• Parasites, Hosts and Diseases
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• v.53 no.6
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• pp.699-703
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• 2015

Cystic echinococcosis (CE) is one of the most widespread zoonotic helminthiases, which can last an asymptomatic infection for several years. The purpose of this study was to demonstrate serum antibody prevalence of CE among asymptomatic people in Uzbekistan using ELISA. A total of 2,547 serum samples were collected, 66 from confirmed CE patients and 2,481 of patients with other diseases than CE at a hospital in Tashkent, Uzbekistan. The serum samples were screened for CE specific IgG antibodies by ELISA using cystic fluid antigen obtained from sheep. The serum antibody positive rate was 89.4% (59/66) in CE and 3.6% (89/2,481) in other disease patients. The present ELISA recognized 89.4% sensitivity and 96.4% specificity. The ELISA absorbance of positive samples was distributed 0.271-0.971 for CE and 0.273-0.887 for other disease patients. The other disease patients with high absorbance over 0.3 were 50 (2.0%) who were presumed to be active CE patients. The patients in their 40s showed the highest positive rate of 5.2% (P=0.181), and women were 4.4% while men were 3.1% positive (P=0.136). The data confirmed that there are many asymptomatic patients of CE in Tashkent. It is indicated that CE is an endemic disease of public health importance in Uzbekistan.

• Parasites, Hosts and Diseases
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• v.53 no.6
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• pp.689-697
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• 2015

The tapeworm Taenia solium is an important human zoonotic parasite that causes great economic loss and also endangers public health. At present, an effective vaccine that will prevent infection and chemotherapy without any side effect remains to be developed. In this study, codon usage patterns in the T. solium genome were examined through 8,484 protein-coding genes. Neutrality analysis showed that T. solium had a narrow GC distribution, and a significant correlation was observed between GC12 and GC3. Examination of an NC (ENC vs GC3s)-plot showed a few genes on or close to the expected curve, but the majority of points with low-ENC (the effective number of codons) values were detected below the expected curve, suggesting that mutational bias plays a major role in shaping codon usage. The Parity Rule 2 plot (PR2) analysis showed that GC and AT were not used proportionally. We also identified 26 optimal codons in the T. solium genome, all of which ended with either a G or C residue. These optimal codons in the T. solium genome are likely consistent with tRNAs that are highly expressed in the cell, suggesting that mutational and translational selection forces are probably driving factors of codon usage bias in the T. solium genome.

• Korean Journal of Veterinary Research
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• v.54 no.3
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• pp.147-150
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• 2014

Q-fever is a vector-borne (Coxiella [C.] burnetii) zoonotic disease that is an increasing public health concern. To date, some research about Q-fever prevalence in dairy herds and human patients has been reported in Korea, but information about Korean native cattle is scarce. To measure the prevalence rates of C. burnetii in Korean native cattle, a total of 1,095 bovine serum samples collected during 2010~2013 were analyzed with an enzyme-linked immunosorbent assay. Sixty-eight heads of cattle were diagnosed as positive and while 19 heads were suspected (positive rate = 6.2%). Interestingly, Jeju province had a seropositivity rate six times greater than that of other provinces (18.9% vs. 3.2%). High seroprevalence might be caused by wide distribution of ticks in Jeju province compared to other regions. Based on these data, extensive monitoring of C. burnetii infection in cattle, tick distribution, and climate changes is required.

• Parasites, Hosts and Diseases
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• v.44 no.1 s.137
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• pp.27-33
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• 2006

Two species of Cryptosporidium are known to infect man; C. hominis which shows anthroponotic transmission between humans, and C. parvum which shows zoonotic transmission between animals or between animals and man. In this study, we focused on identifying genotypes of Cryptosporidium prevalent among inhabitants and domestic animals (cattle and goats), to elucidate transmittal routes in a known endemic area in Hwasun-gun, Jeollanam-do, Republic of Korea. The existence of Cryptosporidium oocysts was confirmed using a modified ZiehlNeelsen stain. Human infections were found in 7 $(25.9\%)$ of 27 people examined. Cattle cryptosporidiosis cases constituted 7 $(41.2\%)$ of 17 examined, and goat cases 3 $(42.9\%)$ of 7 examined. Species characterizations were performed on the small subunit of the rRNA gene using both PCR-RFLP and sequence analysis. Most of the human isolates were mixtures of C. hominis and C. parvum genotypes and similar PCR-RFLP patterns were observed in cattle and goat isolates. However, sequence analyses identified only C. hominis in all isolates examined. The natural infection of cattle and goats with C. hominis is a new and unique finding in the present study. It is suggested that human cryptosporidiosis in the studied area is caused by mixtures of C. hominis and C. parvum oocysts originating from both inhabitants and domestic animals.

• Korean Journal of Veterinary Research
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• v.52 no.3
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• pp.193-198
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• 2012

Avian chlamydiosis is caused by Chlamydophila psittaci and considered as one of an important zoonotic disease throughout the world. Among more than 400 avian species including poultry and pet birds susceptible to the disease, psittacine birds were known to be mostly susceptible hosts. In Korea, no outbreak of the disease and genetic analysis of the agent in poultry and pet birds have been reported. With histopathological findings and genetic identification of a causative agent, avian chlamydiosis was identified in parrots submitted from the same pet bird farm in 2006 and 2009 for the diagnosis. Based on genetic sequences and phylogenetic analysis of ompA gene, the two isolates of Chlamydophila psittaci showed 100% of genetic similarity and belonged to genotype A, suggesting that the same agent might be continuously circulated in the farm. This result indicates that serological survey of the disease in pet bird farms and impact of the disease on significance in public health may be further studied.

• Korean Journal of Veterinary Research
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• v.57 no.1
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• pp.67-69
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• 2017

In the present study, Aeromonas (A.) hydrophila was isolated from a captive-bred adult freshwater stingray (Potamotrygon motoro) reared at a commercial aquarium in Korea. The stingray had bites on its fins, hemorrhages on the ventral part, and congested internal organs. A bacterium was isolated from kidney and subsequently identified as A. hydrophila. Based on phylogenetic analysis results, the isolate in the present study (SNUAh-LA1) was most closely related to A. hydrophila AH10 (China) and A. hydrophila AKR1 (Korea). It is most likely that the pathogen infection resulted from Potamotrygon motoro cohabiting with ricefish (Oryzias latipes).

• Korean Journal of Veterinary Service
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• v.31 no.2
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• pp.195-205
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• 2008

Yersinia enterocolitica is a zoonotic agent, and to cause food poisoning. This study was carried out to get some basic information for the control of Yersinia infection. A total of 1,680 samples were collected from beef and pork carcasses from January 2006 to December 2007 in Seoul. The isolation rate was higher in pork carcass than in beef carcass. Five (0.59%) Yersinia enterocolitica were isolated from the 840 of beef carcasses, and eighteen(2.14%) were isolated from the 840 of pork carcasses. Among 23 strains, 22 were classified into biotype 1A, and one was biotype 6. In serotyping of Y enterocolitica isolates, 21 strains were untypable (UT), and 2 were O5 and O8 respectively. In PCR, Ail gene was not detected in all of 23 strains that determined non-pathogenic. In antimicrobial susceptibility test, twelve strains (52.2%) of 23 isolates showed the multi -resistant patterns with over 3 drugs. PFGE was performed after the genomic DNA of twenty three isolates, which was digested with Xba I. the 23 isolates showed 12 ($A{\sim}L$) PFGE type.

• Journal of Microbiology and Biotechnology
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• v.29 no.8
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• pp.1316-1323
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• 2019

Middle East respiratory syndrome coronavirus (MERS-CoV) is a newly emerging coronavirus which is zoonotic from bats and camels. Its infection in humans can be fatal especially in patients with preexisting conditions due to smoking and chronic obstructive pulmonary disease (COPD). Among the 25 proteins encoded by MERS-CoV, 5 accessory proteins seem to be involved in viral evasion of the host immune responses. Here we report that ORF4a, ORF4b, and ORF8b proteins, alone or in combination, effectively antagonize nuclear factor kappa B ($NF-{\kappa}B$) activation. Interestingly, the inhibition of $NF-{\kappa}B$ by MERS-CoV accessory proteins was mostly at the level of pattern recognition receptors: melanoma differentiation-associated gene 5 (MDA5). ORF4a and ORF4b additively inhibit MDA5-mediated activation of $NF-{\kappa}B$ while that of retinoic acid-inducible gene 1 (RIG-I) is largely not perturbed. Of note, ORF8b was found to be a novel antagonist of MDA5-mediated $NF-{\kappa}B$ activation. In addition, ORF8b also strongly inhibits Tank-binding kinase 1 (TBK1)-mediated induction of $NF-{\kappa}B$ signaling. Taken together, MERS-CoV accessory proteins are involved in viral escape of $NF-{\kappa}B$-mediated antiviral immune responses.

• Parasites, Hosts and Diseases
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• v.57 no.2
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• pp.207-211
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• 2019

Anisakiasis is a zoonotic disease induced by anisakid nematodes, and endoscopic inspection is used for a diagnosis or remedy for it. Anisakis simplex, Anisakis physeteris, and Pseudoterranova decipiens had been reported to be the major species causing human infections, particularly, in Japan. However, in Korea, recent studies strongly suggested that Anisakis pegreffii is the major species of human infections. To support this suggestion, we collected anisakid larvae (n=20) from 20 human patients who were undergone gastrointestinal endoscopy at a health check-up center in Korea, and molecular identification was performed on the larvae using PCR-RFLP analysis and gene sequencing of rDNA ITS regions and mtDNA cox2. In addition, anisakid larvae (n=53) collected from the sea eel (Astroconger myriaster) were also examined for comparison with those extracted from humans. The results showed that all human samples (100%) were identified as A. pegreffii, whereas 90.7% of the samples from the sea eel were A. pegreffii with the remaining 9.3% being Hysterothylacium aduncum. Our study confirmed that A. pegreffii is the predominant species causing human anisakiasis in Korea, and this seems to be due to the predominance of this larval type in the fish (sea eels) popularly consumed by the Korean people. The possibility of human infection with H. aduncum in Korea is also suggested.

• Korean Circulation Journal
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• v.53 no.6
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• pp.351-366
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• 2023

Along with the development of immunosuppressive drugs, major advances on xenotransplantation were achieved by understanding the immunobiology of xenograft rejection. Most importantly, three predominant carbohydrate antigens on porcine endothelial cells were key elements provoking hyperacute rejection: α1,3-galactose, SDa blood group antigen, and N-glycolylneuraminic acid. Preformed antibodies binding to the porcine major xenoantigen causes complement activation and endothelial cell activation, leading to xenograft injury and intravascular thrombosis. Recent advances in genetic engineering enabled knock-outs of these major xenoantigens, thus producing xenografts with less hyperacute rejection rates. Another milestone in the history of xenotransplantation was the development of co-stimulation blockaded strategy. Unlike allotransplantation, xenotransplantation requires blockade of CD40-CD40L pathway to prevent T-cell dependent B-cell activation and antibody production. In 2010s, advanced genetic engineering of xenograft by inducing the expression of multiple human transgenes became available. So-called 'multi-gene' xenografts expressing human transgenes such as thrombomodulin and endothelial protein C receptor were introduced, which resulted in the reduction of thrombotic events and improvement of xenograft survival. Still, there are many limitations to clinical translation of cardiac xenotransplantation. Along with technical challenges, zoonotic infection and physiological discordances are major obstacles. Social barriers including healthcare costs also need to be addressed. Although there are several remaining obstacles to overcome, xenotransplantation would surely become the novel option for millions of patients with end-stage heart failure who have limited options to traditional therapeutics.