Objective:To investigate the significance of abnormal morphology of Sylvian fissure detected by fetal neurosonogram (NSG) in prenatal diagnosis of malformations of cortical development (MCD).Methods:This retrospective study involved fetuses with abnormal morphology of Sylvian fissure on prenatal NSG in Peking University First Hospital between January 2016 and December 2021. Clinical data including the basic information as well as the results of NSG, genetic examinations and MRI were collected. The diagnosis of MCD could be made when both brain morphological abnormalities and pathogenic/likely pathogenic genetic abnormalities were presented. The association between the abnormal morphology of Sylvian fissure and MCD was analyzed by descriptive analysis.Results:Thirteen participants who had complete genetic information were included in this study [defined as those who were found with pathogenic/likely pathogenic copy number variation (CNV) or those who further underwent whole-exome sequencing (WES) as no pathogenic/likely pathogenic CNV were detected]. Twelve fetuses (12/13) were eventually diagnosed with MCD. Pathogenic CNV were found in seven fetuses and pathogenic point mutations in five, involving six pathogenic genes and four genetic syndromes. Symmetric morphologic abnormality of Sylvian fissure was detected in 10 cases by prenatal NSG with shallow and broad shape in six and abnormal angle of Sylvian fissure in four. The other two fetuses showed asymmetric abnormal morphology of Sylvian fissure that was shallow and broad shape on one side and abnormal angle on the other. The imaging features of MCD present by prenatal NSG and were consistent with those of MRI.Conclusions:Abnormal morphology of Sylvian fissure detected by prenatal NSG is important in MCD diagnosis. Genetic examination are recommended to the fetuses with abnormal morphology of Sylvian fissure. For those requiring for genetic analysis, chromosomal microarray analysis together with WES might be an optimal choice.

Global developmental delay/intellectual disability (GDD/ID) is an enormous group of neurodevelopmental disorders with diverse clinical and genetic heterogeneity. The estimated prevalence of GDD/ID was 1%-3%, affecting about 150 million people. GDD/ID is one of the leading causes of disability in children worldwide. The causes of GDD/ID are complex, comprising genetic and environmental factors. It is often co-morbid with a variety of psychiatric behavioral disorders, such as autism spectrum disorder and attention deficit hyperactivity disorder. Owing to the improvement of genetic technology, monogenic GDD/ID has been one of the hot-spot research in genomic era, and the relevant preventive measures deserve extensive attention. In this review, we summarized the advances in genetics and prevention of monogenic GDD/ID.

Objective:To investigate the correlation between vitamin D deficiency and the severity of symptoms in children with vasovagal syncope (VVS).Methods:A prospective study was conducted. One hundred and twenty-two children diagnosed with VVS by head up tilt test in Department of Pediatric Cardiology and 130 healthy children without symptoms who underwent physical examination in the outpatient department of Child Healthcare Department of Second Hospital of Lanzhou University from December 2019 to May 2021 were selected and assigned to VVS group and control group, respectively. According to the diagnostic criteria of vitamin D deficiency, children in the VVS group were assigned to three subgroups: non-vitamin D deficiency, vitamin D deficiency, and severe vitamin D deficiency. All children underwent detailed history taking, physical examination, and level determination of serum 25 (OH) D. Children in the VVS group were scored for orthostatic intolerance (OI) symptoms including 10 symptoms: syncope, dizziness, nausea, palpitation, headache, tremor, chest tightness, blurred vision, profuse perspiration, and attention deficit. The differences in the age, gender, body mass index, blood pressure, and serum 25 (OH) D levels between VVS group and control group, and the differences regarding the age, gender, body mass index, blood pressure, serum 25 (OH) D levels and symptom scores among the three VVS subgroups were compared. Comparisons were performed using independent sample t test, ANOVA analysis, Chi square test and rank sum test. Pearson correlation analysis was used to analyze the correlation between serum 25 (OH) D levels and OI symptom scores in children with VVS. Results:The serum 25 (OH) D levels were significantly lower in the VVS group than those in the control group ((31±11) vs. (46±10) nmol/L, t=10.89, P<0.001). Vitamin D deficiency was more frequent in the VVS group (73.0% (89/122) vs. 24.6% (32/130), χ2=58.91, P<0.001). There were significant differences among the severe vitamin D deficiency subgroup, vitamin D deficiency subgroup, and non-vitamin D deficiency subgroup regarding the serum 25 (OH) D levels ((9.8±0.4) vs. (26.6±6.5) vs. (45.8±5.9) nmol/L, F=142.77, P<0.001) and the OI symptom scores ((14±1) vs. (10±2) vs. (7±2) scores, F=44.97, P<0.001). The scores of syncope, nausea, profuse perspiration, blurred vision and dizziness among the severe vitamin D deficiency subgroup, vitamin D deficiency subgroup, and non-vitamin D deficiency subgroup were statistically significant ( H=9.01, 7.52, 12.11, 7.07 and 9.54, respectively, all P<0.05). Pearson correlation analysis showed that the serum 25 (OH) D levels were negatively correlated with OI symptom scores in children with VVS ( r=-0.769, P<0.001). Conclusions:VVS children have significant vitamin D deficiency. The severity of symptoms increases with decreasing of vitamin D level. Syncope, nausea, and profuse perspiration are more likely to occur in children with severe vitamin D deficiency, and dizziness and blurred vision are more likely to occur in children with vitamin D deficiency.

Objective:To explore the role of parental origin verification in chromosomal microarray analysis (CMA) on the determination of the clinical significance of copy number variations (CNVs).Methods:This retrospective study collected clinical information from 73 core families who underwent prenatal diagnosis at Peking University First Hospital from November 2017 to December 2019. Indications for prenatal diagnosis included ultrasound abnormality in 54 cases (including 12 with thickened nuchal translucency (≥2.5 mm), four with fetal growth restriction, seven with abnormal pregnancy history, and 31 with isolated ultrasound abnormality), NIPT indicated high-risk in four cases, advanced age in nine cases, abnormal pregnancy history alone in three cases, intrauterine death in two cases and one with maternal mental retardation. Genomic DNA of amniotic fluid sample, chorionic villi, cord blood, fetal tissues, and fetal heart blood were extracted using genomic DNA extraction kit. The CNVs of prenatal samples in 73 subjects were analyzed using array-based comparative genomic hybridization (array-CGH) analysis and single nucleotide polymorphism array (SNP-array). Peripheral blood DNA of the couples, and relevant families if necessary, were collected and analyzed in the same way. The results of parental origin detection in CMA were summarized.Results:A total of 76 CNVs were detected in these 73 samples, out of which nine were pathogenic and parental origin detection revealed that six were de novo, two were maternally, and one was paternally inherited; six CNVs were likely pathogenic, including three de novo, two maternally inherited and one paternally inherited; 20 CNVs were variants of uncertain significance, including five paternally inherited, three maternally inherited and 12 de novo; 41 CNVs were likely benign, among which 38 were inherited from parents with normal phenotype. Conclusions:Parental origin verification plays an important role in explaining the clinical significance of detected fetal CNVs and thereby can help to analyze its clinical effect and reproductive risk.

Objective:To summarize the prenatal diagnostic characteristics of monogenic global developmental delay/intellectual disability(GDD/ID) pedigrees.Methods:This study retrospectively collected the prenatal molecular diagnostic results of 43 pedigrees that were affected with monogenic GDD/ID in the genetic counseling clinic of Peking University First Hospital from January 2015 to June 2019. The results of prenatal molecular tests were validated after birth or pregnancy termination. Pregnancy outcomes and healthy condition of the offspring were followed up. All data were analyzed by descriptive statistical analysis.Results:Among the 43 pedigrees, 24 were affected with autosomal recessive inheritance (AR) GDD/ID, in which six (25%) fetuses were found to carry two pathogenic variants; 13 (55%) had only one pathogenic variant; five (20%) did not harbor any variant. GDD/ID inherited in an autosomal dominant inheritance (AD) pattern was found in 13 pedigrees, in which 11 fetuses carried no variants while the other two fetuses had the same variants as the proband had (in one pedigree, a low-level variant was detected in the peripheral blood sample of the father while absent in peripheral blood samples of parents in the other pedigree, so it was suspected that the variants of these two affected fetuses were inherited from parental mosaicism). In the other six pedigrees with X-linked inheritance (XL) of GDD/ID, one male fetus was found to harbor the pathogenic variant, while no variants were detected in the others. Maternal contamination was excluded in all prenatal samples using short tandem repeat for linkage analysis. Postnatal validations were consistent with the prenatal tests. All nine affected fetuses were terminated, and the other thirty-four children were delivered and in good health.Conclusions:Prenatal molecular diagnostic test is an effective method to detect pathogenic variants during the first and second trimesters for pedigrees affected by monogenic GDD/ID. For pedigrees affected with AD or XL patterns caused by de novo mutations, potential parental mosaicism should be noted and prenatal diagnostic tests are also recommended.

Objective:To summarize the characteristics of genetic variation and prenatal diagnosis in pedigrees with X-linked adrenoleukodystrophy (X-ALD) and elucidate the value of prenatal diagnosis in preventing the birth of children with X-ALD.Methods:Twenty pedigrees, clinically diagnosed with X-ALD in Peking University First Hospital from November 2012 and March 2019, were included in this retrospective study. Genomic DNA was extracted from peripheral blood and amniotic fluid or chorionic villi samples of probands and their families for detecting variants in ATP-binding cassette subfamily D member 1 ( ABCD1) gene using polymerase chain reaction (PCR)-Sanger sequencing. Linkage analysis was also performed on five microsatellite markers near ABCD1 gene to exclude maternal contamination. Characteristics of ABCD1 gene variants and prenatal diagnosis of X-ALD pedigrees were summarized by descriptive statistics. Results:Twenty ABCD1 gene variants were identified in the 20 pedigrees. The variants in three probands that were not detected by next-generation sequencing were identified by PCR-Sanger sequencing. Among the mothers of the 20 probands, 17 carried ABCD1 variants and three did not. We performed 24 prenatal diagnoses on 20 pregnancies (24 fetuses) and identified eight fetuses with variants who were finally terminated. The 16 cases without variants were born alive. The validation results obtained after termination or delivery were consistent with those performed prenatally. Conclusions:No hotspot variants in ABCD1 gene are detected in these X-ALD patients and most variants are maternally inherited. PCR-Sanger sequencing is an effective method for detecting ABCD1 variants. Prenatal diagnosis for mothers who had a body with X-ALD could prevent another one from birth.

Objective:To establish a new bile duct injury and repair model in mice by generating bile duct distal stricture and proximal dilatation.Methods:The mice were randomly divided into sham operation group, bile duct stricture (BDS) group and bile duct ligation (BDL) group. The dilated bile duct of BDS mice was injured and then repaired 14 days after the modeling operation. Biochemical markers were detected and histopathological changes were analyzed.Results:14 days after the establishment of the model, the body mass in BDL group was significantly lower than that of the sham group ( P<0.05), while the body mass in BDS group was similar to sham group. Compared with the sham group, the bile duct and gallbladder of the BDS group and BDL group were both prominently dilated, but the sum of the diameters of bile duct and gallbladder in BDS group was significantly smaller than that in the BDL group ( P<0.05). Indocyanine green fluorescence imaging confirmed that biliary tract of BDS group could still drain bile. Serum ALT, AST and TBil levels in the BDS group were slightly higher than those in the sham group (all P<0.05), but significantly lower than those in the BDL group ( P<0.05). Bile ducts of BDS mice were injured by notching and repaired with bile duct path. 30 days after the repairing, HE staining showed that the bile duct epithelium around the patch was arranged in orderliness. Immunohistochemistry confirmed the positive staining of green fluorescent protein (EGFP) and CK19 in those groups. Conclusion:This model of bile duct injury and repair in mice can provide a new model for the study of the mechanism of bile duct injury and repair and the evaluation of tissue engineering bile duct.

In the original publication, the label of Fig. 2C should be read as "GFAP/lectin/DAPI" not "DMP1/GFAP/lectin/DAPI".

The blood-brain barrier (BBB) is a tight boundary formed between endothelial cells and astrocytes, which separates and protects brain from most pathogens as well as neural toxins in circulation. However, detailed molecular players involved in formation of BBB are not completely known. Dentin matrix protein 1 (DMP1)-proteoglycan (PG), which is known to be involved in mineralization of bones and dentin, is also expressed in soft tissues including brain with unknown functions. In the present study, we reported that DMP1-PG was expressed in brain astrocytes and enriched in BBB units. The only glycosylation site of DMP1 is serine89 (S89) in the N-terminal domain of the protein in mouse. Mutant mice with DMP1 point mutations changing S89 to glycine (S89G), which completely eradicated glycosylation of the protein, demonstrated severe BBB disruption. Another breed of DMP1 mutant mice, which lacked the C-terminal domain of DMP1, manifested normal BBB function. The polarity of S89G-DMP1 astrocytes was disrupted and cell-cell adhesion was loosened. Through a battery of analyses, we found that DMP1 glycosylation was critically required for astrocyte maturation both in vitro and in vivo. S89G-DMP1 mutant astrocytes failed to express aquaporin 4 and had reduced laminin and ZO1 expression, which resulted in disruption of BBB. Interestingly, overexpression of wild-type DMP1-PG in mouse brain driven by the nestin promoter elevated laminin and ZO1 expression beyond wild type levels and could effectively resisted intravenous mannitol-induced BBB reversible opening. Taken together, our study not only revealed a novel element, i.e., DMP1-PG, that regulated BBB formation, but also assigned a new function to DMP1-PG.
Animals ; Astrocytes ; cytology ; metabolism ; Blood-Brain Barrier ; cytology ; metabolism ; Cells, Cultured ; Extracellular Matrix Proteins ; genetics ; metabolism ; Female ; Glycosylation ; Male ; Mice ; Proteoglycans ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction