• Parasites, Hosts and Diseases
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• v.31 no.4
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• pp.347-352
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• 1993

Six early third-stage larvae of Gnnthostoma nipponicum were recovered from the muscle of 376 loaches, Misgurnw anguiILicnudatus, imported from China. They were 614 × 114㎛ in average size, almost colorless except brownish intestine, and encircled by about 229 transverse rows of minute cuticular spines. Their head bulbs provided with 3 rows of hooklets, of which average number were 34.5 on the first, 36.7 on the second and 39.7 on the third. According1y, it is revealed that the Chinese loach is a natural second intermediate host of G. nipponicum and G. nipponicum has been distributed somewhere in China. This parasite may infect human when the imported loaches are consumed raw.

• Parasites, Hosts and Diseases
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• v.45 no.2 s.142
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• pp.115-120
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• 2007

Parvatrema chaii n. sp. (Digenea: Gymnophallidae) is described using the worms recovered from experimentally infected mice in Korea. The metacercariae were collected from surf-clams, Mactra veneriformis, from a tidal flat in Sochon-gun, Chungchongnam-do. The metacercariae were elliptical ($0.262{\times}0.132 mm$), and the genital pore had an anterior arch of 16-17 sensory papillae in scanning electron microscopic view, Adult worms were ovoid to foliate (0.275-0.303 by 0.140-0.150 mm), and their characteristic features included the presence of lateral lips, short esophagus, genital pore located some distance anterior to the ventral sucker, club-shaped seminal vesicle, a compact to slightly lobed vitellarium, elliptical eggs (0.018-0.020 by 0.010-0.013 mm), and absence of the ventral pit. This gymnophallid is classified as a member of the genus Parvatrema because of the location of the wide genital pore some distance from the ventral sucker, and the absence of the ventral pit. It differs from previously reported Parvatrema species, including the type species, P. borinquenae. In particular, the morphologies of the vitellarium and the genital pore with an anterior arch of 16-17 sensory papillae are unique features. Therefore, we propose it as a new species, Parvatrema chaii n. sp. (Digenea: Gymnophallidae).

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.761-767
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• 2018

Degenerative diseases are commonly associated with excess free radicals. Acer okamotoanum, a plant endemic to Korea, is reported to have anti-oxidant, anti-cancer, and anti-viral activities. We previously isolated flavonoids from the ethyl acetate fraction of A. okamotoanum such as quercitrin (QU), isoquercitrin (IQ), and afzelin (AF). In the present study, the in vitro antioxidant activity of flavonoids such as QU, IQ, and AF isolated from the ethyl acetate fraction of A. okamotoanum were investigated by measuring the free radical scavenging activity including 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical ($^{\cdot}OH$), and superoxide anion ($O_2{^-}$). The flavonoids (QU, IQ, and AF) concentration-dependently showed a DPPH radical scavenging activity. In particular, QU and IQ showed a higher DPPH radical scavenging activity than that of AF. In addition, the flavonoids (QU, IQ, and AF) at $10{\mu}g/mL$ showed over an 80% scavenging effect against $^{\cdot}OH$ radical production. Furthermore, the $O_2{^-}$ radical scavenging activity of the flavonoids, QU, IQ, and AF increased in a dose-dependent manner. Particularly, IQ exerted the strongest scavenging activities against $^{\cdot}OH$ and $O_2{^-}$ radicals among the other flavonoids. These results indicate that the flavonoids from A. okamotoanum, in particular IQ, would have a protective activity against oxidative stress induced by free radicals, and potentially be considered as a natural antioxidant agent.

• Natural Product Sciences
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• v.24 no.4
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• pp.235-240
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• 2018

Betula platyphylla var. japonica (Betulaceae), also known as Asian white birch, is an endemic medicinal tree, the bark of which has been used in Chinese traditional medicine for the treatment of various inflammatory diseases. In our continuing search for bioactive compounds from Korean natural resources, a phytochemical investigation of the bark of B. platyphylla var. japonica led to the isolation of 7-oxo-${\beta}$-sitosterol (1) and soyacerebroside I (2) from its ethanol extract as main components by liquid chromatography (LC)/mass spectrometry (MS)-based analysis. The structures of isolates were identified by comparison of $^1H$ and $^{13}C$ nuclear magnetic resonance spectroscopic data and physical data with the previously reported values and LC/MS analyses. To the best of our knowledge, this is the first study to demonstrate that the isolated compounds, 7-oxo-${\beta}$-sitosterol and soyacerebroside I, were isolated in B. platyphylla var. japonica. We examined the effects of the isolates on the regulation of adipocytes and osteoblast differentiation. These isolates (1 and 2) produced fewer lipid droplets compared to the untreated negative control in Oil Red O staining of the mouse mesenchymal stem cell line without altering the amount of alkaline phosphatase staining. The results demonstrated that both compounds showed marginal inhibitory effects on adipocyte differentiation but did not affect osteoblast differentiation.

• Parasites, Hosts and Diseases
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• v.60 no.4
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• pp.281-288
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• 2022

Malaria continues to be one of the most crucial infectious burdens in endemic areas worldwide, as well as for travelers visiting malaria transmission regions. It has been reported that 8-aminoquinolines are effective against the Plasmodium species, particularly primaquine, for anti-hypnozoite therapy in P. vivax malaria. However, primaquine causes acute hemolytic anemia in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency. Therefore, G6PD deficiency testing should precede hypnozoite elimination with 8-aminoquinoline. Several point-of-care devices have been developed to detect G6PD deficiency. The aim of the present study was to evaluate the performance of a novel, quantitative G6PD diagnostics based on a metagenomic blue fluorescent protein (mBFP). We comparatively evaluated the sensitivity and specificity of the G6PD diagnostic modality with standard methods using 120 human whole blood samples. The G6PD deficiency was spectrophotometrically confirmed. The performance of the G6PD quantitative test kit was compared with that of a licensed control medical device, the G6PD strip. The G6PD quantitative test kit had a sensitivity of 95% (95% confidence interval (CI): 89.3-100%) and a specificity of 100% (95% CI: 94.3-100%). This study shows that the novel diagnostic G6PD quantitative test kit could be a cost-effective and time-efficient, and universally mandated screening tool for G6PD deficiency.

• Korean Journal of Pharmacognosy
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• v.53 no.3
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• pp.153-161
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• 2022

Cotoneaster mongolicus Pojark. (CM), in the family Rosaceae is an endemic plant to the Mongolian region (its name: Moнroл чapraй). In Mongolia, Cotoneaster species as a crude drug is mainly used for inflammatory diseases, diarrhea, and stomach indigestion. In this study, we evaluated the gastro-protective activity underlying mechanism of CM. For in vivo experiments, mice were divided into 5 groups; normal mice (Normal), gastritis mice (Control), gastritis mice treated with sucralfate 10 mg/kg (SC), gastritis mice treated with CM 100 mg/kg (CML), gastritis mice treated with CM 200 mg/kg (CMH). Gastritis was provoked by HCl/ethanol (60% ethanol in 150 mM HCl). After oral administration of each drug, HCl/ethanol was orally administered 90 mins later to induce gastritis. CM alleviated the damage to the gastric mucosa caused. As a result of confirming the expression of protein in gastric tissue through western blot, CM significantly reduced the expression of NF-κB activated due to gastritis. Also, it significantly modulated the Nrf2-Keap1 pathway. These results indicate that CM not only inhibits the nuclear metastasis of NF-𝛋B but also modulates the Nrf2-Keap1 pathway to relieve inflammation of the gastric mucosa.

• Parasites, Hosts and Diseases
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• v.61 no.3
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• pp.263-271
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• 2023

The present study aimed to survey the prevalence of chigger mites and Orientia tsutsugamushi (O. tsutsugamushi) infection in the northern regions of Gangwon-do, Korea. From early February to early June 2015, a total of 17,050 chiggers were collected from striped field mice, Apodemus agrarius, in Cheorwon-gun, Hwacheon-gun, Yanggu-gun, and Goseong-gun, which are well-known endemic areas of scrub typhus in Korea. The chiggers were analyzed using molecular genomic methods, as previously described. Among the 7,964 identified chiggers, the predominant species was Leptotrombidium pallidum (76.9%), followed by L. zetum (16.4%), L. orientale (4.3%), L. palpale (0.3%), L. tectum (0.2%), and Neotrombicula tamiyai (1.8%). The chigger index (CI) was highest in Hwacheon (115.58), followed by Cheorwon (97.02), Yanggu (76.88), and Goseong (54.68). Out of the 79 O. tsutsugamushi-positive chigger pools, 67 (84.8%) were identified as the Boryong strain, 10 (12.7%) as the Youngworl strain, and only 2 were the Jecheon strain. Based on the high infestation of chiggers in striped field rodents and the high rate of O. tsutsugamushi infection in chigger mites, Hwacheon-gun and Cheorwon-gun are presumed to be high-risk areas for scrub typhus. Furthermore, L. pallidum, a major vector of scrub typhus, and the dominant O. tsutsugamushi serotype, the Boryong strain, were found in the northern regions of Gangwon-do, Korea.

• Journal of Microbiology and Biotechnology
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• v.33 no.10
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• pp.1299-1308
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• 2023

Carya cathayensis is an important economic nut tree that is endemic to eastern China. As such, outbreaks of root rot disease in C. cathayensis result in reduced yields and serious economic losses. Moreover, while soil bacterial communities play a crucial role in plant health and are associated with plant disease outbreaks, their diversity and composition in C. cathayensis are not clearly understood. In this study, Proteobacteria, Acidobacteria, and Actinobacteria were found to be the most dominant bacterial communities (accounting for approximately 80.32% of the total) in the root tissue, rhizosphere soil, and bulk soil of healthy C. cathayensis specimens. Further analysis revealed the abundance of genera belonging to Proteobacteria, namely, Acidibacter, Bradyrhizobium, Paraburkholderia, Sphaerotilus, and Steroidobacter, was higher in the root tissues of healthy C. cathayensis specimens than in those of diseased and dead trees. In addition, the abundance of four genera belonging to Actinobacteria, namely, Actinoallomurus, Actinomadura, Actinocrinis, and Gaiella, was significantly higher in the root tissues of healthy C. cathayensis specimens than in those of diseased and dead trees. Altogether, these results suggest that disruption in the balance of these bacterial communities may be associated with the development of root rot in C. cathayensis, and further, our study provides theoretical guidance for the isolation and control of pathogens and diseases related to this important tree species.

• Parasites, Hosts and Diseases
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• v.27 no.2
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• pp.109-118
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• 1989

Production of circulating specific antibodies to the lung fluke (Paragenimus westermani) by its host is well known and used in various kinds of immunodiagnostic methods, However, it has not been well documented which compartments (or structures) of the lung fluke are most responsible for the production of specific antibodies. The present immunohistochemical study was undertaken to demonstrate the antigenicity of each body compartment of p. westermani such as suckers, tegument, spines, vitelline glands, intestine, reproductive organs(male and female), and eggs. Indiret immunoperoxidase(IP) stain technique was applied, using formalin-fked, paraffin- embedded lung tissues of P westermani-infected cats sectioned in 4 Um thickness as the antigen and cat antisera (11~20 weeks of infection) as the primary antibody. Peroxidase-conjugated goat anti-cat IgG was used as the secondary antibody and diaminobensidine(DAB) as the coloring agent. Strong yellow or yellowish brown staining was regarded positive. The primary and secondary antibody dilutions were made at 1 : 500~1 : 2, 000 and 1 : 200~1 : 500 respectively, and IP stain was repeated 10 times for each dilution. A consistent result obtained was that the intestinal epithelial border, intestinal content, vitelline glands, and eggs scattered around the worm capsule showed strong positive staining, while uterine eggs and some parenchymal portions showed weak positive reaction. On the other hand, the suckers, tegument, spines, subtegumental cells, cytoplasm of intestinal epithelial cells, male reproductive organs, and ovary revealed negative staining. The body compartments showing higher antigenicity were, in the decreasing order, the intestinal epithelial border, intestinal content, eggs in the worm capsule, vitelline glands, uterine eggs, and parenchymatous portions. The intestinal epithelial border and luminal contents revealed positive staining even at a few concentration of 1 : 4, 000 primary antibody(secondary ab., 1 : 200) whereas the parenchymatous portion showed positive reaction only at higher concentrations than 1'500 (secondary ab., 1 : 200). The results suggest that the specific antibody responses of the host to p. westermani occur most strongly upon the excretes from the intestinal epithelium of the worm and e99s Produced around the worm capsule,

• Tuberculosis and Respiratory Diseases
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• v.52 no.4
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• pp.367-375
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• 2002

Background : Murine typhus is a flea-borne, worldwide Rickettsial disease caused by Rickettsia typhi. Its symptoms are typically mild but sometimes can be fatal. The major clinical features include fever, rash, and headache. Recently, we experienced 6 cases of ARDS associated with a Rickettsia typhi infection. This study was aimed to analyze the attributing factors for fatal murine typhus and to review the characteristics of the patients who showed acute respiratory distress syndrome as the initial presentation. Methods : The medical records of 15 patients diagnosed as murine typhus were reviewed. The diagnosis was made by single titers of 1:512 or higher, or a 4-fold rise with compatible clinical features. Acute Respiratory Distress Syndrome (ARDS) was defined according to the American-European Consensus Conference. The Characteristics between the ARDS group and the non-ARDS group of murine typhus were compared. Results : Six patients developed ARDS as their initial presentation. Two of them were women and three of them had lived urban area. None of Them a showed skin rash. One of them expired during treatment. The time lapse until the commencement of the specific treatment, the lower serum albumin level, the higher serum total bilirubin level, the higher APACHE III score and the higher MOD score were significantly associated with the ARDS group compared to the non-ARDS group. Conclusion : Murine typhus should be considered as one of the etiologies for the ARDS of unknown cause, particularly in an endemic regions. ARDS caused by Murine typhus generally has a good prognosis.