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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).
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Pueblos del Este de Asia , Epilepsia , Humanos , Femenino , Fenotipo , Epilepsia/genética , Convulsiones/genéticaRESUMEN
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.
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Física , Biofisica , Fenómenos BiomecánicosRESUMEN
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.
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Células Epiteliales , EpitelioRESUMEN
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.
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Neuropatía Axonal Gigante , Enfermedades Neurodegenerativas , Consanguinidad , Proteínas del Citoesqueleto/genética , Neuropatía Axonal Gigante/genética , Neuropatía Axonal Gigante/patología , Homocigoto , HumanosRESUMEN
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.
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Queso/análisis , Queso/microbiología , Manipulación de Alimentos/métodos , Cabras , Compuestos Orgánicos Volátiles/análisis , Animales , Fenómenos Químicos , Fermentación , Lactobacillus delbrueckii/metabolismo , Lactobacillus plantarum/metabolismo , Lactococcus/metabolismo , Lactococcus lactis/metabolismo , Sensación , Microextracción en Fase Sólida/veterinaria , Streptococcus thermophilus/metabolismo , GustoRESUMEN
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.
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Proteínas Portadoras/genética , Genes Dominantes , Mutación , Paraplejía Espástica Hereditaria/genética , Adolescente , Edad de Inicio , Salud de la Familia , Mutación del Sistema de Lectura , Variación Genética , Heterocigoto , Humanos , Masculino , Linaje , Análisis de Secuencia de ADNRESUMEN
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.
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Epilepsias Mioclónicas , Epilepsia , Cerebelo , Epilepsias Mioclónicas/diagnóstico por imagen , Epilepsias Mioclónicas/genética , Humanos , Imagen por Resonancia Magnética , Temblor/diagnóstico por imagen , Temblor/genéticaRESUMEN
Dysphagia is a common non-primary symptom of patients with Parkinson's disease. The aim of this study is to investigate the underlying alterations of brain functional connectivity in Parkinson's disease patients with dysphagia by resting-state functional magnetic resonance imaging. We recruited 13 Parkinson's disease patients with dysphagia and ten patients without dysphagia, diagnosed by videofluoroscopic study of swallowing. Another 13 age and sex-matched healthy subjects were recruited. Eigenvector centrality mapping was computed to identify functional connectivity alterations among these groups. Parkinson's disease patients with dysphagia had significantly increased functional connectivity in the cerebellum, left premotor cortex, the supplementary motor area, the primary motor cortex, right temporal pole of superior temporal gyrus, inferior frontal gyrus, anterior cingulate cortex and insula, compared with patients without dysphagia. This study suggests that functional connectivity changes in swallowing-related cortexes might contribute to the occurrence of dysphagia in Parkinson's disease patients.
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Encéfalo/fisiopatología , Trastornos de Deglución/etiología , Red Nerviosa/fisiopatología , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/etiología , Encéfalo/diagnóstico por imagen , Estudios de Casos y Controles , Trastornos de Deglución/diagnóstico por imagen , Trastornos de Deglución/fisiopatología , Femenino , Neuroimagen Funcional , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/fisiopatologíaRESUMEN
PURPOSE: To investigate the differences in spontaneous brain activity between Parkinson's disease (PD) patients with rapid eye movement sleep behavior disorder (RBD), PD patients without RBD, and normal controls, which may shed new light on the neural mechanism of RBD. MATERIALS AND METHODS: Eighteen PD patients with RBD, 16 patients without RBD, and 19 age- and gender-matched normal controls underwent clinical assessment and functional magnetic resonance imaging (fMRI) with a 3.0T scanner. Resting-state fMRI scans were collected using an echo planar imaging sequence. Amplitude of low-frequency fluctuations (ALFF) were calculated to measure spontaneous brain activity in each subject. RESULTS: Compared with PD patients without RBD, patients with RBD exhibited significantly decreased ALFF values (P < 0.001, cluster level) in primary motor cortex extending to premotor cortex. Compared with normal controls, PD patients exhibited decreased ALFF values (P < 0.001, cluster level) in caudate and putamen (P < 0.001, cluster level), and increased ALFF values (P = 0.03, cluster level) in prefrontal cortex. CONCLUSION: The altered spontaneous brain activity in motor cortex may contribute to the pathogenesis of RBD in PD patients, which further supports the idea that the pathophysiology of RBD involves not only midbrain dysfunction but also cerebral cortex abnormalities. Our findings provide additional insight into the neural mechanism of RBD and may drive future research to develop better treatment. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 3 J. MAGN. RESON. IMAGING 2017;46:697-703.
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Encéfalo/fisiopatología , Imagen por Resonancia Magnética/métodos , Enfermedad de Parkinson/fisiopatología , Trastorno de la Conducta del Sueño REM/fisiopatología , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones , Trastorno de la Conducta del Sueño REM/complicaciones , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND: Postural deformities in the coronal plane were frequent and disabling complications of PD, which reduces the quality of life of patients. This study aimed to garner greater attention to the Parkinson disease (PD)-related postural trunk deviations in the coronal plane by exploring a method for diagnosis because of the lack of any uniform diagnostic criteria and epidemiological studies. It also aimed to provide correlation data in the Chinese PD patients. METHODS: In this cross-sectional study, 503 consecutive outpatients with PD were enrolled who underwent standardized clinical evaluation. The study recruited 83 PD patients diagnosed with Pisa syndrome (PS). Scoliosis and coronal imbalance were diagnosed accurately by radiographic data. The PD patients were compared based on the Cobb angle and coronal balance for several demographic and clinical variables. RESULTS: PD patients with PS had a prevalence of 16.5%. The prevalence of coronal imbalance and scoliosis was 10.34 and 7.75%, respectively. PD patients with PS were older and had a more severe disease, significantly longer disease duration and treatment duration, and reduced quality of life. The most important finding was that the different morphology of the spinal level had an effect on the severity of coronal balance or Cobb angle. CONCLUSIONS: The present study indicated that the postural deformities in the coronal plane were related to the morphology of the spinal level, especially the position of the Cobb angle. To benefit the PD patients with PS, the full-length standing spine radiographs should be performed as early as possible.
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Enfermedad de Parkinson/complicaciones , Escoliosis/diagnóstico , Escoliosis/etiología , Anciano , China , Estudios Transversales , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Radiografía , Factores de Riesgo , Escoliosis/epidemiologíaRESUMEN
OBJECTIVE: Familial cortical myoclonic tremor with epilepsy is a rare epilepsy syndrome. Herein, we report on nine Chinese familial cortical myoclonic tremor with epilepsy pedigrees to delineate its clinical and neurophysiological features. METHODS: Detailed clinical and neurophysiological data were obtained. Somatosensory evoked potential amplitudes and clinical profile were analyzed using multilevel statistical models. Age-at-onset anticipation was analyzed using Kaplan-Meier survival analysis. RESULTS: Fifty-five patients were interviewed directly, whose mean age at onset of cortical tremor and generalized tonic-clonic seizures were 31.0 ± 8.3 and 36.0 ± 7.9 years. Giant somatosensory evoked potential was detected in 87.5% (28 of 32) of patients, and long-latency cortical reflex was detected in 93.5% (29 of 31). Cortical tremor severity was significantly higher in patients with longer disease duration of cortical tremor (P = 0.0061). Somatosensory evoked potential amplitudes were significant higher in patients with higher level of cortical tremor severity (P = 0.0003) and those using antiepileptic drugs (P = 0.0150). Age-at-onset anticipation of cortical tremor with paternal transmission was found with statistical significance (P = 0.022). CONCLUSION: We provided the clinical and neurophysiological features of familial cortical myoclonic tremor with epilepsy patients. This study is reported for the presentation of this rare disease in a Chinese population with the largest single report on familial cortical myoclonic tremor with epilepsy worldwide. Age-at-onset anticipation of cortical tremor with paternal transmission was statistically significant, which further confirmed a possibility of unstable expanding repeat in the genetic mechanism of familial cortical myoclonic tremor with epilepsy. © 2016 International Parkinson and Movement Disorder Society.
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Anticipación Genética , Corteza Cerebral/fisiopatología , Epilepsias Mioclónicas/fisiopatología , Potenciales Evocados Somatosensoriales/fisiología , Adolescente , Adulto , Edad de Inicio , Anciano , China , Epilepsias Mioclónicas/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linaje , Adulto JovenRESUMEN
The purpose of the study is to investigate the multicellular homeostasis in epithelial tissues over very large timescales. Inspired by the receptor dynamics of IBCell model proposed by Rejniak et al. an on-grid agent-based model for multicellular system is constructed. Instead of observing the multicellular architectural morphologies, the diversity of homeostatic states is quantitatively analyzed through a substantial number of simulations by measuring three new order parameters, the phenotypic population structure, the average proliferation age and the relaxation time to stable homeostasis. Nearby the interfaces of distinct homeostatic phases in 3D phase diagrams of the three order parameters, intermediate quasi-stable phases of slow dynamics that features quasi-stability with a large spectrum of relaxation timescales are found. A further exploration on the static and dynamic correlations among the three order parameters reveals that the quasi-stable phases evolve towards two terminations, tumorigenesis and degeneration, which are respectively accompanied by rejuvenation and aging. With the exclusion of the environmental impact and the mutational strategies, the results imply that cancer and aging may share the non-mutational origin in the intrinsic slow dynamics of the multicellular systems.
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Envejecimiento/genética , Simulación por Computador , Homeostasis , Modelos Biológicos , Mutación/genética , Neoplasias/genética , Receptores de Superficie Celular/metabolismo , Animales , Proliferación Celular , Humanos , Fenotipo , Reproducibilidad de los Resultados , Factores de TiempoRESUMEN
BACKGROUND: Depression is a relatively common and serious nonmotor symptom of Parkinson's disease (PD), which reduces the quality of patients' life. Although disturbances in some related brain networks have been reported, the pathophysiology of depression in PD is still unclear. Here, we aim to investigate whole-brain functional connectivity patterns in depressed PD patients. METHODS: We recruited 17 PD patients diagnosed with major depressive disorder, 17 PD patients without depression, and 17 healthy control subjects. Resting-state functional MRI and eigenvector centrality mapping were used to identify functional connectivity alterations among these groups. RESULTS: Results showed that depressed PD patients had decreased functional connectivity in the left dorsolateral prefrontal cortex and right superior temporal gyrus and increased functional connectivity in the right posterior cingulate cortex, compared to nondepressed patients. In addition, there was a significant negative correlation between functional connectivity and depression scores in the posterior cingulate cortex. CONCLUSIONS: This study suggests that functional connectivity changes in certain nodes of brain networks might contribute to depression in patients with PD.
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Encéfalo/fisiopatología , Trastorno Depresivo Mayor/etiología , Trastorno Depresivo Mayor/patología , Vías Nerviosas/fisiología , Enfermedad de Parkinson/complicaciones , Anciano , Análisis de Varianza , Encéfalo/irrigación sanguínea , Estudios de Casos y Controles , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Examen Neurológico , Oxígeno/sangre , Escalas de Valoración PsiquiátricaRESUMEN
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.
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Discapacidad Intelectual , Discapacidad Intelectual Ligada al Cromosoma X , Trastornos del Neurodesarrollo , Masculino , Niño , Humanos , Discapacidades del Desarrollo/genética , Discapacidad Intelectual Ligada al Cromosoma X/genética , Discapacidad Intelectual/genética , Discapacidad Intelectual/diagnóstico , Empalme del ARN , Proteínas Adaptadoras Transductoras de Señales/genéticaRESUMEN
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.
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Tics , Síndrome de Tourette , Humanos , Masculino , Niño , Imagen por Resonancia Magnética/métodos , Encéfalo , Mapeo Encefálico/métodosRESUMEN
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.
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Encefalopatías , Células Madre Pluripotentes Inducidas , Masculino , Humanos , Preescolar , Células Madre Pluripotentes Inducidas/metabolismo , Leucocitos Mononucleares/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Mutación/genética , Encefalopatías/genéticaRESUMEN
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.
RESUMEN
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.
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Apoptosis , Mecanotransducción Celular , Animales , Perros , Apoptosis/fisiología , Muerte Celular , División Celular , Células de Riñón Canino Madin Darby , Proliferación Celular/fisiologíaRESUMEN
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.
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Trastorno por Déficit de Atención con Hiperactividad , Corteza Motora , Trastorno Obsesivo Compulsivo , Tics , Síndrome de Tourette , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Niño , Comorbilidad , Humanos , Masculino , Oxígeno , Tics/epidemiología , Síndrome de Tourette/diagnósticoRESUMEN
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.