Objective To observe the gene mutation and clinical phenotype of patients with retinitis pigmentosa (RP) and cone rod dystrophy (CORD). Methods Thirty-seven patients with RP and 6 patients with CORD and 95 family members were enrolled in the study. The patient’s medical history and family history were collected. All the patients and family members received complete ophthalmic examinations to determine the phenotype, including best corrected visual acuity, slit lamp microscope, indirect ophthalmoscopy, color fundus photography, optical coherence tomography, full-field electroretinogram, and fluorescein fundus angiography. DNA was abstracted from patients and family members. Using target region capture sequencing combined with next-generation sequencing to screen the 232 candidate pathogenic mutations. Polymerase chain reaction and direct sequencing were used to confirm the pathogenic pathogenic mutations and Co-segregation is performed among members in the family to determine pathogenic mutation sites. The relationship between genotype and clinical phenotype of RP and CORD was analyzed. Results Of the 37 patients with RP, 13 were from 6 families, including 4 families with autosomal dominant inheritance, 2 families with autosomal recessive inheritance, and 3 in 6 families were detected pathogenic gene mutations. 24 cases were scattered RP. Six patients with CORD were from four families, all of which were autosomal recessive. Of the 43 patients, 21 patients were detected the pathogenic gene mutation, and the positive rate was 48.8%. Among them, 15 patients with RP were detected 10 pathogenic gene mutations including USH2A, RP1, MYO7A, C8orf37, RPGR, SNRNP200, CRX, PRPF31, C2orf71, IMPDH1, and the clinical phenotype included 10 typical RP, 2 cases of RPSP, 3 cases of Usher syndrome type 2 and 6 cases of CORD patients were all detected pathogenic gene mutations, including 2 cases of ABCA4, 2 mutations of RIMS1 gene, 1 case of CLN3 gene mutation, and 1 case of CRB1 and RPGR double gene mutation. Conclusions RP and CORD are clinically diverse in genotype and clinically phenotypically similar. For patients with early RP and CORD, clinical phenotype combined with genetic analysis is required to determine the diagnosis of RP and CORD.
Existing neuroregulatory techniques can achieve precise stimulation of the whole brain or cortex, but high-focus deep brain stimulation has been a technical bottleneck in this field. In this paper, based on the theory of negative permeability emerged in recent years, a simulation model of magnetic replicator is established to study the distribution of the induced electric field in the deep brain and explore the possibility of deep focusing, which is compared with the traditional magnetic stimulation method. Simulation results show that a single magnetic replicator realized remote magnetic source. Under the condition of the same position and compared with the traditional method of stimulating, the former generated smaller induced electric field which sharply reduced with distance. By superposition of the magnetic field replicator, the induced electric field intensity could be increased and the focus could be improved, reducing the number of peripheral wires while guaranteeing good focus. The magnetic replicator model established in this paper provides a new idea for precise deep brain stimulation, which can be combined with neuroregulatory techniques in the future to lay a foundation for clinical application.
Objective To evaluate the effectiveness of using pedical screw at the fracture level, intervertebral distraction, and Cage insertion by posterior approach to treat thoracolumbar kyphosis caused by old fracture. Methods Between June 2008 and June 2010, 15 cases of thoracolumbar kyphosis caused by old fracture were treated with pedical screw at the fracture level, intervertebral distraction, and Cage insertion by posterior approach. There were 9 males and 6 females with a mean age of 54.6 years (range, 39-65 years). The disease duration was 5 months to 3 years with an average of 1.5 years. Fractured segments included T11 in 1 case, T12 in 4 cases, L1 in 5 cases, and L2 in 5 cases. Ten patients had nerve symptom, according to American Spinal Injury Association (ASIA) grading, 3 cases were classified as grade B, 4 cases as grade C, and 3 cases as grade D, of which 3 cases had sexual and sphincter dysfunction. At preoperation, the Cobb angle was (47.4 ± 10.2)°; the Oswestry disability index (ODI) score was 67.9% ± 6.9%; and the visual analogue scale (VSA) was 8.6 ± 1.4. Results The wounds obtained primary healing. The mean follow-up time was 28 months (range, 13-60 months). X-ray films showed intervertebral bone fusion was obtained within 6-11 months (mean, 10.2 months). No fixation loosening or breaking occurred during follow-up. Kyphosis was corrected, and lumbar back pain was relieved. At 1 year after operation, Cobb angle was significantly corrected to (13.3 ± 7.7)° (t=72.80, P=0.00); ODI score was significantly improved to 25.2% ± 4.6% (t=48.04, P=0.00); VAS score was significantly decreased to 2.3 ± 0.6 (t=26.52, P=0.00). According to ASIA grading in 10 patients with spinal cord injury, the spinal cord function was improved by 1 grade in 8 cases (3 cases from grade B to C, 3 cases from grade C to D, and 2 cases from grade D to E); 3 patients with sexual and sphincter dysfunction recovered in different degrees. Conclusion Using pedical screw at the fracture level, intervertebral distraction, and Cage insertion by posterior approach is an effective method to treat thoracolumbar kyphosis caused by old fracture.