Non-invasive prediction of preeclampsia using the maternal plasma cell-free DNA profile and clinical risk factors.

Background: Preeclampsia (PE) is a pregnancy complication defined by new onset hypertension and proteinuria or other maternal organ damage after 20 weeks of gestation. Although non-invasive prenatal testing (NIPT) has been widely used to detect fetal chromosomal abnormalities during pregnancy, its performance in combination with maternal risk factors to screen for PE has not been extensively validated. Our aim was to develop and validate classifiers that predict early- or late-onset PE using the maternal plasma cell-free DNA (cfDNA) profile and clinical risk factors. Methods: We retrospectively collected and analyzed NIPT data of 2,727 pregnant women aged 24-45 years from four hospitals in China, which had previously been used to screen for fetal aneuploidy at 12 + 0 ~ 22 + 6 weeks of gestation. According to the diagnostic criteria for PE and the time of diagnosis (34 weeks of gestation), a total of 143 early-, 580 late-onset PE samples and 2,004 healthy controls were included. The wilcoxon rank sum test was used to identify the cfDNA profile for PE prediction. The Fisher's exact test and Mann-Whitney U-test were used to compare categorical and continuous variables of clinical risk factors between PE samples and healthy controls, respectively. Machine learning methods were performed to develop and validate PE classifiers based on the cfDNA profile and clinical risk factors. Results: By using NIPT data to analyze cfDNA coverages in promoter regions, we found the cfDNA profile, which was differential cfDNA coverages in gene promoter regions between PE and healthy controls, could be used to predict early- and late-onset PE. Maternal age, body mass index, parity, past medical histories and method of conception were significantly differential between PE and healthy pregnant women. With a false positive rate of 10%, the classifiers based on the combination of the cfDNA profile and clinical risk factors predicted early- and late-onset PE in four datasets with an average accuracy of 89 and 80% and an average sensitivity of 63 and 48%, respectively. Conclusion: Incorporating cfDNA profiles in classifiers might reduce performance variations in PE models based only on clinical risk factors, potentially expanding the application of NIPT in PE screening in the future.

A developmental validation of the Quick TargSeq 1.0 integrated system for automated DNA genotyping in forensic science for reference samples.

Analysis of short tandem repeats (STRs) is a global standard method for human identification. Insertion/Deletion polymorphisms (DIPs) can be used for biogeographical ancestry inference. Current DNA typing involves a trained forensic worker operating several specialized instruments in a controlled laboratory environment, which takes 6-8 h. We developed the Quick TargSeq 1.0 integrated system (hereinafter abbreviated to Quick TargSeq) for automated generation of STR and DIP profiles from buccal swab samples and blood stains. The system fully integrates the processes of DNA extraction, polymerase chain reaction (PCR) amplification, and electrophoresis separation using microfluidic biochip technology. Internal validation studies were performed using RTyper 21 or DIP 38 chip cartridges with single-source reference samples according to the Scientific Working Group for DNA Analysis Methods guidelines. These results indicated that the Quick TargSeq system can process reference samples and generate STR or DIP profiles in approximately 2 h, and the profiles were concordant with those determined using traditional STR or DIP analysis methods. Thus, reproducible and concordant DNA profiles were obtained from reference samples. Throughout the study, no lane-to-lane or run-to-run contamination was observed. The Quick TargSeq system produced full profiles from buccal swabs with at least eight swipes, dried blood spot cards with two 2-mm disks, or 10 ng of purified DNA. Potential PCR inhibitors (i.e., coffee, smoking tobacco, and chewing tobacco) did not appear to affect the amplification reactions of the instrument. The overall success rate and concordance rate of 153 samples were 94.12% and 93.44%, respectively, which is comparable to other commercially available rapid DNA instruments. A blind test initiated by a DNA expert group showed that the system can correctly produce DNA profiles with 97.29% genotype concordance with standard bench-processing methods, and the profiles can be uploaded into the national DNA database. These results demonstrated that the Quick TargSeq system can rapidly generate reliable DNA profiles in an automated manner and has the potential for use in the field and forensic laboratories.

Population-based screening for colorectal cancer in Wuhan, China.

Fecal DNA test has emerged as a non-invasive alternative for colorectal cancer (CRC) screening in average-risk population. However, there is currently insufficient evidence in China to demonstrate the effectiveness of population-based CRC screening using fecal DNA based test. Here, a large-scale real-world study for CRC screening was implemented in Wuhan, Hubei province, China. A total of 98,683 subjects aged between 45 and 60 years were screened by a fecal DNA test (ColoTect®) which detected methylation status of SDC2, ADHFE1, and PPP2R5C. Participants who tested positive were advised to receive diagnostic colonoscopy. 4449 (4.5%) subjects tested positive for fecal DNA test, and 3200 (71.9%) underwent colonoscopy. Among these, 2347 (73.3%) had abnormal colonoscopy findings, of which 1330 (56.7%) subjects received pathological diagnosis. Detection rates for CRC and advanced precancerous lesions were 1.3% and 2.3%, respectively. Detection rates for nonadvanced adenomas and polyps were 14.0% and 21.6%, respectively. 28.0% of all colonoscopies showed colorectal neoplasm but lack pathological diagnosis. 6.1% showed other abnormalities such as enteritis. In conclusion, preliminary real-world evidence suggested that fecal DNA tests had promising diagnostic yield in population-based CRC screening. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=192838, identifier ChiCTR2300070520.

CHARGE syndrome with early fetal ear abnormalities: A case report.

Key Clinical Message: CHARGE syndrome is a rare genetic disorder characterized by several distinct features. The presence of fetal ear abnormalities could be the early indicator of CHARGE syndrome. Subsequent prenatal diagnosis is essential to confirm the disorder. This is significant because the patient may receive genetic counseling and appropriate disposal based on the accurate diagnosis. Abstract: CHARGE syndrome is a rare genetic disorder with multiple specific clinical features. The prenatal diagnosis is crucial but rarely achieved. We report a fetus with fetal external ear abnormality detected by ultrasound at 22nd week of gestation. Postnatal examination revealed an external ear abnormality, a mild atrial septal defect, and other clinical signs of CHARGE syndrome. A de novo pathogenic nonsense mutation in the CHD7 gene (c.406C > T, p.Q136X in exon 2) was identified to cause the disorder. Our study demonstrated that prenatal diagnosis and genetic testing were recommended to obtain a solid diagnosis of CHARGE syndrome when fetal external ear abnormality was detected by ultrasound examination.

Clinical and genetic architecture of a large cohort with auditory neuropathy.

Auditory neuropathy (AN) is a unique type of language developmental disorder, with no precise rate of genetic contribution that has been deciphered in a large cohort. In a retrospective cohort of 311 patients with AN, pathogenic and likely pathogenic variants of 23 genes were identified in 98 patients (31.5% in 311 patients), and 14 genes were mutated in two or more patients. Among subgroups of patients with AN, the prevalence of pathogenic and likely pathogenic variants was 54.4% and 56.2% in trios and families, while 22.9% in the cases with proband-only; 45.7% and 25.6% in the infant and non-infant group; and 33.7% and 0% in the bilateral and unilateral AN cases. Most of the OTOF gene (96.6%, 28/29) could only be identified in the infant group, while the AIFM1 gene could only be identified in the non-infant group; other genes such as ATP1A3 and OPA1 were identified in both infant and non-infant groups. In conclusion, genes distribution of AN, with the most common genes being OTOF and AIFM1, is totally different from other sensorineural hearing loss. The subgroups with different onset ages showed different genetic spectrums, so did bilateral and unilateral groups and sporadic and familial or trio groups.

Procedural Efficiencies and Clinical Outcomes for Transcatheter Device Closure of Perimembranous Ventricular Septal Defects With Different Waist-Length Occluders.

BACKGROUND: Potential differences in complications and/or long-term outcomes of perimembranous ventricular septal defect (pmVSD) closures with 3-mm waist vs. 4-mm waist double-disk symmetrical occluders are not known.Methods and Results: A total of 395 consecutive pediatric patients with pmVSD recruited between January 2017 and March 2021 underwent successful transcatheter closure using symmetrical pmVSD devices. The final analysis involved 208×3-mm and 172×4-mm cases. The median follow-up was 42 months (range: 12-62 months). A total of 175 post-procedure adverse events (AEs) were observed. Most of these AEs were temporary, and there were only 8 major AEs. Compared to the 3-mm waist group, the incidence of residual shunts was significantly higher in the 4-mm waist group (13.4% vs. 6.7%; P=0.030), whereas other AEs showed similar incidences between the 2 groups. Multivariate Cox regression analysis revealed that larger defect, higher ratio between device size and body surface area, and longer procedure time can cause an increased likelihood of AEs, and smaller defect or left disk placement within aneurysmal tissue may reduce it. CONCLUSIONS: Transcatheter closure of pmVSD using a symmetrical double-disk occluder is safe and effective. Compared with a 3-mm waist symmetrical occluder, transcatheter closure with a 4-mm waist symmetrical occluder correlated with higher incidences of residual shunts.

Single-cell analysis reveals specific neuronal transition during mouse corticogenesis.

Background: Currently, the mechanism(s) underlying corticogenesis is still under characterization. Methods: We curated the most comprehensive single-cell RNA-seq (scRNA-seq) datasets from mouse and human fetal cortexes for data analysis and confirmed the findings with co-immunostaining experiments. Results: By analyzing the developmental trajectories with scRNA-seq datasets in mice, we identified a specific developmental sub-path contributed by a cell-population expressing both deep- and upper-layer neurons (DLNs and ULNs) specific markers, which occurred on E13.5 but was absent in adults. In this cell-population, the percentages of cells expressing DLN and ULN markers decreased and increased, respectively, during the development suggesting direct neuronal transition (namely D-T-U). Whilst genes significantly highly/uniquely expressed in D-T-U cell population were significantly enriched in PTN/MDK signaling pathways related to cell migration. Both findings were further confirmed by co-immunostaining with DLNs, ULNs and D-T-U specific markers across different timepoints. Furthermore, six genes (co-expressed with D-T-U specific markers in mice) showing a potential opposite temporal expression between human and mouse during fetal cortical development were associated with neuronal migration and cognitive functions. In adult prefrontal cortexes (PFC), D-T-U specific genes were expressed in neurons from different layers between humans and mice. Conclusion: Our study characterizes a specific cell population D-T-U showing direct DLNs to ULNs neuronal transition and migration during fetal cortical development in mice. It is potentially associated with the difference of cortical development in humans and mice.

Populational pan-ethnic screening panel enabled by deep whole genome sequencing.

Birth defect is a global threat to the public health systems. Mitigating neonatal anomalies is hampered by elusive molecular mechanisms of pathogenic mutations and poor subsequent translation into preventative measures. Applying appropriate strategies in China to promote reproductive health is particularly challenging, as the Chinese population compromises complex genomic diversity due to the inclusion of many ethnic groups with distinct genetic backgrounds. To investigate and evaluate the feasibility of implementing a pan-ethnic screening strategy, and guide future reproductive counselling, high-quality variants associated with autosome recessive (AR) diseases derived from the largest publicly available cohort of the Chinese population were re-analysed using a bottom-up approach. The analyses of gene carrier rates (GCRs) across distinct ethnic groups revealed that substantial heterogeneity existed potentially due to diverse evolutionary selection. The sampling population, sequencing coverage and underlying population structure contributed to the differential variants observed between ChinaMAP and the East Asian group in gnomAD. Beyond characteristics of GCR, potential druggable targets were additionally explored according to genomic features and functional roles of investigated genes, demonstrating that phase separation could be a therapeutic target for autosomal recessive diseases. A further examination of estimated GCR across ethnic groups indicated that most genes shared by at least two populations could be utilised to direct the design of a pan-ethnic screening application once sequencing and interpreting costs become negligible. To this end, a list of autosomal recessive disease genes is proposed based on the prioritised rank of GCR to formulate a tiered screening strategy.

Noninvasive preeclampsia prediction using plasma cell-free RNA signatures.

BACKGROUND: Preeclampsia, especially preterm preeclampsia and early-onset preeclampsia, is a life-threating pregnancy disorder, and the heterogeneity and complexity of preeclampsia make it difficult to predict risk and to develop treatments. Plasma cell-free RNA carries unique information from human tissue and may be useful for noninvasive monitoring of maternal, placental, and fetal dynamics during pregnancy. OBJECTIVE: This study aimed to investigate various RNA biotypes associated with preeclampsia in plasma and to develop classifiers to predict preterm preeclampsia and early-onset preeclampsia before diagnosis. STUDY DESIGN: We performed a novel, cell-free RNA sequencing method termed polyadenylation ligation-mediated sequencing to investigate the cell-free RNA characteristics of 715 healthy pregnancies and 202 pregnancies affected by preeclampsia before symptom onset. We explored differences in the abundance of different RNA biotypes in plasma between healthy and preeclampsia samples and built preterm preeclampsia and early-onset preeclampsia prediction classifiers using machine learning methods. Furthermore, we validated the performance of the classifiers using the external and internal validation cohorts and assessed the area under the curve and positive predictive value. RESULTS: We detected 77 genes, including messenger RNA (44%) and microRNA (26%), that were differentially expressed in healthy mothers and mothers with preterm preeclampsia before symptom onset, which could separate participants with preterm preeclampsia from healthy samples and that played critical functional roles in preeclampsia physiology. We developed 2 classifiers for predicting preterm preeclampsia and early-onset preeclampsia before diagnosis based on 13 cell-free RNA signatures and 2 clinical features (in vitro fertilization and mean arterial pressure), respectively. Notably, both classifiers showed enhanced performance when compared with the existing methods. The preterm preeclampsia prediction model achieved 81% area under the curve and 68% positive predictive value in an independent validation cohort (preterm, n=46; control, n=151); the early-onset preeclampsia prediction model had an area under the curve of 88% and a positive predictive value of 73% in an external validation cohort (early-onset preeclampsia, n=28; control, n=234). Furthermore, we demonstrated that downregulation of microRNAs may play vital roles in preeclampsia through the upregulation of preeclampsia-relevant target genes. CONCLUSION: In this cohort study, a comprehensive transcriptomic landscape of different RNA biotypes in preeclampsia was presented and 2 advanced classifiers with substantial clinical importance for preterm preeclampsia and early-onset preeclampsia prediction before symptom onset were developed. We demonstrated that messenger RNA, microRNA, and long noncoding RNA can simultaneously serve as potential biomarkers of preeclampsia, holding the promise of prevention of preeclampsia in the future. Abnormal cell-free messenger RNA, microRNA, and long noncoding RNA molecular changes may help to elucidate the pathogenic determinants of preeclampsia and open new therapeutic windows to effectively reduce pregnancy complications and fetal morbidity.

The Frequency of Common Deafness-Associated Variants Among 3,555,336 Newborns in China and 141,456 Individuals Across Seven Populations Worldwide.

OBJECTIVES: Genetic screening can benefit early detection and intervention for hearing loss. The frequency of common deafness-associated variants in general populations is highly important for genetic screening and genetic counseling tailored to different ethnic backgrounds. We aimed to analyze the frequency of common deafness-associated variants in a large population-based Chinese newborn cohort and to explore the population-specific features in diverse populations worldwide. DESIGN: This population-based cohort study analyzed the frequency of common deafness-associated variants in 3,555,336 newborns in the Chinese Newborn Concurrent Hearing and Genetic Screening cohort. Participants were newborn infants born between January 2007 and September 2020. Limited genetic screening for 20 variants in 4 common deafness-associated genes and newborn hearing screening were offered concurrently to all newborns in the Chinese Newborn Concurrent Hearing and Genetic Screening cohort. Sequence information of 141,456 individuals was also analyzed from seven ethnic populations from the Genome Aggregation Database for 20 common deafness-related variants. Statistical analysis was performed using R. RESULTS: A total of 3,555,326 Chinese neonates completed the Newborn Concurrent Hearing and Genetic Screening were included for analysis. We reported the distinct landscape of common deafness-associated variants in this large population-based cohort. We found that the carrier frequencies of GJB2 , SLC26A4 , GJB3 , and MT-RNR were 2.53%, 2.05%, 0.37%, and 0.25%, respectively. Furthermore, GJB2 c.235delC was the most common variant with an allele frequency of 0.99% in the Chinese newborn population. We also demonstrated nine East-Asia-enriched variants, one Ashkenazi Jewish-enriched variant, and one European/American-enriched variant for hearing loss. CONCLUSIONS: We showed the distinct landscape of common deafness-associated variants in the Chinese newborn population and provided insights into population-specific features in diverse populations. These data can serve as a powerful resource for otolaryngologists and clinical geneticists to inform population-adjusted genetic screening programs for hearing loss.

Identify gestational diabetes mellitus by deep learning model from cell-free DNA at the early gestation stage.

Gestational diabetes mellitus (GDM) is a common complication of pregnancy, which has significant adverse effects on both the mother and fetus. The incidence of GDM is increasing globally, and early diagnosis is critical for timely treatment and reducing the risk of poor pregnancy outcomes. GDM is usually diagnosed and detected after 24 weeks of gestation, while complications due to GDM can occur much earlier. Copy number variations (CNVs) can be a possible biomarker for GDM diagnosis and screening in the early gestation stage. In this study, we proposed a machine-learning method to screen GDM in the early stage of gestation using cell-free DNA (cfDNA) sequencing data from maternal plasma. Five thousand and eighty-five patients from north regions of Mainland China, including 1942 GDM, were recruited. A non-overlapping sliding window method was applied for CNV coverage screening on low-coverage (~0.2×) sequencing data. The CNV coverage was fed to a convolutional neural network with attention architecture for the binary classification. The model achieved a classification accuracy of 88.14%, precision of 84.07%, recall of 93.04%, F1-score of 88.33% and AUC of 96.49%. The model identified 2190 genes associated with GDM, including DEFA1, DEFA3 and DEFB1. The enriched gene ontology (GO) terms and KEGG pathways showed that many identified genes are associated with diabetes-related pathways. Our study demonstrates the feasibility of using cfDNA sequencing data and machine-learning methods for early diagnosis of GDM, which may aid in early intervention and prevention of adverse pregnancy outcomes.

[Health economic considerations of genetic disease screening - take Down syndrome as an example].

The ongoing development of high-throughput sequencing technology and continuous decline of sequencing cost have made it possible to carry out large-scale screening for genetic diseases, which are the main component of birth defects. The screening of genetic diseases is expected to significantly reduce the rate of birth defects and the burden of genetic diseases to the affected families and the society. Taking Down syndrome as an example, through the analysis of the cost-benefit ratio of relevant screening programs, this article has summarized the socio-economic indicators to be considered during the design and development of genetic disease screening.

Non-Invasive Prenatal Diagnosis of Monogenic Disorders Through Bayesian- and Haplotype-Based Prediction of Fetal Genotype.

Background: Non-invasive prenatal diagnosis (NIPD) can identify monogenic diseases early during pregnancy with negligible risk to fetus or mother, but the haplotyping methods involved sometimes cannot infer parental inheritance at heterozygous maternal or paternal loci or at loci for which haplotype or genome phasing data are missing. This study was performed to establish a method that can effectively recover the whole fetal genome using maternal plasma cell-free DNA (cfDNA) and parental genomic DNA sequencing data, and validate the method's effectiveness in noninvasively detecting single nucleotide variations (SNVs), insertions and deletions (indels). Methods: A Bayesian model was developed to determine fetal genotypes using the plasma cfDNA and parental genomic DNA from five couples of healthy pregnancy. The Bayesian model was further integrated with a haplotype-based method to improve the inference accuracy of fetal genome and prediction outcomes of fetal genotypes. Five pregnancies with high risks of monogenic diseases were used to validate the effectiveness of this haplotype-assisted Bayesian approach for noninvasively detecting indels and pathogenic SNVs in fetus. Results: Analysis of healthy fetuses led to the following accuracies of prediction: maternal homozygous and paternal heterozygous loci, 96.2 ± 5.8%; maternal heterozygous and paternal homozygous loci, 96.2 ± 1.4%; and maternal heterozygous and paternal heterozygous loci, 87.2 ± 4.7%. The respective accuracies of predicting insertions and deletions at these types of loci were 94.6 ± 1.9%, 80.2 ± 4.3%, and 79.3 ± 3.3%. This approach detected pathogenic single nucleotide variations and deletions with an accuracy of 87.5% in five fetuses with monogenic diseases. Conclusions: This approach was more accurate than methods based only on Bayesian inference. Our method may pave the way to accurate and reliable NIPD.

Clinical Profile and Risk Factors for Cardiac Death in Pediatric Patients With Primary Dilated Cardiomyopathy at a Tertiary Medical Center in China.

Aim: We sought to identify the clinical characteristics and risk factors for cardiac mortality in pediatric patients with primary dilated cardiomyopathy (DCM) in China. Methods: A total of 138 pediatric patients who were consecutively diagnosed with primary DCM from January 2011 to December 2020 were included. We assessed patients' clinical symptoms and performed laboratory examinations, electrocardiography, and echocardiography. Results: Of these patients, 79 (57%) had severe systolic dysfunction (left ventricular ejection fraction of < 30%), 79 (57.2%) developed DCM before 12 months of age, 62 (45%) were male, 121 (87.7%) presented with advanced heart failure (cardiac functional class III/IV), and 54 (39.1%) presented with arrhythmia. At a median follow-up of 12 months, the overall cardiac mortality rate was 33%, and 40 of 46 deaths occurred within 6 months following DCM diagnosis. A multivariate Cox regression analysis identified several independent cardiac death predictors, including an age of 12 months to 5 years [hazard ratio (HR) 2.799; 95% confidence interval (CI) 1.160-6.758; P = 0.022] or 10-15 years (HR 3.617; 95% CI 1.336-9.788; P = 0.011) at diagnosis, an elevated serum alanine aminotransferase (ALT) concentration (≥ 51.5 U/L) (HR 2.219; 95% CI 1.06-4.574; P = 0.031), and use of mechanical ventilation (HR 4.223; 95% CI 1.763-10.114; P = 0.001). Conclusion: The mortality rate of primary DCM without transplantation is high. Age, an elevated serum ALT concentration, and the need for mechanical ventilation predict mortality in patients with primary DCM, providing new insights into DCM risk stratification.

A Comprehensive Survey of Genomic Mutations in Breast Cancer Reveals Recurrent Neoantigens as Potential Therapeutic Targets.

Neoantigens are mutated antigens specifically generated by cancer cells but absent in normal cells. With high specificity and immunogenicity, neoantigens are considered as an ideal target for immunotherapy. This study was aimed to investigate the signature of neoantigens in breast cancer. Somatic mutations, including SNVs and indels, were obtained from cBioPortal of 5991 breast cancer patients. 738 non-silent somatic variants present in at least 3 patients for neoantigen prediction were selected. PIK3CA (38%), the highly mutated gene in breast cancer, could produce the highest number of neoantigens per gene. Some pan-cancer hotspot mutations, such as PIK3CA E545K (6.93%), could be recognized by at least one HLA molecule. Since there are more SNVs than indels in breast cancer, SNVs are the major source of neoantigens. Patients with hormone receptor-positive or HER2 negative are more competent to produce neoantigens. Age, but not the clinical stage, is a significant contributory factor of neoantigen production. We believe a detailed description of breast cancer neoantigen signatures could contribute to neoantigen-based immunotherapy development.

Electrocardiographic Characteristics and Catheter Ablation of Ventricular Arrhythmias Originating From the Moderator Band in Children.

AIMS: To investigate the electrocardiographic (ECG) characteristics and catheter ablation of ventricular arrhythmias (VAs) originating from the moderator band (MB) in children. METHODS: A total of six children who had VAs originating from the MB-as confirmed by electrophysiological study-and who underwent catheter ablation between January 2016 and December 2020 were retrospectively reviewed. During the procedure, a three-dimensional electroanatomic mapping system was used to facilitate three-dimensional anatomical reconstruction, mapping and ablation. Patients' clinical characteristics, ECG features and procedural data were collected and analyzed. RESULTS: The mean age was 8.4 ± 2.6 years (range: 5.3-11 years) and mean weight was 27.7 ± 11.4 kg (range: 17-47 kg). Four patients presented with frequent premature ventricular contraction (PVC), one patient presented with frequent PVC and non-sustained ventricular tachycardia, and one patient presented with sustained monomorphic ventricular tachycardia. The QRS duration averaged 126.3 ± 4.6 ms. In all patients, the VAs had left bundle branch block QRS with left superior frontal plane axes, rapid downstrokes of the QRS in the precordial leads, and late precordial transitions (>V4). During the same period, 10 cases of VAs originated from the posterior-lateral wall of the tricuspid annulus, with a mean QRS duration of 152.8 ± 6.4 ms. Compared to that, VAs of MB origin have narrower QRS widths, downstroke slopes in the inferior lead, sharper downstroke slopes in the precordial lead, and smaller R-wave amplitudes in the V6 lead. All patients experienced immediate ablation success with activations earlier than QRS by 26.0 ± 3.5 ms, and no procedural complications occurring. Only one case had recurrent PVC during a follow-up period ranging from 6 to 36 months. CONCLUSION: MB VAs in children have distinctive ECG morphology and electrophysiological characteristics. Catheter ablation using a three-dimensional electroanatomic mapping system is safe and effective in these patients.

Next-Generation Sequencing Reveals Novel Genetic Variants for Dilated Cardiomyopathy in Pediatric Chinese Patients.

Dilated cardiomyopathy (DCM) is a myocardial disease characterized by bilateral or left ventricular cardiac dilation and systolic dysfunction that can lead to heart failure and sudden cardiac death in children. Many studies have focused on genetic variation in DCM-related genes in adult populations; however, the mutational landscape in pediatric DCM patients remains undetermined, especially in the Chinese population. We applied next-generation sequencing (NGS) technology to genetically analyze 46 pediatric DCM patients to reveal genotype-phenotype correlations. Our results indicated DCM-associated pathogenic mutations in 10 genes related to the structure or function of the sarcomere, desmosome, and cytoskeleton. We also identified 6 pathogenic mutations (5 novel) in the Titin (TTN) gene that resulted in truncated TTN variants in 6 (13%) out of 46 patients. Correlations between TTN mutations and clinical outcomes were assessed. Our data indicate that one-third of pediatric DCM cases are caused by genetic mutations. The role of TTN variants should not be underestimated in pediatric DCM and age-dependent pathogenic penetrance of these mutations should be considered for familial DCM cases. We argue that genetic testing of DCM cases is valuable for predicting disease severity, prognosis, and recurrence risk, and for screening first-degree relatives.

Oligonucleotide aptamers: Recent advances in their screening, molecular conformation and therapeutic applications.

Aptamers are single stranded oligonucleotides with specific recognition and binding ability to target molecules, which can be obtained by Systematic Evolution of Ligands by Exponential Enrichment (SELEX). Aptamers have the advantages of low molecular weight, low immunogenicity, easy modification and high stability. They play promising role in promoting food safety, monitoring the environment and basic research, especially in clinical diagnosis and therapeutic drugs. To date, great achievements regarding the selection, modifications and application of aptamers have been made. However, since it is still a challenge to obtain aptamers with high affinity in a more effective way, few aptamer-based products have already successfully entered into clinical use. This review aims to provide a thorough overview of the latest advances in this rapidly developing field, focusing on aptamer screening methods for different targets, the structure of the interaction between aptamers and target substances, and the challenges and potential of current therapeutic aptamers.

Evaluation of biochar addition and circulation control strengthening measures on efficiency and microecology of food waste treatment in anaerobic reactor.

The process of strengthening an expanded granular sludge blanket (EGSB) reactor under ammonia nitrogen stress conditions and by adopting three strengthening measures, namely, opening the circulation (OC), adding modified biochar (MB), adding modified biochar along with opening the circulation (MBOC), to treat food waste was studied. When the ammonia nitrogen concentration of influent increased to 1200 mg/L, the removal rate of COD reduced to about 75%, while the removal rate of ammonia nitrogen was about 6%. The average COD removal rate of the anaerobic reactor in the last 5 days of each operating cycle i.e. OC, MB and MBOC, was 85.51%, 84.11% and 90.03%, respectively. At the 30th day of each treatment-OC, MB and MBOC, the protease content in the sludge was 44.61, 42.47, 46.24 NH2-N (mg)/mg, respectively. and the content of coenzyme F420 was 0.244, 0.217 and 0.267 mmol/g, respectively. Proteobacteria was the most abundant phylum in the stage I (OC), reaching 34.36%. It was accounted for 16.68% and 21.38%, respectively, in the stage II (MB) and stage III (MBOC). The dominant archaea in the three stages were Methanosaeta, whose abundance was 38.98% in stage I, which increased to 64.94% and 64.01% in stage II and III, respectively. Among the active carbohydrate enzymes, the gene abundance of Glycoside transferases in the MBOC stage was the largest among the three stages.

The Efficacy and Medium to Long-Term Follow-Up of Transcatheter Retrograde Closure of Perimembranous Ventricular Septal Defects via the Femoral Artery With Amplatzer Duct Occluder II in Children.

Objective: The aim of this study was to assess the efficacy and safety of transcatheter retrograde closure of perimembranous ventricular septal defect (pmVSD) via the femoral artery with an Amplatzer Duct Occluder II (ADO II) in children. Methods: The clinical and follow-up data of 102 children who had successfully undergone transcatheter retrograde closure of pmVSD via the femoral artery with Amplatzer Duct Occluder II (ADO II) from February 2012 to June 2019 in our center were retrospectively reviewed. Results: In 102 of 103 patients, the defects were successfully closed (99.0%). The average age was 4.03 ± 1.84 years and the mean weight was 17.50 ± 5.58 kg. The mean diameter of the defects was 2.58 ± 0.63 mm. Hundred of the occluders had a waist length of 4 mm. The complete closure rate was 89.2% 24 h after the procedure and 98% at the last follow-up. The follow-up period ranged from 6 to 92 months, with a median of 36 months. One child developed new mild aortic regurgitation (AR), and 9 patients developed new mild tricuspid regurgitation (TR). During follow-up, TR disappeared in 5 patients and decreased in 4 patients, and AR relieved in one patient. One patient developed intermittent complete left bundle branch block 4 days after the procedure and recovered sinus rhythm 2 days later. No serious complications occurred. Conclusion: Transcatheter retrograde closure of pmVSD via the femoral artery with ADO II in children is safe, feasible, and effective in selected patients.