• Parasites, Hosts and Diseases
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• v.26 no.1
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• pp.55-60
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• 1988

A human case of Centrocestus armatus (Heterophyidae) infection was proved by identifying an adult worm collected after treatment with praziquantel in Korea. The case is 42-year old man who resides in a rural area in Sanchung-gun, Kyeongsangnam·do. The case was concomitantly infected with Clonorchis sinensis and had the history of eating raw (reshwater fishes including Zacco platypus, which are known to be the second intermediate host of C. armatus in Korea. This is the first report of natural human infection by C. armatus in the literature.

• Parasites, Hosts and Diseases
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• v.37 no.1
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• pp.55-57
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• 1999

During the period from October 1996 to November 1998, the infection status of Paragonimus westermani metacercariae in freshwater crayfish (Cambaroides similis) collected from Bogildo (islet), Wando-gun, Chollanam-do, which is known for an endemic area of P. westermani in Korea, were examined. The average infection rate of Paragonimus metacercariae in crayfish was 88.6%, and mean number of metacercariae per infected crayfish was 30.2. This metacercarial density was the highest in the group of weight in 7.1-9.0 g. These results suggest that the natural life cycle of P. westermani is still well-preserved in Bogildo.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.33 no.3
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• pp.183-187
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• 2022

Dysphonia is well known as one of the otolaryngological symptoms of coronavirus disease 2019 (COVID-19) infection. The vocal changes of the COVID-19 condition have been reported in terms of parameters of multi-dimensional voice assessment, including acoustic analysis, auditory-perceptual evaluation, and psychometric assessment. However, there has not been a daily followup study in patients with acute COVID-19 infection. In this study, a 41-year-old male performed daily voice recordings of vowel phonation and passage-reading tasks during the self-quarantine period of one week. Compared to the normal voice status of the prepandemic period, voice abnormalities peaked on day two after the diagnosis of COVID-19 infection and recovered after one week.

• Applied Microscopy
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• v.45 no.2
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• pp.80-88
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• 2015

The structural change and distribution of mitochondrial enzyme (ATPase, cytochrome-c-oxidase), cell proliferation (proliferating cell nuclear antigen, PCNA), cell death (caspase-3) and cell growth factor (fibroblast growth factor 8, FGF-8) in the Sprague-Dawley rat bile duct during Clonorchis sinensis infection was investigated. Experimental groups were divided into C. sinensis infection, superinfection and reinfection of C. sinensis after 'praziquantel' treatment group. As a result, C. sinensis infected rat bile ducts showed the features of chronic clonorchiasis, i.e., connective tissue thickening, ductal fibrosis and epithelial tissue dilatation. PCNA for cell proliferation increased in the infection group, and decreased after praziquantel treatment. Caspase-3 was distributed in reinfection group only. FGF-8 was distributed in the rat bile duct after praziquantel treatment but not distributed in infection and reinfection group. Overall, C. sinensis infection causes physical and chemical irritations and then brings on the abnormalities of intracellular energy metabolism and cellular growth factors, which hinders bile duct tissue from functioning properly, and resultingly, fibrosis occurs and epithelial cells dilated abnormally. More intense infection makes tissue fibrosis chronical and activates apoptosis factors.

• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.505-510
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• 2001

A total of 701 swine sera from 55 swine farms (Mar, 1998 through Feb, 2001) were nation-widely collected for the presence of antibody to porcine parvovirus (PPV) in sows and 30-, 60-, 90-day-old pigs. Sero-prevalence by haemagglutination inhibition assay with guinea pig red blood cells was investigated on the basis of year, region and season, respectively. In general, there was no significant difference with gradual decrease of passive immunity for the sero-prevalence to PPV in sows and 30-, 60-, 90-day-old pigs for the period of 1999 and 2000. However, regional variation was observed in the provinces of Kyonggi, Choongnam and Kyungnam, Natural infection of the virus in 90-day-old pigs was increased during the fall and the winter. Thus, it seems that the natural infection of PPV in growing pigs may be attributed to the increased outbreak of postweaning multisystemic wasting syndorme in co-infection with porcine circoviruses.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.990-996
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• 2008

In a previous study, we found an antifungal effect on human pathogenic fungi by the cell-penetrating peptide Tat (47-58) derived from HIV-1. Tat (47-58) immediately entered into the fungal nucleus and affected some physiological changes on the intracellular condition. In this study, Tat (47-58) showed a broad spectrum of antibacterial activity against pathogenic bacteria including bacterial clinical isolates. To improve resistance against proteases for use in vivo, we synthesized an analog of Tat (47-58) by substituting the L-amino acid for the D-amino acid. The D-enantiomer of Tat (47-58) also exhibited a broad spectrum of antibacterial activity at almost the same level of L-Tat (47-58) concentration. Unlike L-Tat (47-58), D-Tat (47-58) showed a significant proteolytic resistance against all proteases tested and antimicrobial activities in the presence of trypsin. Moreover, D-Tat (47-58) inhibited MRSA infection in human HeLa cells whereas L-Tat (47-58) partially allowed MRSA infection, and the results were due to the proteolytic resistance of D-Tat (47-58).

• Parasites, Hosts and Diseases
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• v.54 no.5
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• pp.591-603
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• 2016

Investigations of Enterobius sp. infection in prehistory have produced a body of data that can be used to evaluate the geographic distribution of infection through time in the Americas. Regional variations in prevalence are evident. In North America, 119 pinworm positive samples were found in 1,112 samples from 28 sites with a prevalence of 10.7%. Almost all of the positive samples came from agricultural sites. From Brazil, 0 pinworm positive samples were found in 325 samples from 7 sites. For the Andes region, 22 pinworm positive samples were found in 411 samples from 26 sites for a prevalence of 5.3%. Detailed analyses of these data defined several trends. First, preagricultural sites less frequently show evidence of infection compared to agricultural populations. This is especially clear in the data from North America, but is also evident in the data from South America. Second, there is an apparent relationship between the commonality of pinworms in coprolites and the manner of constructing villages. These analyses show that ancient parasitism has substantial value in documenting the range of human behaviors that influence parasitic infections.

• Tuberculosis and Respiratory Diseases
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• v.82 no.2
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• pp.94-101
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• 2019

Nontuberculous mycobacteria (NTM) are ubiquitous organisms that are generally found not only in the natural environment but also in the human engineered environment, including water, soil, and dust. These organisms can form biofilms and can be readily aerosolized because they are hydrophobic owing to the presence of the lipid-rich outer membrane. Aerosolization and subsequent inhalation were the major route of NTM lung disease. Water distribution systems and household plumbing are ideal habit for NTM and the main transmission route from natural water to household. NTM have been isolated from drinking water, faucets, pipelines, and water tanks. Studies that used genotyping have shown that NTM isolates from patients are identical to those in the environment, that is, from shower water, showerheads, tap water, and gardening soil. Humans are likely to be exposed to NTM in their homes through simple and daily activities, such as drinking, showering, or gardening. In addition to environmental factors, host factors play an important role in the development of NTM lung disease. The incidence and prevalence of NTM lung disease are increasing worldwide, and this disease is rapidly becoming a major public health problem. NTM lung disease is associated with substantially impaired quality of life, increased morbidity and mortality, and high medical costs. A more comprehensive understanding of the infection source and epidemiology of NTM is essential for the development of new strategies that can prevent and control NTM infection.

• Parasites, Hosts and Diseases
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• v.27 no.1
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• pp.23-34
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• 1989

In an attempt to investigate the effect of Hymenolepis dana infection on immunological responses to sRBC in ICR strain of mice, cellular and humoral immune responses were chronologically monitored after sensitization with sRBC. Mice weighing about 20 g were allocated into artificial and natural infection groups. The shell-free eggs of H. dana were inoculated into mice on the day 0 (initial) and day 10 in the former group, and praziquantel (25 mg/kg/day) was administered for 3 days to the one half of the mice at the 15th day after the first inoculation and to all of the mice in natural infection group. In artificial infection group, the delayed-type hypersensitivity (DTH) to sRBC was considerably decreased on the day 10 after the first inoculation, and then elevated gradually to normal. Eosinophils in the peripheral blood increased slightly. The hemagglutinin (HA) and hemolysin (HE) titers during the early stage were shown to be more or less higher than those of control. Thereafter, the titers were returned to normal, followed by a transient decrease on the day 15 post-infection. The sRBC rosette and antibody-treated rosette-forming capacities on the day 15 post.infection were temporarily lowered but became higher thereafter. The mucosal mast cells (MMC) in the small intestine were gradually increased to make a peak on the day 10 post-infection and then maintained more or less at lower level. After praziquantel treatment, the DTH and the number of eosinophils were decreased slightly and the MMC number and sRBC rosette-forming capacity were considerably decreased. The titers of HA and HE and antibody-treated rosette-forming capacity, however, were elevated in general. In natural infection group, the DTH, the number of eosinophils, and MMC which were elevated due to H. dana infection were gradually returned to normal after prasiquantel treatment. The titers of HA and HE which were decreased by parasite infection were increased to normal after the treatment. However, the capacities of sRBC rosette or antibody-treated rosette formation were maintained at low levels in spite of the treatment. These results revealed that the immune responses to sRBC were significantly activated during H. dana infection, although they were transiently decreased during the days 10~15 post-infection.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2003.10a
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• pp.101-101
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• 2003