• Journal of Medicine and Life Science
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• 제20권1호
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• pp.43-47
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• 2023

Streptococcus suis (S. suis) is an emerging zoonotic pathogen that causes bacterial meningitis in humans. S. suis is an encapsulated gram-positive facultative anaerobic bacterium and is an important pathogen in pigs. This infectious disease usually manifests in humans as meningitis, endocarditis, septicemia, and arthritis. Most cases originate in Southeast Asia, and human S. suis infections are often reported in countries with a high density of pigs. Meningitis is a common clinical manifestation of S. suis infection. Moreover, hearing loss is a common complication that can be bilateral, profound, and/or permanent. This report presents two cases of bacterial meningitis and hearing loss caused by S. suis in patients without a history of direct exposure to pigs in an intensive pork industry region.

• Applied Microscopy
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• 제52권
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• pp.11.1-11.9
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• 2022

Zoonotic poxvirus infections pose significant threat to human health as we have witnessed recent spread of monkeypox. Therefore, insights into molecular mechanism behind poxvirus replication cycle are needed for the development of efficient antiviral strategies. Virion assembly is one of the key steps that determine the fate of replicating poxviruses. However, in-depth understanding of poxvirus assembly is challenging due to the complex nature of multi-step morphogenesis and heterogeneous virion structures. Despite these challenges, decades of research have revealed virion morphologies at various maturation stages, critical protein components and interactions with host cell compartments. Transmission electron microscopy has been employed as an indispensable tool for the examination of virion morphology, and more recently for the structure determination of protein complexes. In this review, we describe some of the major findings in poxvirus morphogenesis and the contributions of continuously advancing electron microscopy techniques.

• Parasites, Hosts and Diseases
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• 제55권3호
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• pp.351-355
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• 2017

Hymenolepis nana and Hymenolepis diminuta are globally widespread zoonotic cestodes. Rodents are the main reservoir host of these cestodes. Brown rats (Rattus norvegicus) are the best known and most common rats, and usually live wherever humans live, especially in less than desirable hygiene conditions. Due to the little information of the 2 hymenolepidid species in brown rats in China, the aim of this study was to understand the prevalence and genetic characterization of H. nana and H. diminuta in brown rats in Heilongjiang Province, China. Total 114 fecal samples were collected from brown rats in Heilongjiang Province. All the samples were subjected to morphological examinations by microscopy and genetic analysis by PCR amplification of the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene and the internal transcribed spacer 2 (ITS2) region of the nuclear ribosomal RNA gene. In total, 6.1% (7/114) and 14.9% (17/114) of samples were positive for H. nana and H. diminuta, respectively. Among them, 7 and 3 H. nana isolates were successfully amplified and sequenced at the COX1 and ITS2 loci, respectively. No nucleotide variations were found among H. nana isolates at either of the 2 loci. Seventeen H. diminuta isolates produced 2 different COX1 sequences while 7 ITS2 sequences obtained were identical to each other. The present results of H. nana and H. diminuta infections in brown rats implied the risk of zoonotic transmission of hymenolepiasis in China. These molecular data will be helpful to deeply study intra-specific variations within Hymenolepis cestodes in the future.

• 대한수의학회지
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• 제56권4호
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• pp.249-254
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• 2016

As the meat of black goats has become popular as a healthy food, domestic goat meat-related industries are steadily growing. However, previous studies are scarce of informations about the zoonotic disease originated from the black goat in Korea. In this study, we investigated Korean black goat's infectious diseases representing bovine tuberculosis, brucellosis, and Q fever. One hundred and eighty samples were collected from a local slaughter house located in Jeollanam-do. Three typical zoonotic diseases were separately examined by carrying out enzyme linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). Histopathological test was additionally performed in tuberculosis. In case of tuberculosis, results of the PCR and histopathological test were negative but the ELISA results were positive in eight samples. In case of brucellosis, one out of the total samples was shown to be positive in the ELISA and none in the PCR. In case of Q fever, there were forty one positive in the ELISA and twenty positive in the real-time PCR. Those results indicate that the Korean black goat could be a natural reservoir in the possible chain-infections among human, cows and goats. Thus, further study needs in order to improve productivity as well as to prevent the zoonosis spreading and circulation of other livestock with the black goat in this country.

• Journal of Veterinary Science
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• 제23권2호
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• pp.20.1-20.8
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• 2022

Background: Emergent and re-emergent canine tick-borne infections are attracting increasing attention worldwide. The rise in pet ownership and the close relationship between dogs and their owners are the most concerning factors because dogs may act as competent reservoirs for human tick-transmitted infectious agents. Objectives: This study contributes to the epidemiological surveillance of canine tick-transmitted infections with zoonotic risk in the Republic of Korea (ROK) by investigating the seroprevalence of the pathogens, Anaplasma spp., Borrelia burgdorferi, and Ehrlichia canis. Methods: Four hundred and thirty whole blood samples from domestic dogs were collected in seven metropolitan cities and nine provinces in the ROK and tested using SensPERT Ab test kits (VetAll Laboratories^®) to detect seroreactive animals. Results: The seroprevalence rates identified were 9.8% (42/430) for Anaplasma spp., 2.8% (12/430) for B. burgdorferi, and 1.4% (6/430) for E. canis. The risk factors evaluated in this study that could be associated with the development of a humoral immune response, such as sex, age, and history of tick exposure, were similar. There was only one exception for dogs seroreactive to Anaplasma spp., where the risk factor "tick exposure" was statistically significant (p = 0.047). Conclusions: This serological survey exhibited the widespread presence of Anaplasma spp., B. burgdorferi, and E. canis throughout the ROK. Hence, dogs may play a key role as the sentinel animals of multiple zoonotic infectious agents in the country.

• Parasites, Hosts and Diseases
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• 제57권2호
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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.

• Journal of Korean Neurosurgical Society
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• 제55권1호
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• pp.48-50
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• 2014

Brucellosis is caused by gram-negative, aerobic, non-motile, facultative, intracellular coccobacilli belonging to the genus Brucella. A 50-year-old man working as an employee was admitted to neurosurgery clinic with severe low back, radicular right leg pain and hypoesthesia in right L4-5 dermatomes for 2 months. Brucella tube agglutination (Wright) test was positive in serum sample of the patient with a titer of 1/640. Brucella melitensis was isolated from blood culture. X-ray and MRI of the lomber spine showed massive collapse of L4 vertebral body. Neural tissue was decompressed and then posterior L3-5 short segment transpedicular screw fixation and stabilization was performed. Brucella melitensis was isolated from microbiologic culture of pathologic specimen. Antibiotic therapy was given as doxycycline 200 mg/day and rifampicin 600 mg/day for 6 months. Brucellosis is a systemic zoonotic infection and still an important public health problem in many geographical parts of the world. Vertebral body collapse caused by brucellosis occurs very rarely but represents a neurosurgical emergency because of its potential for causing rapidly progressive spinal cord compression and permanent paralysis. Neurosurgeons, emergency department personnel as well as infectious disease specialists should always keep a high index of suspicion and include brucellosis in the differential diagnosis of vertebral body collapse.

• Parasites, Hosts and Diseases
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• 제52권3호
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• pp.299-304
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• 2014

This study aimed to identify the assemblages (or subassemblages) of Giardia duodenalis by using normal or nested PCR based on 4 genetic loci: glutamate dehydrogenase (gdh), triose phosphate isomerase (tpi), ${\beta}$-giardin (bg), and small subunit ribosomal DNA (18S rRNA) genes. For this work, a total of 216 dogs' fecal samples were collected in Guangdong, China. The phylogenetic trees were constructed with MEGA5.2 by using the neighbor-joining method. Results showed that 9.7% (21/216) samples were found to be positive; moreover, 10 samples were single infection (7 isolates assemblage A, 2 isolates assemblage C, and 1 isolate assemblage D) and 11 samples were mixed infections where assemblage A was predominant, which was potentially zoonotic. These findings showed that most of the dogs in Guangdong were infected or mixed-infected with assemblage A, and multi-locus sequence typing could be the best selection for the genotype analysis of dog-derived Giardia isolates.

• Parasites, Hosts and Diseases
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• 제56권3호
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• pp.215-227
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• 2018

Along with globalization of traveling and trading, fish-borne nematodiases seems to be increasing in number. However, apart from occasional and sporadic case reports or mini-reviews of particular diseases in particular countries, an overview of fish-borne nematodiasis among travelers have never been performed. In this review, we gathered fish-borne nematodiasis among travelers for recent 25 years by an extensive global literature survey using appropriate keywords, e.g. travelers diseases, human infection, anisakiasis, gnathostomiasis, capillariasis, sushi, sashimi, ceviche, Gnathostoma, Pseudoterranova, Anisakis, Capillaria, etc., as well as various combinations of these key words. The Internet search engines PubMed, Medline, Google and Googler Scholar were used as much as possible, and the references of every paper were checked in order to identify useful and reliable publications. The results showed unexpectedly high incidence of gnathostomiasis and low incidence of anisakidosis. The different incidence values of the infection with several fish-borne zoonotic nematode species are discussed, as well as some epidemiological aspects of the infections. The difficulties of differential diagnosis in non-endemic countries are emphasized. It is concluded that travelers must avoid risky behaviors which can lead to infection and that physicians and health authorities must advice travelers on the risks of eating behaviors during travel.

• 한국미생물·생명공학회지
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• 제48권4호
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• pp.569-573
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• 2020

Brucellosis is a zoonotic disease caused by Brucella infections and humans usually contract this disease from close contact with infected animals or their products, usually via the ingestion of cheese or crude milk. Macrophage migration inhibitory factor (MIF) and Pro- and anti-inflammatory cytokines play an important role in susceptibility/resistance and the immunopathogenesis of Brucella infection. These cytokines are crucial factors in the initiation and progression of protective immunity against Brucella infection but the role of MIF has not been well studied in the human response to intracellular microbes. This study was designed to investigate the effect of MIF expression on Brucella susceptibility. A total of 85 positive rose Bengal tests and 24 samples from healthy individuals were collected for this study and subjected to polymerase chain reaction assays (PCR) of the bcsp31 diagnostic gene. MIF concentrations were evaluated using Enzyme-Linked immunosorbent assay (ELISA) and the results showed that 46 (54%) of the rose Bengal test samples were positive and 39 (46%) were negative for bcsp31 (p ≤ 0.05) and used as the gold standard for all of the comparisons in this study. The ELISA results indicate that the mean concentration of MIF was significantly higher in patients with positive rose Bengal tests when compared to the control groups and that its concentration increases with increasing age in both the patient and control groups (p ≤ 0.05).