• Korean Journal of Radiology
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• v.21 no.4
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• pp.505-508
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• 2020

The epidemic of 2019 novel coronavirus, later named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is still gradually spreading worldwide. The nucleic acid test or genetic sequencing serves as the gold standard method for confirmation of infection, yet several recent studies have reported false-negative results of real-time reverse-transcriptase polymerase chain reaction (rRT-PCR). Here, we report two representative false-negative cases and discuss the supplementary role of clinical data with rRT-PCR, including laboratory examination results and computed tomography features. Coinfection with SARS-COV-2 and other viruses has been discussed as well.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5439-5444
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• 2012

Objective: To explore the correlation of human papillomavious (HPV) infection with expression of p53 and proliferating cell nuclear antigen (PCNA) in patients with different ethnicity in Xinjiang, China. Methods: 166 biopsy specimens from 83 laryngeal squamous cell carcinomas (LSCC), 63 laryngeal papillomas (LP), and 20 laryngeal inflammatory polyps (LIP) were included in this study. HPV infection was determined by polymerase chain reaction (PCR) using specific types of HPV primers. Expression of p53 and PCNA was assessed using immunohistostaining. Results: The frequency of HPV 6/11 was higher in LP (33.3%) than in LSCC (9.6%) (P<0.0005), whereas the frequency of HPV 16/18 was higher in LSCC (37.3 %) than in LP (6.3%) (P<0.0005). Patients of the Han ethnic group with LSCC had a higher infection rate with HPV 6/11 or HPV 6/11 and HPV 16/18 coinfection than those of Uygur and Kazak ethnicity (P<0.05). Overexpression of p53 and PCNA were higher in LSCC (62.7%, 57.8%) than in LP (38%, 33.3%) (P<0.005, and P<0.005, respectively). That of p53 was not associated with lymph-node metastases and clinical stages, but overexpression of PCNA closely correlated with clinical stage. Conclusions: These results strongly implicate HPV6/11 infection in the carcinogenesis of LSCC and LP, respectively. There was a higher coincidence of increased malignancy of laryngeal tumors with overexpression of p53 and PCNA. Overexpression of p53 may serve as an early risk marker for malignant transformation in HPV infected cells while the overexpression of PCNA may serve as a late marker for progression of LSCC.

• Korean Journal of Veterinary Research
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• v.57 no.2
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• pp.143-146
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• 2017

Porcine ear necrosis syndrome is characterized by erosive and ulcerative lesions at the margin or tip of the pinna. Three growing pigs of different ages exhibited retarded growth accompanied by reddening and necrosis of ear prior to death. Gross examination showed reddening, swelling, black discoloration, scaling, and variable-sized yellowish materials and edema in ear cross section. Microscopically, thrombosis, abscess, ulceration, epidermal hyperplasia, and dermal pyogranulomatous inflammation with an intralesional bacterial colony were observed. Staphylococcus hyicus was isolated in all pigs' ears and porcine reproductive and respiratory syndrome virus was detected by PCR and immunohistochemistry.

• Journal of Sericultural and Entomological Science
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• v.38 no.1
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• pp.36-41
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• 1996

Recombinant baculoviruses having expanded host range were selected by coinfection of Autographa california NPV and Bombyx mori NPV into Sf-9 and BmN-4 insect cell lines. In order to determine the polyhedra morhplogy of RecS-A6, one of a recombinant baculovirus, polyhedra of RecS-A6 produced in insect cells were observed by phase contrast microscope and scanning electron microscope. The results revealed that the recombinant baculovirus had a various polyhedra morphology which was different from its parental viruses, suggesting that the various morhpology of recombinant baculovirus with an expanded host range was due to the genetic recombination of viral genome. To analyze the genomic recombinantion of the recombinant baculoviruses, genomic DNAs of two parent viruses and RecS-A6 were digested with restriction endonuclease and subjected to agarose gel electrophoresis. Southern blot analysis revealed that RecS-A6 has two polyhedrin gene of AcNPV and BmNPV in a viral genome. Polyhedral protein of recombinant baculovirus was analysed by SDS-PAGE. The result showed that molecular weight of polyhedral protein of RecS-A6 containing two polyhedrin gene of AcNPV and BmNPV was as the 31 kDa band of AcNPV and 30 kDa band of BmNPV.

• Research in Plant Disease
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• v.19 no.3
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• pp.233-236
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• 2013

This research was conducted to investigate the incidence of viral infection in Samcheok-shi and Jeongseon-gun, main garlic growing areas of Gangwon province in Korea. Four primers sets (GLV, LYSV, GCLV, OYDV) were used for RT-PCR to test of 100 samples collected from each location. Infection rates of GLV, LYSV, GCLV and OYDV of garlic samples from Samcheok-shi and Jeongseon-gun were 95, 95, 92 and 33%, respectively. All garlic samples tested in this research were infected at least one virus. Coinfection of 3 kinds of virus (GLV, LYSV and GCLV) and 4 kinds of virus (GLV, LYSV, GCLV and OYDV) were 60 and 25%, respectively. While infections of GLV, LYSV and GCLV were evenly found in both two regions, OYDV infection of garlic samples collected from Jeongseon-gun was higher than Samcheok-shi. Viral infections at garlic fields of whole country and Gangwon province are very serious now. Therefore, it is very necessary to develop technic for virus-free bulb and renew seed bulb of garlic.

• The Plant Pathology Journal
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• v.31 no.1
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• pp.90-96
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• 2015

Garlic generally becomes coinfected with several types of viruses belonging to the Potyvirus, Carlavirus, and Allexivirus genera. These viruses produce characteristically similar symptoms, they cannot be easily identified by electron microscopy (EM) or immunological detection methods, and they are currently widespread around the world, thereby affecting crop yields and crop quality adversely. For the early and reliable detection of garlic viruses, virus-specific sets of primers, including species-specific and genus-specific primers were designed. To effectively detect the twelve different types of garlic viruses, primer mixtures were tested and divided into two independent sets for multiplex polymerase chain reaction (PCR). The multiplex PCR assays were able to detect specific targets up to the similar dilution series with monoplex reverse transcription (RT)-PCR. Seventy-two field samples collected by the Gyeongbuk Agricultural Technology Administration were analyzed by multiplex RT-PCR. All seventy two samples were infected with at least one virus, and the coinfection rate was 78%. We conclude that the simultaneous detection system developed in this study can effectively detect and differentiate mixed viral infections in garlic.

• Parasites, Hosts and Diseases
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• v.56 no.3
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• pp.281-285
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• 2018

Cryptosporidium is the most common protozoan that can infect a wide range of animals, including mammals and birds. Avian Cryptosporidium spp. can cause enteric and respiratory diseases which can be fatal in birds and some species are zoonotic. Companion birds have the potential as reservoir due to their close contact with humans. Pet shops are the major source of companion birds. However, few reports are available regarding Cryptosporidium spp. infection among companion birds kept in pet shops. The present study reports the prevalence and molecular characteristics of Cryptosporidium spp. among companion birds kept in pet shops in Japan. A total of 265 fresh fecal samples were obtained from birds kept in 4 pet shops; these birds belonged to 41 species in 3 bird orders. A nested polymerase chain reaction (PCR) assay targeting the small subunit rRNA gene was employed for the detection of Cryptosporidium spp. A total of 24 samples (9.1%) were positive, and Cryptosporidium spp. were detected from all pet shops. The prevalence of Cryptosporidium spp. in each of the bird orders was 6.5% (10/153) in Psittaciformes, 14.4% (13/90) in Passeriformes, and 4.5% (1/22) in Galliformes. Based on sequence analysis, 13 (54.2%) isolates were classified to C. galli, 8 (33.3%) were avian genotype III, and the remaining 3 (12.5%) were C. baileyi. No infection with zoonotic C. meleagridis and no coinfection with multiple Cryptosporidium spp. and/or genotypes were observed. The zoonotic potential of Cryptosporidium spp. infecting companion birds kept in pet shops in Japan is likely to be low.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 1997.06a
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• pp.73-101
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• 1997

Baculoviruses are characterized by large double-stranded circular DNA genomes and rod-shaped enveloped virions. Bombyx mori nucleopolyhedrovirus(BmNPV) is a major pathogen, which causes severe damage in sericulture. Currently, BmNPV is recogtnized as an improtant tool in molecular biology, especially for expression of useful genes in B.mori cells and silkworm larvae. Our laboratories have focused on the studies of the molecular mechanisms of BmNPV replication and the application of BmNPV to agriculture and medicine. The entire nucleotide sequence of the BmNPV genome has recently determined. The BmNPV genome possessed 135 putative genes and 7 homologous repeated sequence (hrs) regions. Relatively little space, a few to a few hundred base-pairs, was observed between the open reading frames and hrs. Termination codons often overlapped. These results showed a compactly packde BmNPV genome. Based on comparative sequence analyses, we speculated that the ancestor of BmNPV was a baculovirus similar to Autographa californica NPV(AcNPV). The function of the BmNPV genes were characterized by gene deletion analysis; p35 was found to be involved in blocking apoptosis and cysteine proteinase was found to be involved in horizontal virus transmission by degrading viral-infected larval host. By AcNPV and BmNPV coinfection experiments, we identified a BmNPV gene involved in expanding host specificity of AcNPV. The identified gene was likely encoded a DNA helicase based on the amino acid sequence analysis; a few amino acid substitutions in the putative DNA helicase gene resulted in the expansion of host range of AcNPV. These findings indicate that BmNPV evolved within a short period from an AcNPV-like ancestral virus due to rapid evolution including specific amino acid substitutions and gene deletions/insertions.

• Fisheries and Aquatic Sciences
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• v.26 no.7
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• pp.437-446
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• 2023

Cyprinids are popular species for aquaculture worldwide, with Asia being a significant contributor to their production. In Korea, common carp (Cyprinus carpio), koi carp (Cyprinus rubrofuscus), and goldfish (Carassius auratus) are cultivated domestically and imported for ornamental or human consumption purposes. Among the viruses that infect cyprinids, cyprinid herpesvirus-2 (CyHV-2), koi herpesvirus (KHV, also known as cyprinid herpesvirus-3), and carp edema virus (CEV) are of particular concern as they cause substantial economic losses to the aquaculture industry. In this study, we investigated these viruses in both of domestic and imported cyprinids. Our results revealed that CyHV-2 was only detected in imported goldfish from Thailand. To further investigate the genetic characteristics of them, the marker A region was analyzed. Despite belonging to the same cluster with isolates from China, France, Poland, and Israel, CyHV-2 detected in this study showed distinct differences in their repetitive sequence sizes. Furthermore, two different forms of KHV/CEV coinfection were identified from domestic koi carp, both of which exhibited typical symptoms. Phylogenetic analysis showed that one KHV isolate (ScKc-2105-K) was of the Asian type and closely related to isolates from Japan, Indonesia, Belgium, Taiwan, and China. Two CEV isolates (ScKc-2105-CE and GhKc-2207-CE) be- longed to the IIa type and showed high similarity with isolates from the USA, France, and Korea. Notably, koi carp injected with cultured KHV (ScKc-2105-K) showed 78.0% cumulative mortality within 14 days post-injection (dpi). Our findings support the importance of regular surveillance of viral diseases in cyprinids.

• Clinical and Experimental Pediatrics
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• v.51 no.7
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• pp.729-735
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• 2008

Purpose : Chlamydia trachomatis is one of the most common sexually transmitted diseases and is also a cause of pneumonia in infants. Respiratory infections by respiratory viruses are also common for infants. The objectives of this study were to identify the clinical manifestations and to determine the prevalence of C. trachomatis respiratory infections and coinfections by respiratory viruses in infants younger than 6 months of age. Methods : For this study, we enrolled 6 months or younger infants who were admitted to the Dankook University Hospital between January 2002 and July 2007, with respiratory symptoms. Nasopharyngeal aspirates or throat swabs were collected within s d of hospitalization and C. trachomatis was detected using polymerase chain reaction (PCR). Patients who tested positive underwent multiplex PCR for respiratory viruses. Results : A total of 690 patients underwent chlamydial PCR testing and 36 (5.2%) had positive results. Of the 36, 28 (78%) were male; 30 were vaginally delivered. From the 36 patients positive for C. trachomatis, 26 underwent multiplex respiratory viral PCR; 12 were coinfected with viruses. Respiratory syncytial virus (RSV) was the most frequent pathogen that was detected in 6 patients. Increased C-reactive protein and fever were significant in patients coinfected with respiratory viruses. Conclusion : C. trachomatis can infected in infants delivered by cesarean section as well as in 6 months old or younger infants. Infant with C. trachomatis respiratory infections can also be coinfected with respiratory infection also coinfected with respiratory viruses. Further studies are needed to better understand the prevalence rates of the this infection and its coinfection rate with respiratory viruses.