Hemizygous splicing variant in CNKSR2 results in X-linked intellectual developmental disorder.

BACKGROUND: Intellectual disability (ID) refers to a childhood-onset neurodevelopmental disorder with a prevalence of approximately 1%-3%. METHODS: We performed whole exome sequencing for the patient with ID. And the splicing variant we found was validated by minigene assay. RESULTS: Here, we report a boy with ID caused by a variant of CNKSR2. His neurological examination revealed hypsarrhythmia via electroencephalography and a right temporal polar arachnoid cyst via brain magnetic resonance imaging. A novel splicing variant in the CNKSR2 gene (NM_014927.5, c.1657+1G>A) was discovered by exome sequencing. The variant caused a 166 bp intron retention between exons 14 and 15, which was validated by a minigene assay. The variant was not reported in public databases such as gnomAD and the Exome Aggregation Consortium. CONCLUSIONS: The variant was predicted to be damaging to correct the translation of the CNKRS2 protein and was classified as likely pathogenic according to the ACMG guidelines.

Video-based evaluation system for tic action in Tourette syndrome: modeling, detection, and evaluation.

Behavioral ratings based on clinical observations are still the gold standard for screening, diagnosing, and assessing outcomes in Tourette syndrome. Detecting tic symptoms plays an important role in patient treatment and evaluation; accurate tic identification is the key to clinical diagnosis and evaluation. In this study, we proposed a tic action detection method using face video feature recognition for tic and control groups. Through facial ROI extraction, a 3D convolutional neural network was used to learn video feature representations, and multi-instance learning anomaly detection strategy was integrated to construct the tic action analysis and discrimination framework. We applied this tic recognition framework in our video dataset. The model evaluation results achieved average tic detection accuracy of 91.02%, precision of 77.07% and recall of 78.78%. And the tic score curve with postprocessing provided information of how the patient's twitches change over time. The detection results at the individual level indicated that our method can effectively detect tic actions in videos of Tourette patients without the need for fine labeling, which is significant for the long-term evaluation of patients with Tourette syndrome.

A Heterozygous Variant of FGF13 Caused X-Linked Developmental and Epileptic Encephalopathy 90 in a Chinese Family.

Developmental and epileptic encephalopathy (DEE) refers to a group of severe epilepsy encephalopathy and development disorders, and its typical clinical features include seizures, drug resistance, and developmental delay or regression. To date, limited studies have reported DEEs driven by FGF13. Here, we reported a girl with developmental and epileptic encephalopathy 90 caused by variant of FGF13. Her electroencephalogram (EEG) showed discontinuous hypsarrhythmia, and a heterozygous nonsynonymous variant in FGF13 [NM_004114.4: c.5C>G, p.(Ala2Gly)] was identified from the proband. The variant was not reported in public databases such as gnomAD and Exome Aggregation Consortium (ExAC), and was predicted to be damaging to proteins and classified as likely pathogenic according to the ACMG guidelines. The seizure was finally controlled by a combination of ACTH + zonisamide (10 mg/kg.d) + levetiracetam (52 mg/kg.d) + clonazepam (0.7 mg/kg.d).

Generation of a human iPSC line (ZJSHDPi001-A) from peripheral blood mononuclear cells of a patient with Developmental epileptic encephalopathy-47 carrying FGF12 gene mutation (c.334G > A).

Developmental epileptic encephalopathy-47 (DEE47) is a nervous system disease characterized by the onset of intractable seizures that appear the first days or weeks after birth. FGF12 is the disease-causing gene of DEE47 that encodes a small cytoplasm protein, which is a member of the fibroblast growth factor homologous factor (FGF) family. The FGF12-encoded protein interacts with the cytoplasmic tail of voltage-gated sodium channels to enhance the voltage dependence of rapid inactivation of sodium channels in neurons. This study used non-insertion Sendai virus transfection to establish the induced pluripotent stem cells(iPSCs)line with FGF12 mutation. The cell line was obtained from a 3-year-old boy carrying the c.334G > A heterozygous mutation in the FGF12 gene. This iPSC line could facilitate the investigations of pathogeneses of complex nervous system diseases such as developmental epileptic encephalopathy.

Appetizer on soft matter physics concepts in mechanobiology.

Mechanosensing, the active responses of cells to the mechanics on multiple scales, plays an indispensable role in regulating cell behaviors and determining the fate of biological entities such as tissues and organs. Here, I aim to give a pedagogical illustration of the fundamental concepts of soft matter physics that aid in understanding biomechanical phenomena from the scale of tissues to proteins. Examples of up-to-date research are introduced to elaborate these concepts. Challenges in applying physics models to biology have also been discussed for biologists and physicists to meet in the field of mechanobiology.

Curvature-Induced Cell Rearrangements in Biological Tissues.

On a curved surface, epithelial cells can adapt to geometric constraints by tilting and by exchanging their neighbors from apical to basal sides, known as an apico-basal topological transition 1 (AB-T1). The relationship between cell tilt, AB-T1s, and tissue curvature still lacks a unified understanding. Here, we propose a general framework for cell packing in curved environments and explain the formation of AB-T1s from the perspective of strain anisotropy. We find that steep curvature gradients can lead to cell tilting and induce AB-T1s. Alternatively, pressure differences across the epithelial tissue can drive AB-T1s in regions of large curvature anisotropy. The two mechanisms compete to determine the impact of tissue geometry and mechanics on optimized cell rearrangements in three dimensions.

Inhomogeneous mechanotransduction defines the spatial pattern of apoptosis-induced compensatory proliferation.

The number of cells in tissues is controlled by cell division and cell death, and its misregulation could lead to pathological conditions such as cancer. To maintain the cell numbers, a cell-elimination process called apoptosis also stimulates the proliferation of neighboring cells. This mechanism, apoptosis-induced compensatory proliferation, was originally described more than 40 years ago. Although only a limited number of the neighboring cells need to divide to compensate for the apoptotic cell loss, the mechanisms that select cells to divide have remained elusive. Here, we found that spatial inhomogeneity in Yes-associated protein (YAP)-mediated mechanotransduction in neighboring tissues determines the inhomogeneity of compensatory proliferation in Madin-Darby canine kidney (MDCK) cells. Such inhomogeneity arises from the non-uniform distribution of nuclear size and the non-uniform pattern of mechanical force applied to neighboring cells. Our findings from a mechanical perspective provide additional insight into how tissues precisely maintain homeostasis.

Abnormal dynamics of brain functional networks in children with Tourette syndrome.

Tourette syndrome (TS) is a childhood-onset neurodevelopmental disorder characterized by the presence of multiple motor and vocal tics. Research using resting-state functional magnetic resonance imaging (rfMRI) have found aberrant static functional connectivity (FC) and its topological properties in the brain networks of TS. Our study is the first to investigate the dynamic functional connectivity (dFC) in the whole brain network of TS patients, focusing on the temporal properties of dFC states and the temporal variability of topological organization. The rfMRI data of 36 male children with TS and 27 matched healthy controls were collected and further analyzed by group spatial independent component analysis, sliding windows approach based dFC analysis, k-means clustering analysis, and graph theory analysis. The clustering analysis identified three dFC states. Of these states, state 2, characterized by increased inter-network connections in subcortical network (SCN), sensorimotor network (SMN), and default mode network (DMN), and decreased inter-network connections between salience network (SAN) and executive control network (ECN), was found to have higher fractional window and dwell time in TS, which was also positively correlated with tic severity. TS patients also exhibited higher temporal variability of whole-brain-network global efficiency and local efficiency, and higher temporal variability of nodal efficiency and local efficiency in SCN, DMN, ECN, SAN, and SMN. Additionally, temporal variability of the efficiency and local efficiency in insula was positively correlated with tic severity. Our findings revealed abnormal temporal property of dFC states and temporal variability of topological organization in TS, providing new insights into clinical diagnoses and neuropathology of TS.

Interfacial friction and substrate deformation mediate long-range signal propagation in tissues.

Tissue layers can generally slide at the interface, accompanied by the dissipation due to friction. Nevertheless, it remains elusive how force could propagate in a tissue with such interfacial friction. Here, we elaborate the force dynamics in a prototypical multilayer system in which an epithelial monolayer was cultivated upon an elastic substrate in contact with a hard surface, and discover a novel mechanism of pronounced force propagation over a long distance due to interfacial dynamics between substrate layers. We derived an analytical model for the dynamics of the elastic substrate under the shear stress provided by the cell layer at the surface boundary and the friction at bottom. The model reveals that sliding between substrate layers leads to an expanding stretch regime from a shear regime of substrate deformation in time and space. The regime boundary propagating diffusively with a speed depending on the stiffness, thickness, and slipperiness of the substrate, is a robust nature of a deformed elastic sheet with interfacial friction. These results shed new light on force propagation in tissues and our model could serve as a basis for studies of such propagation in a more complex tissue environment.

Multivariate Classification of Brain Blood-Oxygen Signal Complexity for the Diagnosis of Children with Tourette Syndrome.

Tourette syndrome (TS) is a childhood-onset neuropsychiatric disorder characterized by the presence of multiple motor and vocal tics. Because of its varied clinical expressions and lack of reliable diagnostic biomarker, present TS diagnosis still depends on qualitative descriptions of symptoms. Our study aimed to investigate whether the complexity of resting state brain activity can serve as a potential biomarker for TS diagnosis, since it has been used successfully in various neuropsychiatric disorders, including two common TS comorbidities: attention-deficit hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD). In the current study, we used both univariate analysis and multivariate searchlight analysis with both linear and non-linear classification methods to explore the group differences in the complexity of resting state brain blood oxygen level-dependent (BOLD) signals between 25 TS boys without comorbidity and 25 sex, age and educational years matched healthy controls (HCs). We also investigated the relation between symptom severity in TS patients (YGTSS scores) and complexity indices derived from different analysis methods. We found: i) univariate analysis revealed reduced complexity in TS patients in the left cerebellum, left superior frontal gyrus, and left medial frontal gyrus; ii) multivariate analysis with non-linear classification method achieved the highest performance (accuracy: 0.94, sensitivity: 0.96, specificity: 0.92, AUC: 0.95) in bilateral supplementary motor areas; iii) significant correlations were found between complexity index derived from multivariate analysis with non-linear classification method and Tic severity (YGTSS scores) in the left cerebellum (r = 0.523, with YGTSS phonic) and in the right supplementary motor area (r = 0.767, with YGTSS motor). Taken together, these results suggested that complexity of resting state BOLD activity is a highly effective index for differentiating TS patients from normal controls. It has a good potential to be a quantitative biomarker for TS diagnosis.

Giant axonal neuropathy (GAN) in an 8-year-old girl caused by a homozygous pathogenic splicing variant in GAN gene.

Giant axonal neuropathy (GAN) is a progressive disease that involves the peripheral and central nervous systems. This neurodegenerative disease is caused by variants in the GAN gene encoding gigaxonin, and is inherited in an autosomal recessive manner. Herein, we performed whole-exome sequencing on a 8-year-old child with dense, curly hair, weakness in both lower limbs, and abnormal MRI. The child was born to consanguineous parents. Our results revealed that the child carried the c.1373+1G>A homozygous pathogenic variant of the GAN gene, while both parents were heterozygous carriers. According to the validation at the cDNA levels, the splicing variant led to the skipping of exon 8 and affected the Kelch domain's formation. Unlike the previously reported cases of GAN, the child's clinical manifestations revealed peripheral nervous system involvement, no vertebral signs, cerebellar signs, and spasticity, but only MRI abnormalities. These results suggested that the patient's central nervous system was mildly involved, which may be related to the genotype. In order to further clarify the correlation between GAN genotype and phenotype, combined with this patient, 54 cases of reported homozygous variants of the GAN gene were merged for the analysis of genotype and phenotype. The results revealed a certain correlation between the GAN gene variant domain and the patient's clinical phenotype, such as central nervous system involvement and age of onset.

Tic Detection in Tourette Syndrome Patients Based on Unsupervised Visual Feature Learning.

A clinical diagnosis of tic disorder involves several complex processes, among which observation and evaluation of patient behavior usually require considerable time and effective cooperation between the doctor and the patient. The existing assessment scale has been simplified into qualitative and quantitative assessments of movements and sound twitches over a certain period, but it must still be completed manually. Therefore, we attempt to find an automatic method for detecting tic movement to assist in diagnosis and evaluation. Based on real clinical data, we propose a deep learning architecture that combines both unsupervised and supervised learning methods and learns features from videos for tic motion detection. The model is trained using leave-one-subject-out cross-validation for both binary and multiclass classification tasks. For these tasks, the model reaches average recognition precisions of 86.33% and 86.26% and recalls of 77.07% and 78.78%, respectively. The visualization of features learned from the unsupervised stage indicates the distinguishability of the two types of tics and the nontic. Further evaluation results suggest its potential clinical application for auxiliary diagnoses and evaluations of treatment effects.

Establishment of an induced pluripotent stem cell line (ZJSHi001-A) from a patient with epileptic encephalopathy carrying KCNB1 Glu330Asp mutation.

Early infantile epileptic encephalopathy 26 (EE26) is a form of epileptic encephalopathy, a heterogeneous group of severe childhood-onset epilepsies characterized by refractory seizures, neurodevelopmental impairment, and poor prognosis. A recent study has shown that the KCNB1 gene mutation is associated with EE26; yet, the exact mechanism remains unclear. In this study, we produced an induced pluripotent stem cell line (iPSC) with a heterozygous variant of the KCNB1 gene (c.990G > T, p.Glu330Asp). Induced iPSCs were generated from peripheral blood mononuclear cells (PBMCs) obtained from a female child aged 6 with KCNB1 gene c. 990G > T and p.Glu330Asp heterozygous mutation.

Physicochemical and textural characteristics and volatile compounds of semihard goat cheese as affected by starter cultures.

Today, cheese is valued because of its high nutritional value and unique characteristics. Improving the texture and flavor of cheese by selecting suitable starter cultures is an important way to promote the development of cheese industry. The effect of starter cultures on the physicochemical and textural properties and volatile compounds during the ripening of semihard goat cheese were investigated in this work. Different starter cultures-mesophilic (M) and thermophilic starters (T), Lactobacillus plantarum ssp. plantarum ATCC 14917 (Lp), a mix of the M and T starters (M1), and mix of the M, T, and Lp starters (M2)-were used in the production of the goat cheeses. Volatile compounds were determined by a solid-phase microextraction/gas chromatography-mass spectrometric (SPME/GC-MS) method. The results showed that the moisture content of cheeses produced with the 5 kinds of starter cultures decreased after maturation, whereas ash content increased. The pH values of goat cheeses decreased first and then increased during maturity, and the pH value of M2 cheese was the lowest among the cheeses. The hardness and chewiness of the cheeses increased with increasing maturity, whereas cohesiveness, springiness, and resilience showed the opposite tendency. The 60-d-old cheese made with Lp had the highest chewiness, cohesiveness, springiness, and resilience, whereas the 60-d-old cheese made with M2 had the highest hardness. A total of 53 volatile components were identified by SPME/GC-MS, and carboxylic acids, alcohols, ketones, and esters were the 4 major contributors to the characteristic flavors of the cheeses. Volatile components and their contents differed greatly among the produced cheeses. The M2 cheese contained the highest relative content of the main volatile compounds (90.10%), especially butanoic acid and acetoin. Through a comprehensive comparison of the results, we concluded that M2 cheese had a dense texture and milky flavor, and M2 is a potential starter culture candidate for the production of goat cheese.

Electrophysiological features: The next precise step for SCN2A developmental epileptic encephalopathy.

BACKGROUND: To investigate the relationships among phenotypes, genotypes, and funotypes of SCN2A-related developmental epileptic encephalopathy (DEE). METHODS: We enrolled five DEE patients with five de novo variants of the SCN2A. Functional analysis and pharmacological features of Nav1.2 channel protein expressed in HEK293T cells were characterized by whole-cell patch-clamp recording. RESULTS: The phenotypes of c.4712T>C(p. I1571T), c.2995G>A(p.E999K), and c.4015A>G(p. N1339D) variants showed similar characteristics, including early seizure onset with severe to profound intellectual disability. Electrophysiological recordings revealed a hyperpolarizing shift in the voltage dependence of the activation curve and smaller recovery time constants of fast-inactivation than in wild type, indicating a prominent gain of function (GOF). Moreover, pharmacological electrophysiology showed that phenytoin inhibited over a 70% peak current and was more effective than oxcarbazepine and carbamazepine. In contrast, c.4972C>T (p.P1658S) and c.5317G>A (p.A1773T) led to loss of function (LOF) changes, showing reduced current density and enhanced fast inactivation. Both showed seizure onset after 3 months of age with moderate development delay. Interestingly, we discovered that choreoathetosis was a specific phenotype feature. CONCLUSION: These findings provided the insights into the phenotype-genotype-funotype relationships of SCN2A-related DEE. The preliminary evaluation using the distinct hints of GOF and LOF helped plan the treatment, and the next precise step should be electrophysiological study.

Altered Cerebello-Motor Network in Familial Cortical Myoclonic Tremor With Epilepsy Type 1.

BACKGROUND: Intronic pentanucleotide insertion in the sterile alpha motif domain-containing 12 gene was recently identified as the genetic cause of familial cortical myoclonic tremor with epilepsy type 1. OBJECTIVES: We thereafter conducted a multimodal MRI research to further understand familial cortical myoclonic tremor with epilepsy type 1. METHODS: We enrolled 31 patients carrying heterozygous pathogenic intronic pentanucleotide insertion in the sterile alpha motif domain-containing 12 gene and 31 age- and sex-matched healthy controls. We compared multimodal MRI metrics, including voxel-based morphometry, fractional anisotropy of diffuse tensor imaging, frequency-dependent percent amplitude fluctuation, and seed-based functional connectivity of resting-state functional MRI. RESULTS: Significant decreased gray matter volume was found in the cerebellum. Percent amplitude fluctuation analysis showed significant interaction effect of "Frequency by Group" in three regions, including the vermis VIII, left cerebellar lobule VIII, and left precentral gyrus. Specifically, the lowest-frequency band exhibited significant increased percent amplitude fluctuation in patients in the two cerebellar subregions, whereas the highest-frequency band exhibited decreased percent amplitude fluctuation in the precentral gyrus in patients. Discriminative analysis by support vector machine showed a mean accuracy of 82% (P = 1.0-5 ). An increased functional connectivity between vermis VIII and the left precentral gyrus was found in patients with familial cortical myoclonic tremor with epilepsy type 1. A positive correlation between the percent amplitude fluctuation in the left cerebellar lobule VIII and duration of cortical tremor was also found. CONCLUSION: The cerebellum showed both structural and functional damages. The distinct change of spontaneous brain activity, that is, increased ultra-low-frequency amplitude in the cerebellum and the decreased higher-frequency amplitude in the motor cortex, might be a pathophysiological feature of familial cortical myoclonic tremor with epilepsy type 1. © 2020 International Parkinson and Movement Disorder Society.

Autosomal dominant hereditary spastic paraplegia caused by mutation of UBAP1.

Hereditary spastic paraplegias (HSP) are a group of rare neurodegenerative diseases characterized by progressive spastic paraparesis. UBAP1 was recently found to induce a rare type of HSP (SPG80). We identified a family with eight inherited spastic paraplegic patients carrying a novel heterozygous mutation c.279delG (p.S94Vfs*9) of UBAP1. We demonstrated a lack of functional UBAP1 in these patients, resulting in the neurological disorder caused by interceptions of the ESCRT pathway. Extending from the older onset-age identified from this family, we found that comparing with the European and other populations, Asian patients displayed less proportion of severe patients and an older average age at onset. The origins of SPG80 patients associated with both their onset age and their disease severity, while the age at onset was not correlated with the disease severity.

Frequency-Specific Regional Homogeneity Alterations in Tourette Syndrome.

Tourette syndrome (TS) is a developmental neuropsychiatric disorder with onset during childhood. Because of its complex spectrum of phenotypes, the underlying pathophysiology of TS is still unclear. Resting-state functional magnetic resonance imaging demonstrated aberrant spontaneous neural synchronization in conventional frequency band (0.01-0.08 Hz) in TS. No published studies have reported abnormalities of local synchronization across different frequency bands. We estimated the alterations of local synchronization across five bands ranging from 0 to 0.25 Hz. Seventy-nine children with TS and 63 age-, sex-, and handedness-matched healthy children were recruited. Frequency-specific regional homogeneity (ReHo) and independent component analysis were used to identify functional alterations between TS and healthy children. TS patients showed significantly increased ReHo in the left precentral gyrus and decreased ReHo in the right operculum. Abnormal ReHo alterations of the superior frontal gyrus, superior parietal gyrus, anterior cingulate gyrus, putamen, superior temporal gyrus, and operculum were observed in different frequency bands. TS patients showed increased connectivity of the right superior frontal gyrus within the left executive control network. In addition, a significantly negative correlation was found between Yale Global Tic Severity Scale (YGTSS) vocal score and ReHo values of the right operculum in the highest frequency bands (0.198-0.25 Hz), while a significant positive correlation was found between YGTSS motor score and altered connectivity of the right superior frontal gyrus. The present study revealed frequency-specific abnormal alterations of ReHo in the whole brain and altered connectivity within the executive control network of TS children. Its neural importance and clinical practicability require further investigation.