysts toward highly efficient CO₂ electroreduction.

[Prenatal diagnosis and pregnancy outcome of fetuses with rare autosomal trisomies indicated by non-invasive prenatal testing]

OBJECTIVE

To analyze the result of prenatal diagnosis and outcome of pregnancy for fetuses with rare autosomal trisomies (RATs) suggested by non-invasive prenatal testing (NIPT).

METHODS

A total of 69 608 pregnant women who underwent NIPT at Genetics and Prenatal Diagnosis Center of the First Affiliated Hospital of Zhengzhou University from January 2016 to December 2020 were selected as study subjects. The result of prenatal diagnosis and outcome of pregnancy for those with a high risk for RATs were retrospectively analyzed.

RESULTS

Among the 69 608 pregnant women, the positive rate of NIPT for high-risk RATs was 0.23% (161/69 608), with trisomy 7 (17.4%, 28/161) and trisomy 8 (12.4%, 20/161) being the most common, and trisomy 17 (0.6%, 1/161) being the rarest. For 98 women who had accepted invasive prenatal diagnosis, 12 fetal chromosomal abnormalities were confirmed, and in 5 cases the results were consistent with those of NIPT, which yielded a positive predictive value of 5.26%. Among the 161 women with a high risk for RATs, 153 (95%) were successfully followed up. 139 fetuses were ultimately born, with only one being clinically abnormal.

CONCLUSION

Most women with a high risk for RATs by NIPT have good pregnancy outcomes. Invasive prenatal diagnosis or serial ultrasonography to monitor fetal growth, instead of direct termination of pregnancy, is recommended.

Advanced biomaterials for human glioblastoma multiforme (GBM) drug delivery

Glioblastoma multiforme (GBM) has several distinctive characteristics linked to a poor early-stage prognosis. The crucial obstacle in the treatment of GBM is the inability of chemo drugs or other anticancer medicines to reach brain tumors due to the blood-brain tumor barrier (BBTB), leading to weak cytotoxic activity and drug resistance. Additionally, there is a limited number of clinically approved anticancer medicines for GBM because of the heterogeneity of this type of tumor. Presently, four FDA-approved drugs are available for the treatment of GBM, i.e., temozolomide, lomustine, carmustine, and bevacizumab. These drugs are primarily used to treat recurrent high-grade gliomas and their symptoms. Unfortunately, despite efforts to treat GBM over the last 60 years, no significant progress has been made in extending the overall survival (OS) of patients with this disease. Therefore, possible treatments and accessible drugs must be modified or advanced medicines developed to treat GBM. Several innovative strategies have been used to overcome these challenges, such as combining traditional therapies with emerging nanoscale-based biomaterials for multifunctional characteristics. These modified nanoscale biomaterials can cross the blood-brain barrier (BBB) and increase chemo-drug sensitivity through improved accumulation and efficiency. Herein, we review the recent developments in organic and inorganic biomaterial-based nanoparticles for GBM drug delivery. Firstly, we present a brief overview of the FDA-approved drugs and some additional chemo drugs for treating GBM, followed by a discussion on the drawbacks of the delivery of these drugs in GBM. Further, the current challenges in the field of GBM drug delivery, significant advancements in biomaterials research to overcome these obstacles, and subsequent considerations and opportunities for the application of biomaterials in the clinical treatment of GBM are highlighted.

Detection of male 2+0 and 1+0 carriers for spinal muscular atrophy by digital PCR

Spinal muscular atrophy (SMA) is an autosomal recessive disease with a high carrier frequency. While current screening methods can identify 1+0 carriers, detecting 2+0 genotypes remains challenging, highlighting the need for additional research. Herein, we applied Digital Polymerase Chain Reaction (dPCR) to develop a novel approach for the detection of male carriers (DMC), especially for those with a 2+0 genotype. The clinical utility of DMC was evaluated in 39 semen samples. Multiple ligation-dependent probe amplification (MLPA) and pedigree analysis were performed on genomic DNA from 111 males and their family members. DMC identified 1+1, 2+1, and 1+0 genotypes in 21, 1, and 8 subjects. Importantly, seven men were identified as 2+0 carriers, while two men were excluded from the 2+0 carrier status. The results of DMC were consistent with those of MLPA and pedigree analysis. DMC provides an inexpensive and accurate method for determining the 2+0 and 1+0 genotypes.

Dynamically Reversible Interconversion of Molecular Catalysts for Efficient Electrooxidation of Propylene into Propylene Glycol

For the electrooxidation of propylene into 1,2-propylene glycol (PG), the process involves two key steps of the generation of *OH and the transfer of *OH to the C═C bond in propylene. The strong *OH binding energy (E_B(*OH)) favors the dissociation of H₂O into *OH, whereas the transfer of *OH to propylene will be impeded. The scaling relationship of the E_B(*OH) plays a key role in affecting the catalytic performance toward propylene electrooxidation. Herein, we adopt an immobilized Ag pyrazole molecular catalyst (denoted as AgPz) as the electrocatalyst. The pyrrolic N-H in AgPz could undergo deprotonation to form pyrrolic N (denoted as AgPz-H_vac), which can be protonated reversibly. During propylene electrooxidation, the strong E_B(*OH) on AgPz favors the dissociation of H₂O into *OH. Subsequently, the AgPz transforms into AgPz-H_vac that possesses weak E_B(*OH), benefiting to the further combination of *OH and propylene. The dynamically reversible interconversion between AgPz and AgPz-H_vac accompanied by changeable E_B(*OH) breaks the scaling relationship, thus greatly lowering the reaction barrier. At 2.0 V versus Ag/AgCl electrode, AgPz achieves a remarkable yield rate of 288.9 mmol_PG g_cat^-1 h^-1, which is more than one order of magnitude higher than the highest value ever reported.

[Hepatitis B virus down-regulates the expression of inhibin and promotes the proliferation and survival of hepatocellular carcinoma cells]

Objective: To investigate the effect and role of the hepatitis B virus (HBV) on the expression of inhibin (PHB) in the proliferation and survival of hepatocellular carcinoma (HCC) cells. Methods: The expression of PHB in 13 pairs of HBV-infected livers, normal livers and HepG2.2.15 and HepG2 cells was detected by real-time fluorescent quantitative PCR and Western blot. Liver tissues were collected from seven patients with chronic hepatitis B before and after antiviral (tenofovir) treatment, and the expression of PHB was detected by RT-PCR and Western blot. HepG2.2.15 cells were transfected with Pcmv6-AC-GFP-PHB, and control vectors were collected. DNA content was analyzed by flow cytometry. The proliferation level of each cell group was detected using the EdU cell proliferation assay. HepG2.2.15 cells transfected with Pcmv6-AC-GFP-PHB and the control vector were cultured in serum-free medium for 6 days. Apoptosis was measured at the indicated time points using fluorescence-activated cell sorting (FACS)-based Annexin-V/PI double staining. Results: Compared with normal liver tissue, the expression of PHB in HBV-infected liver tissue was down-regulated (P < 0.01). Compared with HepG2 cells, the expression of PHB in HepG2.2.15 cells was significantly decreased (P < 0.01). The expression level of PHB in liver tissue after antiviral treatment (tenofovir) was significantly higher than that before treatment (P < 0.01). Compared with the control vector, the proliferation rate of HepG2.2.15 cells transfected with Pcmv6-AC-GFP-PHB was significantly lower than that of the control vector, and the apoptosis rate of HepG2.2.15 cells transfected with the Pcmv6-AC-GFP-PHB vector was significantly higher than the control vector (P < 0.01). Conclusion: HBV down-regulates the expression of inhibin to promote the proliferation and survival of hepatocellular carcinoma cells.

Effect of number of lysine motifs on the bactericidal and hemolytic activity of short cationic antimicrobial peptides

Antimicrobial peptides (AMPs) are vital components of the nonspecific immune system that represent a promising broad-spectrum alternative to conventional antibiotics. Several short cationic antimicrobial peptides show highly effective antibacterial activity and low hemolytic activity, which are based on the action of a few critical amino acids, such as phenylalanine (F) and lysine (K). Previous studies have reported that Fmoc-based phenylalanine peptides possess appreciable antibacterial potency against Gram-positive bacteria, but their ability to kill Gram-negative bacteria was suboptimal. In this study, we designed and prepared a series of Fmoc-K_nF peptide (n = 1-3) series by adding lysine motifs to strengthen their broad-spectrum antibacterial activity. The effect was investigated that the amount of lysine in Fmoc-F peptides on their antibacterial properties and hemolytic activities. Our results showed that the Fmoc-KKF peptide holds the strongest antimicrobial activity against both Gram-positive and negative bacteria among all designed peptides, as well as low hemolytic activity. These results provide support for the general strategy of enhancing the broad-spectrum antibacterial activity of AMPs through increased lysine content.

[Genetic analysis of a pregnant woman with moderate intellectual disability due to variant of DLG4 gene]

OBJECTIVE

To carry out genetic testing and prenatal diagnosis for a woman featuring moderate intellectual disability (ID).

METHODS

The patient had presented at the First Affiliated Hospital of Zhengzhou University on April 28, 2021. With informed consent, peripheral blood and amniotic fluid samples were collected for the extraction of genomic DNA. Pathogenic copy number variations (CNVs) were detected with CNV-seq, and single gene variants were detected by whole exome sequencing (WES) and Sanger sequencing. Candidate variant was verified by Sanger sequencing, and CNV-seq and multiplex ligation-dependent probe amplification (MLPA) were used to detect fetal CNVs.

RESULTS

The 23-year-old woman had moderate ID, sideway walking, and unstable holding. Ultrasonography at 18⁺³ weeks' gestation had revealed no fetal abnormality. No pathogenic CNV was detected in the woman by CNV-Seq, while WES revealed that she has harbored a heterozygous c.1675C>T (p.Arg559*) variant of the DLG4 gene, which was verified by Sanger sequencing. Based on guidelines from the American College of Medical Genetics and Genomics, the variant was predicted to be likely pathogenic (PVS1+PM2_supporting). Sanger sequencing has confirmed that the fetus has inherited this variant, and CNV-Seq also revealed that that fetus has harbored a 0.1 Mb heterozygous deletion at Xp21.1, which has encompassed the DMD gene, and the result was verified by MLPA.

CONCLUSION

The heterozygous c.1675C>T variant of the DLG4 gene probably underlay the mental retardation in this woman, and her fetus was found to harbor the same variant in addition with deletion of the DMD gene, which may predispose to ID type 62.

[Analysis of genome copy number variations in fetuses with isolated ventricular septal defect and a literature review]

OBJECTIVE

To assess the value of copy number variation sequencing (CNV-seq) for revealing the genetic etiology of fetuses with isolated ventricular septal defect (VSD).

METHODS

From December 2017 to December 2020, 69 fetuses with isolated VSD were identified at the First Affiliated Hospital of Zhengzhou University. Meanwhile, 839 similar prenatal cases were selected from public databases including Wanfang data, Wanfang Medicine, and China National Knowledge Infrastructure (CNKI) by using keywords such as "Ventricular septal defect", "Copy number variation", and "Prenatal". A total of 908 fetuses with isolated VSD were analyzed. CNV-seq was carried out for 69 fetuses.

RESULTS

Among the 908 fetuses, 33 (3.63%) were found to harbor pathogenic CNVs, which included 11 chromosomal aneuploidies (1.21%) and 22 pathogenic CNVs (2.42%). The pathogenic CNVs have involved 12 genetic syndromes, with those known to involve the heart development including 5 cases of 22q11.21 deletion syndrome, 2 cases of 4q terminal deletion syndrome, and 1 case of 9q subtelomere deletion syndrome. The outcome of pregnancies for 15 fetuses with pathogenic CNVs was known, of which 12 were terminated, and 3 had spontaneous closure of the ventricular septum after birth, but 1 of them had other abnormalities.

CONCLUSION

Fetuses with isolated VSD have a relatively high risk for chromosomal abnormalities, for which CNV-seq should be recommended.

Structural variations and environmental specificities of flowering time-related genes in Brassica napus

We found that the flowering time order of accessions in a genetic population considerably varied across environments, and homolog copies of essential flowering time genes played different roles in different locations. Flowering time plays a critical role in determining the life cycle length, yield, and quality of a crop. However, the allelic polymorphism of flowering time-related genes (FTRGs) in Brassica napus, an important oil crop, remains unclear. Here, we provide high-resolution graphics of FTRGs in B. napus on a pangenome-wide scale based on single nucleotide polymorphism (SNP) and structural variation (SV) analyses. A total of 1337 FTRGs in B. napus were identified by aligning their coding sequences with Arabidopsis orthologs. Overall, 46.07% of FTRGs were core genes and 53.93% were variable genes. Moreover, 1.94%, 0.74%, and 4.49% FTRGs had significant presence-frequency differences (PFDs) between the spring and semi-winter, spring and winter, and winter and semi-winter ecotypes, respectively. SNPs and SVs across 1626 accessions of 39 FTRGs underlying numerous published qualitative trait loci were analyzed. Additionally, to identify FTRGs specific to an eco-condition, genome-wide association studies (GWASs) based on SNP, presence/absence variation (PAV), and SV were performed after growing and observing the flowering time order (FTO) of plants in a collection of 292 accessions at three locations in two successive years. It was discovered that the FTO of plants in a genetic population changed a lot across various environments, and homolog copies of some key FTRGs played different roles in different locations. This study revealed the molecular basis of the genotype-by-environment (G × E) effect on flowering and recommended a pool of candidate genes specific to locations for breeding selection.

Preoperative prediction and histological stratification of intracranial solitary fibrous tumours by machine-learning models

AIM

To explore the effectiveness and feasibility of machine-learning models based on magnetic resonance imaging (MRI) radiomics features in differentiating intracranial solitary fibrous tumour (ISFT) from angiomatous meningioma (AM) and stratifying ISFT histologically.

MATERIALS AND METHODS

This study retrospectively recruited 268 patients with a histological diagnosis of ISFT (n=120) or AM (n=148), and 116 of the ISFT patients were used for stratified analysis of histological grade. The radiomics features were extracted from axial T1-weighted imaging (WI), T2WI and contrast-enhanced T1WI sequences. All patients were assigned randomly to the training group and test group in a ratio of 7:3. The models were optimised by 10-fold cross-validation in the training group, and the independent test group was used for further testing of the models. The performances of machine-learning models based on radiomics, clinical, and fusion features in predicting and stratifying ISFT were evaluated.

RESULTS

ISFT and AM differed significantly in terms of age, tumour shape, enhancement pattern, and margin. There was no significant difference in the clinical characteristics between World Health Organization (WHO) grade II and WHO grade III ISFT. When used to differentiate ISFT from AM, the area under the curve (AUC) values of the machine-learning models based on radiomics, clinical, and fusion features in the test group were 0.917, 0.923 and 0.950, respectively. When used for histological stratification of ISFT, the model based on the radiomics signature achieved an AUC value of 0.786 in the test group.

CONCLUSIONS

Machine-learning models can contribute in the prediction and histological stratification of ISFT non-invasively, which can help clinical differential diagnosis and treatment decisions.

Case report: a Chinese girl like atypical Rubinstein-Taybi syndrome caused by a novel heterozygous mutation of the EP300 gene

BACKGROUND

Rubinstein-Taybi syndrome (RSTS) is an extremely rare autosomal dominant inheritable disorder caused by CREBBP and EP300 mutations, while atypical RSTS harbouring variant from the same genes but not obvious resembling RSTS. There are only a few cases of Menke-Hennekam syndrome (MKHK) with variant of exon 30 or 31 of CREBBP or EP300 gene have been reported that not resembling RSTS recent years. Atypical RSTS cannot be accurately classified as MKHK, nor is it easy to identify the obvious classic characteristics of RSTS. The clinical manifestations and genetic variation of atypical RSTS are not fully understood.

CASE PRESENTATION

We present a Chinese core family with a girl had recurrent respiratory tract infection and developmental delay. The patient with language and motor mild development retardation, she has slight abnormal facial features, mild hirsutism and post-axial hexadactylia of left foot. Her cisterna magna is enlarged to connect with the fourth ventricle, and the ventricular system is enlarged. She has a malacia beside the posterior horn of the left lateral ventricle. The patient has primary low immunoglobulin G and A, but her level of immunoglobulin M content in blood is normal. The patient harbors a novel heterozygous frameshift variant of c.2499dupG in exon 14 of EP300 gene, that it is proved to de novo origin. The mutation is judged to be a pathogenic mutation, and it has high-grade pathogenic evidence.

CONCLUSION

The clinical and genetic evaluation of this case corroborates that clinical features caused by c.2499dupG in exon 14 of EP300 are less marked than RSTS2 patient although it is difficult to establish an accurate genotype-phenotype correlation. Our additional case also helps to deepen the clinical and genetic spectrum in this disorder. The case provides a novel mutation of EP300 and enriches the phenotypes related with the gene. We have contributed new variation and disease information for guardians and doctors to broaden the knowledge about EP300-RSTS genotype and phenotype, this may contribute to ameliorate the health management of patients and improve the genetic counseling to the families.

Whole-exome sequencing in deceased fetuses with ultrasound anomalies: a retrospective analysis

BACKGROUND

Whole-exome sequencing (WES) is an effective method in the prenatal setting for identification of the underlying genetic etiology of fetal ultrasound abnormalities. To investigate the diagnostic value of WES in fetuses with ultrasound abnormalities that resulted in fetal demise or pregnancy termination.

METHODS

61 deceased fetuses with ultrasound abnormalities and normal copy number variation Sequencing were retrospectively collected. Proband-only or trio-WES were performed on the products of conception.

RESULT

Collectively, 28 cases were positive with 39 variants (10 pathogenic, 22 likely pathogenic and 7 variants of uncertain significance) of 18 genes, and the overall diagnostic rate was 45.9% (28/61), of which 39.2% (11/28) were de novo variants. In addition, 21 variants in 11 genes among the positive cases had not been previously reported. The diagnostic yield for definitive findings for trio analysis was 55.9% (19/34) compared to 33.3% (9/27) for singletons. The most common ultrasound abnormalities were skeletal system abnormalities 39.2% (11/28), followed by multiple system abnormalities (17.9%, 5/28) and genitourinary abnormalities (17.9%, 5/28).

CONCLUSION

Our results support the use of WES to identify genetic etiologies of ultrasound abnormalities and improve understanding of pathogenic variants. The identification of disease-related variants provided information for subsequent genetic counseling of recurrence risk and management of subsequent pregnancies.