Acute Necrotizing Myelitis Associated with COVID-19

Acute ascending hemorrhagic longitudinally extensive transverse myelitis is a rare inflammatory demyelinating disorder, which invades several vertebral segments and progresses rapidly and manifests severe symptoms. We present a case of acute necrotizing myelitis associated with COVID-19 infection. A 10-year-old female, with no previous medical history and no prior administration of COVID-19 vaccination, contracted COVID-19 in early April 2022. Two weeks later, she suffered from severe posterior neck pain and also presented with motor weakness and numbness in both lower extremities, making it difficult to walk independently and spontaneously void urine. Initial spinal cord MR showed longitudinally segmental extensive T2 hyperintensities. Cerebrospinal fluid (CSF) analysis revealed elevated red blood cell, normal white blood cell, and elevated protein levels and absence of oligoclonal bands. CSF culture and viral polymerase chain reaction were negative. Autoimmune work-up was negative. She was started on intravenous methylprednisolone 1g/day for 5 days and immunoglobulin (Ig) 2 g/kg for 5 days. She was also treated with six courses of therapeutic plasma exchange. Nevertheless, her pain and motor weakness persisted. She eventually developed respiratory failure. Follow-up MR presented a newly noted small hemorrhagic component. She was consequently treated with two additional courses of methylprednisolone and Ig. At 6-months follow-up, neurological examination showed improvement with normal sensory function and motor grade IV function in both upper extremities. We present the case of acute necrotizing myelitis associated with COVID-19 infection. Multiple courses of methylprednisolone and Ig showed mild improvement in motor and sensory function. However, poor prognosis was unavoidable due to rapid progression of the disease.

Coexisting Rheumatoid Arthritis and Takayasu's Arteritis: a Case Report and Review of the Literature

The coexistence of rheumatoid arthritis (RA) and Takayasu's arteritis (TA) is a rare combination and described only in case reports in the literature. Although concurrent presence of RA and TA has been described only in a few literatures to date and the number of reports is increasing, the association between RA and TA remains to be clarified. We present a case of a female patient with both RA and TA, presenting with polyarthritis. We also reviewed the clinical features of the cases with coexistence of RA and TA.

Laser Capture Microdissection Reveals Specific Genes Related to Purkinje Cell Death in the Leaner Mice / 한국실험동물학회지

The leaner mouse carries a mutation in the gene encoding the alpha1A subunit of P/Q-type calcium channels. Leaner mice exhibit extensive cerebellar granule and Purkinje cell loss that results in cerebellar dysfunction. A previous study suggested that a small population of leaner Purkinje cells undergo apoptosis, however the cell death mode of the rest of degenerating Purkinje cells has not been identified. In order to investigate the mechanisms underlying leaner Purkinje cell death, gene arrays that contain 243 cell death related genes were carried out. To increase the chance of detecting Purkinje cell specific genes, laser capture microdissection was employed to obtain Purkinje cell enriched samples. The gene array analysis revealed several potential genes that are involved in autophagic cell death pathway including cathepsin D, a key lysosomal protease that triggers autophagic degradation. Further analysis on LC3, which is a hallmark for autophagic cell death showed that leaner Purkinje cells are degenerating via autophagic process. The present study provides evidence that calcium channel defects trigger different modes of neurodegeneration in the cerebellum.

Laser Capture Microdissection Reveals Specific Genes Related to Purkinje Cell Death in the Leaner Mice / 한국실험동물학회지

The leaner mouse carries a mutation in the gene encoding the alpha1A subunit of P/Q-type calcium channels. Leaner mice exhibit extensive cerebellar granule and Purkinje cell loss that results in cerebellar dysfunction. A previous study suggested that a small population of leaner Purkinje cells undergo apoptosis, however the cell death mode of the rest of degenerating Purkinje cells has not been identified. In order to investigate the mechanisms underlying leaner Purkinje cell death, gene arrays that contain 243 cell death related genes were carried out. To increase the chance of detecting Purkinje cell specific genes, laser capture microdissection was employed to obtain Purkinje cell enriched samples. The gene array analysis revealed several potential genes that are involved in autophagic cell death pathway including cathepsin D, a key lysosomal protease that triggers autophagic degradation. Further analysis on LC3, which is a hallmark for autophagic cell death showed that leaner Purkinje cells are degenerating via autophagic process. The present study provides evidence that calcium channel defects trigger different modes of neurodegeneration in the cerebellum.

Haplotypes and mutations of 17 Y-STR loci from Korean father-son pairs / 대한법의학회지

We have investigated 17 Y-STR loci (DYS19, DYS385a/b, DYS389-I, DYS389-II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 (Y GATA C4), Y GATA H4) in 365 Korean father-son pairs of 355 families. Of 338 different haplotypes obtained from 355 fathers, 326 haplotypes were observed once, 10 haplotypes two times and the other two haplotypes were observed 4 and 5 times, respectively. The overall haplotype diversity was 0.9996. In 365 father-son pairs, a total of 21 mutations were observed at 12 Y-STR loci. Sequence analysis for mutant alleles demonstrated 21 single step mutations: 8 gains and 13 losses. However, there was no significant surplus of gains or losses. The locus-specific mutation rate estimates were between 0.0 and 8.2 x 10(-3) and the average mutation rate estimates were 3.4 x 10(-3)(95% C.I. 2.1-5.2 x 10(-3)) across all 17 Y-STR loci.

Intra-individual Difference of Length Heteroplasmy in Blood and Hair Shaft Mitochondrial DNA / 대한법의학회지

To observe mtDNA length heteroplasmy in a homoploymeric cytosine tract of the mitochondrial HV2 region, we carried out size-based separation of PCR products, which was produced by using primers designed to minimize the stutter production. Blood and hair shaft samples were collected from 25 individuals. The result showed significant qualitative/quantitative peak pattern variations among blood and hair shaft mtDNA profiles. Based on the results of this study, an exclusion depended solely on differences in length of the major C-tract variant could thus be an erroneous interpretation. Therefore, differences in the number of cytosine or qualitative/quantitative peak pattern variations in the C-tract of the mtDNA HV2 region cannot be used alone to support an interpretation of exclusion.

A Population Study of X-chromosomal STRs, DXS9898, DXS6809, DXS7424 and DXS10011 in Koreans / 대한법의학회지

A population study of the X-chromosomal short tandem repeat (STR) loci DXS9898, DXS6809, DXS7424 and DXS10011 was carried out by single multiplex PCR in a sample of 300 unrelated Korean individuals (150 males and 150 females). For accurate and reproducible STR typing, sequenced allelic ladders were constructed and GenoTyper macro was programmed. In this study, four types of the repre-sentative repeat sequence structure of DXS10011 were observed and the allele loss at DXS9898 was observed in 13 of 450 chromosomes (2.9%). The inter-population comparison of the allele frequencies at the 4 X-STRs showed significantly different distributions (p<0.01) for Koreans and Germans except DXS10011. All statistical parameters for forensic efficiency showed that the 4 X-chromosomal STRs are highly informative. Especially, DXS10011 is expected to be the most useful marker for forensic practice.

Simple Quantification and DNA Profiling from Degraded Low Copy Number DNA Samples / 대한법의학회지

DNA quantification is important to ensure the consistency and the reliability in the interpretation of degraded low copy number DNA typing. We applied the simple PCR quantification method using fluo-rescently labeled primers for the amplification of mtDNA and amelogenin gene in 50 year old skeletal remains (e.g. bone and tooth). K562 DNA was serially diluted and used as a standard for concentration marker to gauge the amount of DNA from PCR versus the peak area. The quantities of DNA extracted from bones and teeth did not show significant difference in the analyses both using mtDNA and amelo-genin gene as an amplification target. To test the efficiency of DNA profiling of degraded low copy number DNA samples, mtDNA PCR quality evaluation and DNA typing for 16 autosomal STR and 9 Y chromosomal STR loci were per-formed and the correlation between DNA quantities and PCR amplification efficiencies of the samples was analyzed. The DNA quantities assayed by the simple method suggested in the present study could be good indicator for mtDNA and STR analysis. As the allele drop-out was observed in less than 0.050ng DNA samples, at least 0.100ng of DNA is required to produce informative STR profiles. Also, STRs with less than 200bp amplification sizes produce efficient DNA profiles in most cases. Therefore, the develop-ment of mini-STRs with less than 200bp amplification sizes is expected to improve DNA typing in degraded low copy number DNA. Y-STRs are easy to detect allele drop-out or drop-in, and accordingly the efficiency test of Y-STRs as well as autosomal STRs for profiling of degraded low copy number DNA samples is thought to be important.