Objective To observe the clinical phenotype of patients with CACNA1F gene variant. MethodsA retrospective clinical study. From January 1, 2022 to October 1, 2023, 36 patients with CACNA1F gene mutation-related eye diseases diagnosed by clinical examination and genetic testing in Changsha Aier Eye Hospital and Jinan Purui Eye Hospital were included in the study. All patients underwent best-corrected visual acuity (BCVA), medical optometry, fundus color photography, optical coherence tomography, full-field electroretinography (ERG), nystagmus examination, and genetic whole-exon sequencing. BCVA was performed using log visual acuity charts and converted to (logMAR). The nystagmus examination was performed using a helmet-mounted multifunctional video eye movement recording system. The clinical phenotypic characteristics were observed. Results At total of 36 patients were male, aged was (6.69±5.26) years. There were 36 cases of myopia (38.89%, 14/36), and the spherical equivalent was (−3.01±4.84) D. There were 14 different genetic variants including 7 cases of pathogenic variants, 20 cases of suspected pathogenic variants and 9 cases of unknown pathogenic variants, respectively. logMAR BCVA was 0.67±0.27; 26 patients had optic nerve atrophy (72.22%, 26/36); 6 had optical nerve hypoplasia (16.67%, 6/36). Fundus pigment dysplasia with mild iris transillumination was found in 4 cases (11.11%, 4/36). There were 5 cases of foveal dysplasia (Thomas grade) 1 (13.89%, 5/36). In full-field ERG examination, the B-wave reduction of the maximum mixed reaction of dark adaptation showed a negative waveform, and the amplitude of the shock potential was seriously reduced. The main phenotypes were residual type (residual dark adaptation 0.01 reaction wave and bright adaptation 3.0 reaction wave, and the response decreased at 30 Hz to a double-peak wide wave), dominant type of bright adaptation decreased (all light adaptation extinguished, all dark adaptation extinguished), and total extinction type (all light adaptation extinguished). Among them, 10 cases presented with residual ERG (27.78%, 10/36), 8 cases with photopic reduced ERG (22.22%, 8/36) and 18 with extinguished ERG (50.00%, 18/36). Low amplitude and high frequency pendulum (PLAHF) nystagmus waverforms were found in 32 cases (88.89%, 32/36), head oscillation in 27 cases (75.00%, 27/36) and chin up abnormal head posture in 26 cases (72.22%, 26/36), respectively. ConclusionsCACNA1F Gene variant eye diseases had diverse clinical phenotype. Clinical phenotype of PLAHF nystagmus is closely related with CACNA1F gene variant eye disease.
Tremor is an involuntary and repetitive swinging movement of limb, which can be regarded as a periodic disturbance in tremor suppression system based on functional electrical stimulation (FES). Therefore, using repetitive controller to adjust the level and timing of FES applied to the corresponding muscles, so as to generate the muscle torque opposite to the tremor motion, is a feasible means of tremor suppression. At present, most repetitive control systems based on FES assume that tremor is a fixed single frequency signal, but in fact, tremor may be a multi-frequency signal and the tremor frequency also varies with time. In this paper, the tremor data of intention tremor patients are analyzed from the perspective of frequency, and an adaptive repetitive controller with internal model switching is proposed to suppress tremor signals with different frequencies. Simulation and experimental results show that the proposed adaptive repetitive controller based on parallel multiple internal models and series high-order internal model switching can suppress tremor by up to 84.98% on average, which is a significant improvement compared to the traditional single internal model repetitive controller and filter based feedback controller. Therefore, the adaptive repetitive control method based on FES proposed in this paper can effectively address the issue of wrist intention tremor in patients, and can offer valuable technical support for the rehabilitation of patients with subsequent motor dysfunction.
ObjectiveTo evaluate the magnetic resonance imaging (MRI) manifestations, pathological and clinical characteristics, and treatment outcomes of multiple sclerosis (MS) patients with new lesion in medulla oblongata (MO).MethodsPubMed, EBSCO, and Springer databases between January 1st, 2000 and May 1st, 2018 were searched with the combined keywords of " multiple sclerosis” and " medulla oblongata”. Furthermore, the MS patients’ MRI manifestations, pathological and clinical characteristics, and treatment outcomes were summarized.ResultsA total of 18 papers were involved, in which 26 patients were included. The lesions in MO were mainly showed by wedge-shape (9/20), and round or oval-shape (9/20) in axial head MRI. Inflammatory cells infiltration and acute demyelination in the new lesions of MO had been displayed by autopsy reports of two MS patients. The new lesions in MO mainly referred to various types of nystagmus (9/26), left ventricular apical ballooning syndrome (LVABS) (8/26), neurogenic pulmonary edema (NPE) (6/26), and acute heart failure (6/26). Nucleus tracts solitaries (NTS), along with dorsal motor nucleus of the vagus nerve and medial reticular formation (MRF), was related to LVABS and NPE. Intercalatus nucleus, Roller nucleus and/or autonomic nerve structure were related to various types of nystagmus.ConclusionsIn axial head MRI, the new MS lesions in MO were mainly wedge-shape and round or oval-shape. Beyond that, the new MS lesions in MO could involve NTS, dorsal motor nucleus of the vagus nerve, MRF, intercalatus nucleus, Roller nucleus and/or autonomic nerve structure, resulting in special clinical features, such as, nystagmus, LVABS, NPE, and acute heart failure. Corticosteroid is still the main treatment to relieve the clinical manifestations caused by new MS lesions in MO.
Pathological neural activity in subthalamic nucleus (STN) is closely related to the symptoms of Parkinson's disease. Local field potentials (LFPs) recordings from subthalamic nucleus show that power spectral peaks exist at tremor, double tremor and tripble tremor frequencies, respectively. The interaction between these components in the multi-frequency tremor may be related to the generation of tremor. To study the linear and nonlinear relationship between those components, we analyzed STN LFPs from 9 Parkinson's disease patients using time frequency, cross correlation, Granger casuality and bi-spectral analysis. Results of the time-frequency analysis and cross-frequency correlation analysis demonstrated that the power density of those components significantly decreased as the alleviation of tremor and cross-correlation (0.18~0.50) exists during tremor period. Granger causality of the time-variant amplitude showed stronger contribution from tremor to double tremor components, and contributions from both tremor and double tremor components to triple tremor component. Quadratic phase couplings among these three components were detected by the bispectral approaches. The linear and nonlinear relationships existed among the multi-components and certainly confirmed that the dependence cross those frequencies and neurological mechanism of tremor involved complicate neural processes.
An automatic control system was designed to suppress pathological tremor on wrist joint with two degrees of freedom (DoF) using functional electrical stimulation (FES). The tremor occurring in the wrist flexion-extension and adduction-abduction was expected to be suppressed. A musculoskeletal model of wrist joint was developed to serve as the control plant, which covered four main muscles (extensor carpi radialis longus, extensor carpi ulnaris, flexor carpi radialis, and flexor carpi ulnaris). A second-order mechanical impedance model was used to describe the wrist skeletal dynamics. The core work was to design the controller and a hybrid control strategy was proposed, which combined inverse model based on feed forward control and linear quadratic regulator (LQR) optimal control. Performance of the system was tested under different input conditions (step signal, sinusoidal signal, and real data of a patient). The results indicated that the proposed hybrid controller could attenuate over 94% of the tremor amplitude on multi-DoF wrist joint.
ObjectiveTo observe the clinical features of eyes in children with methylmalonic acidemia (MMA). MethodsA retrospective clinical case study. From June 2019 to June 2022, 13 children with MMA visited on the Department of Ophthalmology of Henan Children's Hospital were included in the study. The anterior segment and fundus were examined under surface or general anesthesia. Best corrected visual acuity (BCVA) and refraction were performed in 9 cases; fluorescein fundus angiography (FFA) was performed in 3 cases; flash electroretinogram (FERG) was performed in 6 cases; flash visual evoked potential (FVEP) was detected in 6 cases; optical coherence tomography (OCT) was performed in 3 cases. ResultsAmong the 13 pediatric patients with methylmalonic acidemia, 6 cases were male and 7 cases were female. The average age at first visit was 45 months. All cases suffered from hyperhomocysteinemia; 9 cases were with epilepsy; 2 cases were with infantile spasms; 11 cases were with stunting, 13 cases were with repeated pulmonary infection during growth period; 4 cases were with hydrocephalus; 1 cases was with hypertension and renal insufficiency. Genetic dectection results of 8 cases were recorded, MMACHC:c.609G>A:p.W203* mutation site was found in all cases. One case was accompanied by corneal ulcer. There were 10 cases with nystagmus, 4 cases with macular degeneration, 3 cases with hyperopic refractive error and esotropia. Nine cases underwent BCVA examination, BCVA was light perception-0.6. In OCT, 2 cases of 3 cases showed retinal thinning and photoreceptor cell layer atrophy in the macular area. In FFA, 2 cases of 3 cases showed circular transparent fluorescence in the macular area. Five cases of 6 cases who with FVEP had different degrees of P100 peak time delay and decreased amplitude, and 4 cases of 6 cases with FERG had decrease of a and b wave in light and dark adaptation. ConclusionsThe clinical phenotypes of eyes in children with MMA are various and the severity was different; most of them are accompanied by nystagmus, and the fundus lesions are common in the characteristic bovine eye like macular region. Those with macular disease have severe visual impairment.
In order to characterize the characteristics of pathological tremor of human upper limb, a simulation system of pathological tremor of human arm was provided and its dynamic response was analyzed. Firstly, in this study, a two-degree-of-freedom human arm dynamic model was established and linearized according to the arbitrary initial angle of joints. After solving the analytical solutions of steady-state responses of the joints, the numerical solution was used to verify it. The results of theoretical analysis show that the two natural frequencies of the developed dynamic model are 2.9 Hz and 5.4 Hz, respectively, which meet the characteristic frequency range of pathological tremors. Then, combined with the measured parameters of human arm, a tremor simulation system was built, and the measured results of joint responses are in good agreement with the theoretical and simulation analysis results, which verifies the effectiveness of the theoretical model. The results show that the human arm pathological tremor simulation system designed in this paper can characterize the frequency and response amplitude of the human upper limb pathological tremor. Moreover, the relevant research lays a theoretical foundation and experimental conditions for the subsequent development of wearable tremor suppression devices.
Objective To observe and analyze the clinical characteristics of children with autosomal dominant hereditary microcephaly with or without chorioretinopathy, lymphedema, or intellectual disability syndrome (MCLMR). MethodsA retrospective clinical study. In September 2023, the first patient and three family members (parents, brother) of MCLMR who were diagnosed through ophthalmic examination and genetic testing at Department of Ophthalmology of Henan Children's Hospital were included in the study. Clinical data were collected, inquired about medical history and family history in detail, and performed best corrected visual acuity (BCVA), optical coherence tomography (OCT), fluorescein angiography (FFA), flash visual evoked potential (F-VEP), full field electroretinogram (ERG), cranial magnetic resonance imaging (MRI), and systemic examination. 3 ml of peripheral venous blood were collected from the proband, her parents and younger brother, and extracted whole genome DNA. Second generation sequencing technology was used for gene sequencing. For suspected pathogenic sites, Sanger sequencing was used for validation, and bioinformatics analysis was performed to determine the pathogenicity of the genetic variant sites. The relevant literature of PubMed of the National Library of Medicine and Wan Fang Med Online by computer were searched. The genetic characteristics and conducted literature review were summarized. ResultsThe proband (Ⅱ-1) was an 8-year-old and 5-month-old female. Her head was relatively small, the lower jaw was small, the ears protrude, the nose was wide, the eyelid was tilted upwards, philtrum was long. Mild intellectual disability, no history of lymphedema. The BCVA values for the right and left eyes were 0.08 and 0.1, respectively. Bilateral nystagmus. Atrophic lesioned in the macular area and below choroid retina of both eyes. FFA examination showed mottled fluorescent staining in the macular area and the below retina, with no obvious fluorescein leakage in the late stage. OCT examination revealed shallow macular fovea morphology, absence of ellipsoidal bands, unclear layers, thinning of the entire retina, and significant atrophy of the choroid and retina beneath the macula. F-VEP examination, no waveform was detected in both eyes. Full field ERG examination showed severe reduction in amplitude of a wave and b wave in both eyes. Head magnetic resonance imaging showed widening of the subarachnoid space in the left temporal region, with no significant abnormal signals observed in the brain parenchyma. Her father (Ⅰ-1) had mild nystagmus and strabismus. The phenotypes of the eyes of the mother (Ⅰ-2) and brother (Ⅱ-2) were not significantly abnormal. The genetic testing results showed that the proband (Ⅱ-1) had a heterozygous missense mutation c.895A>G (p.Ile299Val) in exon 8 of the KIF11 gene, which was a known mutation. Her parents (Ⅰ-1, Ⅰ-2) and younger brother (Ⅱ-2) were both wild-type. The bioinformatics analysis results indicated that this mutation is a potentially pathogenic variant. A total of 109 cases were retrieved from 20 relevant literatures. Among them, 55 were male, 54 were females. There were 61 cases with family history and 48 cases without family history, respectively. Among the 109 cases, 98 cases (89.9%, 98/109) had microcephaly, 2 cases had premature closure of cranial sutures, and 11 patients underwent cranial MRI, which showed 11 cases of small head with simplified development of the cerebral gyrus. 50 cases (45.9%, 50/109) of lymphedema. 83 cases (76.1%, 83/109) of intellectual developmental disorders. 92 cases (84.4%, 92/109) had ocular abnormalities, 69 cases (63.3%, 69/109) had chorioretinopathy, 20 cases (18.3%, 20/109) had retinal folds, 10 cases (9.2%, 10/109) had nystagmus, and 17 cases (15.6%, 17/109) had retinal detachment. ConclusionsThe main clinical manifestations of MCLMR are microcephaly, chorioretinopathy, with or without lymphedema, and intellectual disability. The main manifestations of eye diseases are low vision, nystagmus, and chorioretinopathy. The heterozygous missense mutation c.895A>G (p.Ile299Val) in exon 8 of KIF11 gene is the pathogenic variant of this family.