• Journal of Genetic Medicine
• /
• v.10 no.1
• /
• pp.13-19
• /
• 2013

Retinitis pigmentosa (RP) is the most common hereditary retinal disorder and is characterized by progressive retinal degeneration and decline in vision. RP comprises a heterogeneous group of disorders caused by various genetic variants. Since the first discovery of the causal mutation in the RHO gene using positional cloning, numerous mutations have been detected in more than 60 loci and 50 genes. However, causal genes have not been discovered in about 50% of cases. We attempt here to review the strategies to identify causal alleles of retinitis pigmentosa. These include conventional methods as well as state-of-the-art technologies based on next-generation sequencing.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.19 no.3 s.31
• /
• pp.224-231
• /
• 2006

Retinitis pigmentosa(RP) is characterized by night-blindness, contraction of the visual field, distinct hereditary nature, wide-spread pigmentary in the midperiphery. We have experienced a case of retinitis pigmentosa treated by oriental medicine (Herbal medicaiton, Acupuncture & Electroacupuncture therapy). In the point of Differentiation of syndrome, this subject was diagnosed deficiency of both Gi & blood and Eum deficiency of Liver and Kidney. So we was administrated with Palmultang-Gamibang. After treatment of orient medicine, symptoms of patient were improved.

• Investigative Magnetic Resonance Imaging
• /
• v.22 no.2
• /
• pp.119-122
• /
• 2018

Neurogenic weakness, ataxia and retinitis pigmentosa (NARP) syndrome is a rare maternally inherited mitochondrial disorder. Radiologic findings in NARP syndrome are varied; they include cerebral and cerebellar atrophy, basal ganglia abnormalities, and on rare occasions, leukoencephalopathy. This article describes an extremely rare case of NARP syndrome mimicking mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS).

• Journal of Korea Multimedia Society
• /
• v.15 no.6
• /
• pp.701-710
• /
• 2012

Retinitis Pigmentosa(RP) is a common hereditary disease. While they have been normally living, those who have this symptom feel frustration and pain by the damage of visual acuity. At the national level, the loss of the economic activity due to the reduction of economically active population will be also greater. There is an urgent need for the base study that can provide the clinical prognosis information of RP disease. In this study, we suggest that it is possible to predict prognosis through the pattern classification of RP data. Statistical processing results through statistical software like SPSS(Statistical Package for the Social Service) were mainly applied for the conventional study in data analysis. However, machine learning and automatic pattern classification was applied to this study. SVM(Support Vector Machine) and other various pattern classifiers were used for it. The proposed method confirmed the possibility of prognostic prediction based on the result of automatically classified RP data by SVM classifier.

• Childhood Kidney Diseases
• /
• v.2 no.2
• /
• pp.200-203
• /
• 1998

The Laurence Moon-Bardet Biedl syndrome is characterized by obesity, mental retardation, visual impairment with retinitis pigmentosa, polydactyly, hypogonadism and renal manifestations. We experienced an 11 years old female with Laurence Moon-Baret Biedl syndrome associated chronic renal failure. She was diagnosed to have LMB syndrom according to the clinical manifestations of polydactyly on hands and feet, mental retardation, obesity, retinitis pigmentosa and chronic renal failure. She is on maintenance hemodialysis now.

• The Korean Journal of Physiology and Pharmacology
• /
• v.17 no.3
• /
• pp.229-235
• /
• 2013

Among several animal models of retinitis pigmentosa (RP), the more recently developed rd10 mouse with later onset and slower rate of retinal degeneration than rd1 mouse is a more suitable model for testing therapeutic modalities. We therefore investigated the time course of retinal degeneration in rd10 mice before adopting this model in our interventional studies. Electroretinogram (ERG) recordings were carried out in postnatal weeks (PW) 3~5 rd10 (n=23) and wild-type (wt) mice (n=26). We compared the amplitude and implicit time of the b-wave of ERG records from wt and rd10 mice. Our results showed that b-wave amplitudes in rd10 mice were significantly lower and the implicit time of b-waves in rd10 mice were also significantly slower than that in wt mice ($20{\sim}160{\mu}V$ vs. $350{\sim}480{\mu}V$; 55~75 ms vs. 100~150 ms: p<0.001) through PW3 to PW5. The most drastic changes in ERG amplitudes and latencies were observed during PW3 to PW4. In multichannel recording of rd10 retina in PW2 to PW4.5, we found no significant difference in mean spike frequency, but the frequency of power spectral peak of local field potential at PW3 and PW3.5 is significantly different among other age groups (p<0.05). Histologic examination of rd10 retinae showed significant decrease in thickness of the outer nuclear layer at PW3. TUNEL positive cells were most frequently observed at PW3. From these data, we confirm that in the rd10 mouse, the most precipitous retinal degeneration occurs between PW3~PW4 and that photoreceptor degeneration is complete by PW5.

• Journal of Interdisciplinary Genomics
• /
• v.5 no.1
• /
• pp.5-11
• /
• 2023

β-ureidopropionase (β-UP) is an enzyme that catalyzes the final step in the pyrimidine degradation pathway, which converts β-ureidopropionate and β-ureidoisobutyrate into β-alanine and β-aminoisobutyrate, respectively. β-UP deficiency (UPB1D; OMIM # 613161) is an extremely rare autosomal recessive inborn error disease caused by a mutation in the UPB1 gene on chromosome 22q11. To date, approximately 40 cases of UPB1D have been reported worldwide, including one case in Korea. The clinical manifestations of patients with UPB1D are known to be diverse, with a very wide range of manifestations being previously reported; these manifestations include completely asymptomatic, urogenital and colorectal anomalies, or severe neurological involvement, including global developmental delay, microcephaly, early onset psychomotor retardation with dysmorphic features, epilepsy, optic atrophy, retinitis pigmentosa, severely delayed myelination, and cerebellar hypoplasia. Currently, diagnosis of UPB1D is challenging as neurological manifestations, MRI abnormalities, and biochemical analysis for pyrimidine metabolites in the urine, plasma, and cerebrospinal fluid also need to be confirmed by UPB1 gene mutations. Overall, treatment of patients with UPB1D is palliative as there is still no definitive curative treatment available.

• Childhood Kidney Diseases
• /
• v.11 no.1
• /
• pp.112-117
• /
• 2007

Although juvenile nephronophthisis(NPHP) is one of the most frequent genetic causes of chronic renal failure, it has very rarely been reported in Korean children. Most NPHP patients are found to have chronic renal failure, since there are no distinct clinical symptoms for NPHP except polydipsia, polyuria and enuresis in the early stage of disease. Ten percent of NPHP patients manifest retinitis pigmentosa, called $Senior-L\ddot{o}ken$ syndrome. We experienced 2 cases of $Senior-L\ddot{o}ken$ syndrome that occurred in siblings(a 10 year-old boy and a 14-year-old girl) who were diagnosed with Leber's amaurosis. They were found to have severe renal impairment without polydipsia and polyuria. However, no large homogenous deletion of the NPHPI(2q13) gene was not identified in these patients. We report here on these cases and we review the literature to emphasize the association between Leber's amaurosis and the development of chronic renal failure.

• The Korean Journal of Physiology and Pharmacology
• /
• v.12 no.6
• /
• pp.307-314
• /
• 2008

Retinal prostheses are being developed to restore vision for the blind with retinal diseases such as retinitis pigmentosa (RP) or age-related macular degeneration (AMD). Among the many issues for prosthesis development, stimulation encoding strategy is one of the most essential electrophysiological issues. The more we understand the retinal circuitry how it encodes and processes visual information, the greater it could help decide stimulation encoding strategy for retinal prosthesis. Therefore, we examined how retinal ganglion cells (RGCs) in in-vitro retinal preparation act together to encode a visual scene with multielectrode array (MEA). Simultaneous recording of many RGCs with MEA showed that nearby neurons often fired synchronously, with spike delays mostly within 1 ms range. This synchronized firing - narrow correlation - was blocked by gap junction blocker, heptanol, but not by glutamatergic synapse blocker, kynurenic acid. By tracking down all the RGC pairs which showed narrow correlation, we could harvest 40 functional connectivity maps of RGCs which showed the cell cluster firing together. We suggest that finding functional connectivity map would be useful in stimulation encoding strategy for the retinal prosthesis since stimulating the cluster of RGCs would be more efficient than separately stimulating each individual RGC.

• Journal of Biomedical Engineering Research
• /
• v.30 no.4
• /
• pp.347-354
• /
• 2009

For the reliable transmission of meaningful visual information using prosthetic electrical stimulation, it is required to develop an effective stimulation strategy for the generation of electrical pulse trains based on input visual information. The characteristics of neuronal activities of retinal ganglion cells (RGCs) evoked by electrical stimulation should be understood for this purpose. In this study, for the development of an optimal stimulation strategy for visual prosthesis, we analyzed the neuronal responses of RGCs in rd1 mouse, photoreceptor-degenerated retina of animal model of retinal diseases (retinitis pigmentosa). Based on the in-vitro model of epiretinal prosthesis which consists of planar multielectrode array (MEA) and retinal patch, we recorded and analyzed multiunit RGC activities evoked by amplitude-modulated electrical pulse trains. Two modes of responses were observed. Short-latency responses occurring at 3 ms after the stimulation were estimated to be from direct stimulation of RGCs. Long-latency responses were also observed mainly at 2 - 100 ms after stimulation and showed rhythmic firing with same frequency as the oscillatory background field potential. The long-latency responses could be modulated by pulse amplitude and duration. From the results, we expect that optimal stimulation conditions such as pulse amplitude and pulse duration can be determined for the successful transmission of visual information by electrical stimulation.