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We evaluated genetic variation in Middle East respiratory syndrome coronavirus (MERS-CoV) imported to South Korea in 2018 using specimens from a patient and isolates from infected Caco-2 cells. The MERS-CoV strain in this study was genetically similar to a strain isolated in Riyadh, Saudi Arabia, in 2017.

Objectives: Between November 20, 2016 and April 17, 2017, outbreaks of highly pathogenic avian influenza (HPAI) A/H5N6 occurred on poultry farms in Gyeonggi Province in the Republic of Korea. A serosurvey was conducted among poultry farmers to identify the transmission of HPAI A/H5N6 virus to humans. Methods: A descriptive study of 870 poultry farmers in Gyeonggi Province in Korea was conducted during the 2016–2017 outbreaks. Serological testing was performed using a microneutralization (MN) assay for antibodies against influenza A/duck/ES2/Korea/2016 virus, which has antigenic properties similar to those of the HPAI A/H5N6 virus that caused this poultry outbreak. Results: Overall, 523 exposed poultry farmers were assessed by serological testing. Consequently, all tested negative for HPAI A/H5N6 virus via MN assay. Conclusions: Based on serological assays, no transmission of HPAI A/H5N6 to humans was identified in this study cohort. Additional studies should be conducted to determine the possibility of poultry-to-human transmission of HPAI A/H5N6. Keywords: Avian influenza, H5N6, Poultry, Transmission, Korea

Outbreaks of avian influenza virus H5N8 first occurred in 2014, and spread to poultry farms in Korea. Although there was no report of human infection by this subtype, it has the potential to threaten human public health. Therefore, we evaluated the pathogenesis of H5N8 viruses in ferrets. Two representative Korean H5N8 strains did not induce mortality and significant respiratory signs after an intranasal challenge in ferrets. However, ferrets intratracheally infected with A/broiler duck/Korea/Buan2/2014 virus showed dose-dependent mortality. Although the Korean H5N8 strains were classified as the HPAI virus, possessing multiple basic amino acids in the cleavage site of the hemagglutinin sequence, they did not produce pathogenesis in ferrets challenged intranasally, similar to the natural infection route. These results could be useful for public health by providing the pathogenic characterization of H5N8 viruses.

Creutzfeldt-Jakob disease (CJD), included in the human transmissible spongiform encephalopathies (TSE), is widely known to be caused by an abnormal accumulation of misfolding prion protein in the brain. Human prion protein gene (PRNP) is mapped in chromosome 20p13 and many single nucleotide polymorphisms (SNPs) in PRNP have been discovered. However, the functionality of SNPs in PRNP is yet unclear, though several SNPs have been known as important mutation related with susceptibility human prion diseases. Our aim is to identify specific genotype patterns and characteristics in the PRNP genomic region and to understand susceptibility among Korean discriminated prion disease patients, suspected CJD patients and the KARE data group. Here, we have researched genotypes and SNPs allele frequencies in PRNP in discriminated prion disease patients group (n = 22), suspected prion diseases patients group (n = 163) and the Korea Association REsource (KARE) data group (n = 296) in Korea. The sequencing regions were promoter region, exon1 and exon2 with their junction parts among 481 samples. A total of 25 SNPs were shown in this study. Nucleotide frequencies of all SNPs are exceedingly tended to bias toward dominant homozygote types except in rs2756271. Genotype frequencies at codon 129 and 219 coding region were similar with previous studies in Korea and Japan. Pathogenic mutations such as 102P/L, 200E/K and 203V/I were observed in discriminated CJD patients group, and 180V/I and 232M/R were shown in suspected prion disease patients group and the KARE data group. A total of 10 SNPs were newly identified, six in the promoter region, one in exon 2 and three in the 3' UTR. The strong and unique linkage disequilibrium (D' = 0.94, r (2) = 0.89) was observed between rs57633656 and rs1800014 which is located in codon 219 coding region. We expect that these data can be provided to determine specific susceptibility and a protective factor of prion diseases not only in Koreans but also in East Asians.

We analyzed the proteomic profile of ME7 scrapie-infected mouse brains, and the interactions and functions of selected differentially expressed proteins to identify potential new biomarkers to be applicable for the diagnosis of Prion diseases. Mice were intracerebrally inoculated with 10% homogenate of ME7 scrapie-infected mouse brains, and monitored for neurological symptoms. We screened for proteins specifically expressed in infected brain samples using one-dimensional gel electrophoresis and liquid chromatography-mass spectrometry. 317 proteins based on their peptide scores and ratio values were selected. The major biological processes identified were cellular and metabolic processes, localization, and transport. Selected proteins had functions related to neurological processes, including cell-cell signaling, transmission of nerve impulse, and synaptic transmission. We analyzed infected host cells using experimental and computational methods, and found many significant protein expression changes. We identified 43 candidate proteins with high peptide scores and ratio values. Of these, 36 potential candidate proteins were related to up regulated biological processes, and 7 to down regulated biological processes. We confirmed the presence of two of these differentially expressed candidate proteins using immunoblotting.

Background: Human prion diseases are caused by abnormal accumulation of misfolded prion protein in the brain tissue. Inherited prion diseases, including familial Creutzfeldt-Jakob disease (fCJD), are associated with mutations of the prion protein gene (PRNP). The glutamate (E)-to-lysine (K) substitution at codon 200 (E200K) in PRNP is the most common pathogenic mutation causing fCJD, but the E200K pathogenic mutation alone is regarded insufficient to cause prion diseases; thus, additional unidentified factors are proposed to explain the penetrance of E200K-dependent fCJD. Here, exome differences and biological network analysis between fCJD patients with E200K and healthy individuals, including a non-CJD individual with E200K, were analysed to gain new insights into possible mechanisms for CJD in individuals carrying E200K. Methods: Exome sequencing of the three CJD patients with E200K and 11 of the family of one patient (case1) were performed using the Illumina HiSeq 2000. The exome sequences of 24 Healthy Koreans were used as control. The bioinformatic analysis of the exome sequences was performed using the CLC Genomics Workbench v5.5. Sanger sequencing for variants validation was processed using a BigDye Terminator Cycle Sequencing Kit and an ABI 3730xl automated sequencer. Biological networks were created using Cytoscape (v2.8.3 and v3.0.2) and Pathway Studio 9.0 software. Results: Nineteen sites were only observed in healthy individuals. Four proteins (NRXN2, KLKB1, KARS, and LAMA3) that harbour rarely observed single-nucleotide variants showed biological interactions that are associated with prion diseases and/or prion protein in our biological network analysis. Conclusion: Through this study, we confirmed that individuals can have a CJD-free life, even if they carry a pathogenic E200K mutation. Our research provides a possible mechanism that involves a candidate protective factor; this could be exploited to prevent fCJD onset in individuals carrying E200K.

Introduction Pectus excavatum is the most common congenital chest wall deformity and the depression of the anterior chest wall, which compresses the internal organs. The aim of the present study is to investigate the effects of pectus excavatum on blood laboratory findings. Material and Methods From March 2011 to December 2011, 71 patients with pectus excavatum who visited Seoul Saint Mary Hospital for Nuss procedure were reviewed and analyzed. The blood samples were routinely taken at the day before surgery and pectus bar removal was usually performed in 2 to 3 years after Nuss procedure. To investigate the effects on blood laboratory findings, preoperative routine blood laboratory data and postoperative changes of abnormal laboratory data were analyzed. Results Only lactate dehydrogenase (LDH), one of 26 separate routine laboratory tests, was abnormal and significantly elevated than normal value (age

Background Polymorphisms of the human prion protein gene (PRNP) contribute to the genetic determinants of Creutzfeldt-Jakob disease (CJD). Numerous polymorphisms in the promoter regions as well as the open reading frame of PRNP were investigated. Greater than 90% of Korean, Chinese, and Japanese carry the homozygote 129 MM codon. In Korea, polymorphisms have not been comprehensively studied, except codons 129 and 219 in PRNP among Korean CJD cases. Although polymorphisms at codons 129 and 219 play an important role in susceptibility to sporadic CJD, patients with other polymorphisms in PRNP exhibited critical distinctions of clinical symptoms. Methods The genetic analyses of PRNP were carried out among probable CJD patients in comparison with the results from magnetic resonance imaging (MRI) and electroencephalogram (EEG). Results The molecular analyses revealed that three mutations at codons D178N, E200K, and M232R in heterozygosity. Patients with the D178N and M232R mutations had a 129MM codon, whereas the patient with the E200K mutation showed 129MV heterozygosity. They all revealed strong 14-3-3 positive signals. The 67-year-old patient with the D178N-129M mutation showed progressive gait disturbance and dysarthria was in progress. The 58-year-old patient with the E200K mutation coupled to the 129MV codon had gait disturbance, dysarthria, agitation, and ataxic gait, and progressed rapidly to death 3 months from the first onset of symptoms. The 65-year-old patient with the M232R mutation showed rapidly progressive memory decline and gait disturbance, and died within 16 months after onset of symptoms. Conclusion Despite differences in ethnicity, the clinical and pathological outcomes were similar to the respective mutations around the world, except absence of insomnia in D178N-129M subject.

Several lines of prion protein gene (Prnp)-knockout mice such as ZrchI, ZrchII, Npu, Ngsk and Rcm0 have been generated. Of these, ZrchII, Ngsk and Rcm0 exhibit late-onset ataxia due to ectopic expression of Doppel (Dpl); a result of damage to the splicing acceptor of Prnp exon 3. Recently, we developed another line of Prnp-/- mice (Rikn), which was generated by gene targeting with more nucleotides by replacing intron 2 with the pgk-neo gene (cf. Ngsk Prnp-/- mice) and showed not only ataxia but also a lower olfactory sensitivity than the other Prnp-/- mouse line ZrchI at over 60 weeks of age. The histopathology of the elderly Rikn Prnp-/- mice showed mitral cell loss concomitantly observed with gliosis of astrocytes. Western blot analysis showed that Dpl was detected in the cerebrum, cerebellum and olfactory bulb of Rikn Prnp-/- mice, where aberrant histopathology was observed. Thus, mitral cell loss and gliosis induced by ectopic Dpl expression were probably associated with the late-onset olfactory deficits in Rikn Prnp-/- mice.

Eight major policies were implemented by Japanese Government since Oct. 2001, to deal with bovine spongiform encephalopathy (BSE). These are; 1) Surveillance in farm by veterinarian, 2) Prion test at healthy 1.3mi cows/yr, by veterinarian, 3) Elimination of specified risk material (SRM), 4) Ban of MBM for production, sale use, 5) Prion test for fallen stocks, 6) Transparent information and traceability, 7) New Measures such as Food Safety Basic Law, and 8) Establish of Food Safety Commission in the Cabinet Office. At this moment, the extent of SRM risk has only been indicated by several reports employing tests with a limited sensitivity. There is still a possibility that the items in the SRM list will increase in the future, and this indiscriminately applies to Japanese cattle as well. Although current practices of SRM elimination partially guarantee total food safety, additional latent problems and imminent issues remain as potential headaches to be addressed. If the index of SRM elimination cannot guarantee reliable food safety, we have but to resort to total elimination of tissues from high risk-bearing and BSE-infected animals. However, current BSE tests have their limitations and can not yet completely detect high-risk and/or infected animals. Under such circumstances, tissues/wastes and remains of diseased, affected fallen stocks and cohort animals have to be eliminated to prevent BSE invading the human food chain systems. The failure to detect any cohort should never be allowed to occur, and with regular and persistent updating of available stringent records, we are at least adopting the correct and useful approach as a reawakening strategy to securing food safety. In this perspective, traceability based on a National Identification System is required.

With the aim of establishing bio-indices for the development of multistep hepatotumorigenesis, rats were fed water containing 0.01% diethylnitrosamine (DEN) ad libitum for 13 weeks. This treatment with DEN only made it possible to induce hepatic tumors in 100%. After the DEN administration, several clinical symptoms were observed including minor behavioral changes, brittleness of hair and a decrease in water and food intake. The concentration of total serum protein and albumin in all treated groups was significantly lower than in non-treated controls (P