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1.
J Hum Genet ; 69(2): 85-90, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38030753

RESUMO

Ubiquitin-specific protease 8 (USP8) is a deubiquitinating enzyme involved in deubiquitinating the enhanced epidermal growth factor receptor for escape from degradation. Somatic variants at a hotspot in USP8 are a cause of Cushing's disease, and a de novo germline USP8 variant at this hotspot has been described only once previously, in a girl with Cushing's disease and developmental delay. In this study, we investigated an exome-negative patient with severe developmental delay, dysmorphic features, and multiorgan dysfunction by long-read sequencing, and identified a 22-kb de novo germline deletion within USP8 (chr15:50469966-50491995 [GRCh38]). The deletion involved the variant hotspot, one rhodanese domain, and two SH3 binding motifs, and was presumed to be generated through nonallelic homologous recombination through Alu elements. Thus, the patient may have perturbation of the endosomal sorting system and mitochondrial autophagy through the USP8 defect. This is the second reported case of a germline variant in USP8.


Assuntos
Hipersecreção Hipofisária de ACTH , Feminino , Humanos , Endopeptidases/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Células Germinativas/metabolismo , Mutação em Linhagem Germinativa/genética , Hipersecreção Hipofisária de ACTH/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo
2.
J Med Genet ; 58(8): 505-513, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32732225

RESUMO

BACKGROUND: Variants in the type IV collagen gene (COL4A1/2) cause early-onset cerebrovascular diseases. Most individuals are diagnosed postnatally, and the prenatal features of individuals with COL4A1/2 variants remain unclear. METHODS: We examined COL4A1/2 in 218 individuals with suspected COL4A1/2-related brain defects. Among those arising from COL4A1/2 variants, we focused on individuals showing prenatal abnormal ultrasound findings and validated their prenatal and postnatal clinical features in detail. RESULTS: Pathogenic COL4A1/2 variants were detected in 56 individuals (n=56/218, 25.7%) showing porencephaly (n=29), schizencephaly (n=12) and others (n=15). Thirty-four variants occurred de novo (n=34/56, 60.7%). Foetal information was available in 47 of 56 individuals, 32 of whom (n=32/47, 68.1%) had one or more foetal abnormalities. The median gestational age at the detection of initial prenatal abnormal features was 31 weeks of gestation. Only 14 individuals had specific prenatal findings that were strongly suggestive of features associated with COL4A1/2 variants. Foetal ventriculomegaly was the most common initial feature (n=20/32, 62.5%). Posterior fossa abnormalities, including Dandy-Walker malformation, were observed prenatally in four individuals. Regarding extrabrain features, foetal growth restriction was present in 16 individuals, including eight individuals with comorbid ventriculomegaly. CONCLUSIONS: Prenatal observation of ventriculomegaly with comorbid foetal growth restriction should prompt a thorough ultrasound examination and COL4A1/2 gene testing should be considered when pathogenic variants are strongly suspected.


Assuntos
Colágeno Tipo IV/genética , Mutação/genética , Síndrome de Dandy-Walker/genética , Feminino , Humanos , Masculino , Gravidez , Ultrassonografia Pré-Natal/métodos
3.
Sensors (Basel) ; 22(12)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35746105

RESUMO

We developed a path-planning system for radiation source identification devices using 4π gamma imaging. The estimated source location and activity were calculated by an integrated simulation model by using 4π gamma images at multiple measurement positions. Using these calculated values, a prediction model to estimate the probability of identification at the next measurement position was created by via random forest analysis. The path-planning system based on the prediction model was verified by integrated simulation and experiment for a 137Cs point source. The results showed that 137Cs point sources were identified using the few measurement positions suggested by the path-planning system.


Assuntos
Diagnóstico por Imagem , Planejamento da Radioterapia Assistida por Computador , Radioisótopos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
4.
AJP Rep ; 14(1): e1-e6, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38269130

RESUMO

Vitamin K deficiency bleeding (VKDB) in neonates is a significant disorder that causes skin, gastrointestinal, and intracranial hemorrhaging. Early-onset VKDB occurs within 24 hours of birth, and its prognosis is poor due to severe hemorrhage. The causes of early-onset VKDB include maternal intake of warfarin and anticoagulants, and maternal vitamin K deficiency. We report the case of a neonate with early-onset VKDB born to a mother with Crohn's disease. The neonate developed severe cerebellar hemorrhage on the day of birth and subsequent noncommunicating hydrocephalus requiring a ventriculoperitoneal shunt. The mother had a 14-year history of Crohn's disease and short bowel owing to intestinal resection. She was in complete remission during pregnancy according to the Crohn's Disease Activity Index. Endoscopic examination performed shortly before pregnancy revealed inflammatory findings in the residual small intestine. Her blood tests at delivery showed an elevated prothrombin induced by vitamin K deficiency or antagonist II (PIVKA-II) level of 26,900 mAU/mL. A definitive protocol to prevent early-onset VKDB in mothers with Crohn's disease complicated by a short bowel is lacking. Administering vitamin K to mothers with elevated PIVKA-II levels before delivery may help prevent early-onset VKDB.

5.
Pediatr Int ; 54(6): 923-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23279022

RESUMO

The case is described herein of a patient with alveolar capillary dysplasia with double-outlet right ventricle and duodenal atresia who survived for a remarkably long time. The newborn girl was born at a gestational age of 36 weeks and weighed 1926 g. One min after delivery the Apgar score was 4. The patient had persistent pulmonary hypertension (PH) and needed nitric oxide inhalation and i.v. epoprostenol all through her life. Although other oral medications for PH were tried, they could not be used in practice because of gastrointestinal complications. The patient died on the 237 th day of life as a result of worsening PH associated with infection.


Assuntos
Epoprostenol/análogos & derivados , Epoprostenol/uso terapêutico , Óxido Nítrico/administração & dosagem , Síndrome da Persistência do Padrão de Circulação Fetal/tratamento farmacológico , Piperazinas/uso terapêutico , Alvéolos Pulmonares/anormalidades , Sulfonamidas/uso terapêutico , Sulfonas/uso terapêutico , Administração por Inalação , Bosentana , Broncodilatadores/administração & dosagem , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Epoprostenol/administração & dosagem , Evolução Fatal , Feminino , Seguimentos , Humanos , Recém-Nascido , Síndrome da Persistência do Padrão de Circulação Fetal/diagnóstico , Síndrome da Persistência do Padrão de Circulação Fetal/fisiopatologia , Piperazinas/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/uso terapêutico , Alvéolos Pulmonares/fisiopatologia , Purinas/administração & dosagem , Purinas/uso terapêutico , Citrato de Sildenafila , Sulfonamidas/administração & dosagem , Sulfonas/administração & dosagem , Fatores de Tempo , Vasodilatadores/administração & dosagem , Vasodilatadores/uso terapêutico
6.
J Obstet Gynaecol Res ; 37(10): 1313-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21535310

RESUMO

AIM: The aim of this study is to elucidate whether the stage of chorioamnionitis is or is not associated with the development of neonatal diseases. MATERIAL & METHODS: We reviewed the neonatal intensive care unit discharge files and placental pathology reports of 302 preterm infants. The presence of various stages of chorioamnionitis as well as absence of an association with chorioamnionitis (non-chorioamnionitis) were compared among neonatal diseases. RESULTS: Preterm infants were grouped according to three stages of chorioamnionitis or the absence of an association with chorioamnionitis. Gestational age differed significantly between these groups. Before controlling for gestational age, the chorioamnionitis stage was significantly higher among infants with chronic lung disease, retinopathy of prematurity and intraventricular hemorrhage than in infants without these diseases. On the other hand, the chorioamnionitis stage was lower in infants with respiratory distress syndrome than without. After controlling for gestational age, the stage of chorioamnionitis was significantly lower in infants with respiratory distress syndrome than in infants without respiratory distress syndrome, whereas, significant differences were not detected between the presence and absence of chronic lung disease, retinopathy of prematurity and intraventricular hemorrhage. Furthermore, gestational age was a significant risk factor for chronic lung disease, respiratory distress syndrome, retinopathy of prematurity and intraventricular hemorrhage. CONCLUSIONS: We found no significant differences in stages of chorioamnionitis between infants with and without neonatal diseases except for respiratory distress syndrome. A significant inverse relationship was observed between the stage of chorioamnionitis and development of respiratory distress syndrome.


Assuntos
Corioamnionite/patologia , Doenças do Prematuro/diagnóstico , Placenta/patologia , Adulto , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Masculino , Gravidez , Índice de Gravidade de Doença
7.
J Neurophysiol ; 104(6): 3625-43, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20943943

RESUMO

We used mutual information analysis of neuronal activity in the macaque anterior intraparietal area (AIP) to examine information processing during a hand manipulation task. The task was to reach-to-grasp a three-dimensional (3D) object after presentation of a go signal. Mutual information was calculated between the spike counts of individual neurons in 50-ms-wide time bins and six unique shape classifications or 15 one-versus-one classifications of these shapes. The spatiotemporal distribution of mutual information was visualized as a two-dimensional image ("information map") to better observe global profiles of information representation. In addition, a nonnegative matrix factorization technique was applied for extracting its structure. Our major finding was that the time course of mutual information differed significantly according to different classes of task-related neurons. This strongly suggests that different classes of neurons were engaged in different information processing stages in executing the hand manipulation task. On the other hand, our analysis revealed the heterogeneous nature of information representation of AIP neurons. For example, "information latency" (or information onset) varied among individual neurons even in the same neuron class and the same shape classification. Further, some neurons changed "information preference" (i.e., shape classification with the largest amount of information) across different task periods. These suggest that neurons encode different information in the different task periods. Taking the present result together with previous findings, we used a Gantt chart to propose a hypothetical scheme of the dynamic interactions between different types of AIP neurons.


Assuntos
Força da Mão/fisiologia , Mãos/fisiologia , Neurônios/fisiologia , Lobo Parietal/fisiologia , Desempenho Psicomotor/fisiologia , Potenciais de Ação/fisiologia , Animais , Mapeamento Encefálico , Forma Celular , Apresentação de Dados , Teoria da Informação , Macaca , Matemática , Neurônios/classificação , Neurônios/ultraestrutura , Lobo Parietal/citologia , Fatores de Tempo
8.
Opt Express ; 18(7): 7203-9, 2010 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-20389741

RESUMO

We present and demonstrate the use of an extreme ultraviolet (EUV) microscope that was developed in-house. Images are acquired using Bragg reflection multilayer optics and a laser-produced plasma light source. The upper-limit spatial resolution of the EUV microscope is 130 nm with a 10 ns exposure time and 250 x 250 microm(2) field of view. Resolution is superior to that of visible microscopes with the same size of field of view, and the exposure time is short enough to observe fine structures in-vivo. Observation of the cerebral cortex of a mouse is demonstrated.


Assuntos
Microanálise por Sonda Eletrônica/métodos , Microscopia/métodos , Animais , Córtex Cerebral/patologia , Desenho de Equipamento , Processamento de Imagem Assistida por Computador , Camundongos , Microscopia Eletrônica de Transmissão/métodos , Óptica e Fotônica , Polímeros/química , Temperatura , Raios Ultravioleta
9.
Biomed Eng Lett ; 9(2): 181-187, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31168423

RESUMO

Gaze or eye movements are used as a communication interface in daily life. Herein, we developed a simple method for gaze estimations based on planar approximations of voltage ratios calculated from multiple electro-oculogram signals not affected by drift phenomena, which decrease accuracy. Subsequently, we conducted simulations using an eyeball battery model and investigated the effects of adjusting electrode arrangements, determination coefficients for planar approximations of voltage ratios, and threshold values for angles between simultaneous linear equations, to improve the estimation accuracy and decreased the number of required electrodes. Numerical experiments were used to identify arrangements of six electrodes with errors that were approximately 5° less than those of nine-electrode L-shaped arrangements, indicating improved estimation accuracy with fewer electrodes.

10.
Neural Netw ; 21(7): 936-44, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18280701

RESUMO

We propose a computational model of perceptual grouping for explaining the 3D shape representation of an illusory percept called "mime effect." This effect is associated with the generation of an illusory, volumetric perception that can be induced by particular distributions of inducing stimuli such as cones, whose orientations affect the stability of illusory perception. The authors have attempted to explain the characteristics of the shape representation of the mime effect using a neural network model that consists of four types of cells-encoding (E), normalizing (N), energetic (EN), and geometric (G) cells. E cells represent both the positions and orientations of inducing stimuli and the mime-effect shape, and N cells regulate the activity of E cells. The interactions of E cells generate dynamics whose mode indicates the stability of illusory perception; a stable dynamics mode indicates a stable perception, whereas a chaotic dynamics mode indicates an unstable perception. EN cells compute the Liapunov energetic exponent (LEE) from an energy function of the system of E cells. The stable and chaotic dynamics modes are identified by strictly negative and strictly positive values of LEE, respectively. In case of stability, G cells perform a particular surface interpolation for completing the mime effect shape. The authors confirm the model behaviour by means of computer-simulated experiments. The relation between the model behaviour and the shape representation in the human brain is also discussed.


Assuntos
Simulação por Computador , Ilusões/fisiologia , Redes Neurais de Computação , Percepção/fisiologia , Percepção Visual , Algoritmos , Humanos , Modelos Neurológicos , Dinâmica não Linear , Orientação , Reconhecimento Visual de Modelos
11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(1 Pt 1): 012901, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17358209

RESUMO

We derived semianalytically the transient solution of a delayed differential equation that had been shown to be a simple but good model of the sensory-motor system. In the present Brief Report, we applied this transient solution for studying the global nature of the transient tracking motion when visual target information is changed suddenly. The results clarified that the dynamic error minimization principle in hand motion observed experimentally is robust over a wide range of the parameter space of the delay time, the time constant, and the feedforward parameter.


Assuntos
Biofísica/métodos , Modelos Neurológicos , Sistema Nervoso , Desempenho Psicomotor , Visão Ocular , Percepção Visual , Humanos , Modelos Estatísticos , Movimento (Física) , Movimento , Tempo de Reação , Fatores de Tempo
13.
Biol Cybern ; 92(4): 219-28, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15765212

RESUMO

It has been proposed that the central nervous system determines reaching movement trajectories so as to minimize the positional variance of the endpoint in the presence of signal-dependent noise. The hypothesis well reproduces the empirical movement trajectories for noise to the control signal whose variance is proportional to the second power of the amplitude of the control signal. However, empirical studies do not necessarily exhibit such a simple signal-noise relationship. The studies exhibit a wide distribution of estimates of the value of the exponent. This discrepancy raises the question of how the minimum endpoint variance trajectory depends on the value of the exponent. To address this question, we calculated minimum endpoint variance trajectories in simulations in which the value of the exponent was varied from 0 to 3. We found that the optimal trajectories differed according to the value of the exponent, and the profiles of optimal trajectories gradually diverged from the empirical ones as the value approached 0, though this change was not remarkable for larger values. Moreover, the optimal trajectories failed to replicate Fitts' law when the value was not equal to 2. These results suggest that the acceptability of the minimum endpoint variance theory depends on the value of the exponent in our motor system.


Assuntos
Braço/fisiologia , Modelos Neurológicos , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Fenômenos Biomecânicos , Humanos , Contração Muscular/fisiologia , Redes Neurais de Computação , Dinâmica não Linear , Movimentos Sacádicos/fisiologia
14.
Phys Rev Lett ; 93(16): 168105, 2004 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-15525039

RESUMO

We investigated particularly the proactive nature of the visual-motor system by steady and transient experiments of a hand-tracking task, and confirmed that the hand motion precedes on the average the target motion in steady runs within a finite frequency range of the sinusoidal target motion. The question why and how much the hand motion should precede was answered by frequency-jump experiments. The results implied that the positive phase shift of the hand motion represents the proactive nature of the visual-motor control system which is adaptationally developed for each person to minimize the transient error of the hand motion when the target motion changes unexpectedly.


Assuntos
Mãos/fisiologia , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Evolução Biológica , Humanos , Masculino
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