• Economic and Environmental Geology
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• v.57 no.1
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• pp.41-50
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• 2024

This study reports the structural geometry and folding mechanism of a regional-scale overturned fold in the Daecheong Island, central-western part of the Korean Peninsula. Based on low-hemisphere stereographic and down-plunge projections using data from a detailed field survey, we classify the regional-scale fold as an open overturned fold shallowly plunging toward NE. The asymmetric and symmetric parasitic folds in the limb and hinge zones indicate layer-parallel shortening prior to flexural-flow folding. Fold dating must be required to decipher the orogenic process causing the regional-scale overturned fold in the Daecheong Island.

• Parasites, Hosts and Diseases
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• v.61 no.3
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• pp.304-309
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• 2023

Intestinal parasitic infections are a public health burden and a major cause of illness in developing countries. The diseases lead to various health threats, including growth retardation and mental health-related disorders, especially in children. We assessed the risk factors for intestinal parasitic infections among children aged 12-59 months residing in Nyamasheke District, Rwanda. A cross-sectional descriptive study was conducted using secondary data from 1,048 children aged 12-59 months whose stool samples were examined for the presence of intestinal parasites and whose results were registered in the laboratory information system in 2020. The prevalence of intestinal parasites in children aged 12-59 months was 53.2%. The dominant parasites were Ascaris lumbricoides (13.1%), followed by Giardia lamblia (10.9%), Entamoeba histolytica (7.9%), Trichuris trichiura (6.5%), hookworms (1.7%), and Taenia species (1.4%). A significant association was observed between intestinal parasites and the literacy of mothers or children's caregivers (odds ratio (OR)=5.09, P<0.001). Children from farming households were 2.8-fold more likely to contract intestinal parasitic infections than those from nonfarming households (OR=2.8, P<0.001). A significant association was also observed between intestinal parasites and food safety (OR=4.9, P<0.001). Intestinal parasitic infections were significantly associated with hand hygiene practices after using the toilet and washing fresh fruits before eating (P<0.001). The information gathered will help public health providers and partners develop control plans in highly endemic areas in Rwanda.

• Parasites, Hosts and Diseases
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• v.57 no.3
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• pp.243-248
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• 2019

The purpose of this study was 2-fold: 1) to investigate the prevalence of gastrointestinal parasite infection in cats reared in Daegu, Republic of Korea and 2) to assess the efficacy and safety of a topical emodepside/praziquantel formulation for cats with parasitic infections. The gastrointestinal parasite infections were examined microscopically using the flotation method. Of 407 cats, 162 (39.8%) were infected by at least one gastrointestinal parasite, including Toxocara cati (63.0%), Toxascaris leonina (31.5%), Taenia taeniaeformis (3.7%), and Cystoisospora felis (1.9%). None of the infected animals had multiple infections. When the data were analyzed according to sex, age, and type of cat, stray cats showed statistically higher prevalence than companion cats (P<0.05). On the 5th day after treatment, no parasitic eggs were detected using microscopic examination. In addition, no adverse effects, such as abnormal behaviors and clinical symptoms, were observed in the cats treated with the drug. These results quantify the prevalence of gastrointestinal parasites in cats in Daegu, Republic of Korea, and show that topical emodepside/praziquantel is a safe and effective choice for treating the parasitic infections in cats.

• Parasites, Hosts and Diseases
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• v.57 no.5
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• pp.489-497
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• 2019

Cystic echinococcosis (CE), a zoonotic disease caused by Echinococcus granulosus at the larval stage, predominantly develops in the liver and lungs of intermediate hosts and eventually results in organ malfunction or even death. The interaction between E. granulosus and human body is incompletely understood. Exosomes are nanosized particles ubiquitously present in human body fluids. Exosomes carry biomolecules that facilitate communication between cells. To the best of our knowledge, the role of exosomes in patients with CE is not reported. Here, we isolated exosomes from the sera of patients with CE (CE-exo) and healthy donors and subjected them to liquid chromatography-tandem mass spectrometry analysis. Proteomic analysis identified 49 proteins specifically expressed in CE-exo, including 4 proteins of parasitic origin. The most valuable parasitic proteins included tubulin alpha-1C chain and histone H4. And 8 proteins were differentially regulated in CE-exo (fold change>1.5), as analyzed with bioinformatic methods such as annotation and functional enrichment analyses. These findings may improve our understanding about the interaction between E. granulosus and human body, and may contribute to the diagnosis and prevention of CE.

• The Journal of Korean Medicine
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• v.19 no.1
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• pp.419-429
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• 1998

Poncirus trifoliata (L.) Raf (Rutaceae) fruits (PTFE) has been used for the treatment of allergic disease. IgE is normally one of the least abundant immunoglobulin (Ig) isotypes in the serum of both humans and several species of experimental animals: however a number of different stimuli can result in profound increases in IgE levels relative to other isotypes. In rodents, infection with many parasitic helminths can cause approximately 100-fold elevation in IgE within 2 wks. Immunization of mice with small amounts of protein antigens on alum also results in 10-fold to fold increase in total serum IgE, much of it specific for the immunizing antigen. In this experiment, I investigated the effect of an aqueous extract of Poncirus trifoliata (L.) Raf (Rutaceae) fruits (PTFE) on a in vivo and in vitro IgE production. PTFE dose-dependently inhibited the serum levels of IgE induced by antigens. The regulation of IgE synthesis is influenced by T cells and T cell derived factors. IL -4, a T cell-derived cytokine, has been shown to stimulate murine IgE synthesis both in vitro and in vivo. Current evidence suggests that IL-4 induces IgE synthesis in the mouse by stimulating H chain isotype switch. Lipopolysaccharide (LPS) plus IL-4 cause about l00-fold increase in IgE secretion by murine B cells. The effects of PTFE on the IL-4-dependent IgE response by mouse whole spleen cells were studied. Whole spleen cells were cultured for 7 days in the presence of LPS plus IL-4 and PTFE and the supernatants were assayed for IgE. IL-4 dependent IgE production of LPS-stimulated whole spleen cells was inhibited by PTFE. Moreover, in the present study using U266Bl human IgE-bearing B cells, I found that PTFE inhibited the production of IgE activated by LPS plus IL-4. These results indicate that PTFE have antiallergic activity by inhibition of IgE production from B cells.

• Fisheries and Aquatic Sciences
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• v.20 no.7
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• pp.12.1-12.7
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• 2017

Soft tunic syndrome (STS) is a protozoal disease caused by Azumiobodo hoyamushi in the edible ascidian Halocynthia roretzi. Previous studies have proven that combined formalin-hydrogen peroxide ($H_2O_2$) bath is effective in reducing STS progress and mortality. To secure target animal safety for field applications, toxicity of the treatment needs to be evaluated. Healthy ascidians were bathed for 1 week, 1 h a day at various bathing concentrations. Bathing with 5- and 10-fold optimum concentration caused 100% mortality of ascidians, whereas mortality by 0.5- to 2.0-fold solutions was not different from that of control. Of the oxidative damage parameters, MDA levels did not change after 0.5- and 1.0-fold bathing. However, free radical scavenging ability and reducing power were significantly decreased even with the lower-than-optimal 0.5-fold concentration. Glycogen content tended to increase with 1-fold bathing without statistical significance. All changes induced by the 2-fold bathing were completely or partially restored to control levels 48 h post-bathing. Free amino acid analysis revealed a concentration-dependent decline in aspartic acid and cysteine levels. In contrast, alanine and valine levels increased after the 2-fold bath treatment. These data indicate that the currently established effective disinfectant regimen against the parasitic pathogen is generally safe, and the biochemical changes observed are transient, lasting approximately 48 h at most. Low levels of formalin and $H_2O_2$ were detectable 1 h post-bathing; however, the compounds were completely undetectable after 48 h of bathing. Formalin-$H_2O_2$ bathing is effective against STS; however, reasonable care is required in the treatment to avoid unwanted toxicity. Drug residues do not present a concern for consumer safety.

• Korean Journal of Veterinary Research
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• v.49 no.3
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• pp.253-256
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• 2009

The aim of the present study was to determine the acute and subacute potential of trichlorfon in guppies (Poecilia reticulatus). We first defined the 24 h median tolerance limit ($TLm_{24h}$) of the fish to trichlorfon. Guppies were then treated with $TLm_{24h}$ and 1/10 $TLm_{24h}$ trichlorfon concentrations to evaluate if any histological alterations occurred. The $TLm_{24h}$ value of trichlorfon was 11 ppm. This concentration resulted in acute toxicity to the gills and kidneys with edema, hyperplasia of the gill lamellae, and vacuolated degeneration and necrosis of renal tubular cells. In the case of subacute toxicity using a 10-fold dilution of the $TLm_{24h}$ value (1.1 ppm), no behavioral changes, external lesions or histopathological changes were observed. Therefore, safe concentration of trichlorfon might be 1.1 ppm in guppy for controlling parasitic infections.

• Journal of Life Science
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• v.10 no.4
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• pp.403-407
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• 2000

For the biological control of the root-lesion nematodes, Pratylenchus spp., which damage directly and indirectly to the leaf perilla, the nematical effect of three nematode-trapping fungi, Arthrobotrys oligospora, A. conoides and A. dactyloides was evaluated in the field. Three species of Arthrobotrys were isolated from the culture soil of leaf perilla in 1998 and were observed the capture of the root-lesion nematodes, Pratylenchus spp. by adhesive hyphal networks or constricting rings on agar. At 40 days after treatment, the plant-parasitic nematodes and root-lesion nematode populations were approximately increased 3.5 fold in untreated control plot, while the nematode population in fungi treatment plots was similar to initial population. In the A. dactyloides plot, however, the population of plant-parasitic nematodes and Pratylenchus spp. was approximately reduced 65% and 53%, respectively. Thus, the fungus A. dachyloides should provide as biological agent for the control of Pratylenchus spp.

• Journal of Veterinary Science
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• v.22 no.3
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• pp.40.1-40.12
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• 2021

Background: The microsporidian parasite Nosema ceranae is a global problem in honeybee populations and is known to cause winter mortality. A sensitive and rapid tool for stable quantitative detection is necessary to establish further research related to the diagnosis, prevention, and treatment of this pathogen. Objectives: The present study aimed to develop a quantitative method that incorporates ultra-rapid real-time quantitative polymerase chain reaction (UR-qPCR) for the rapid enumeration of N. ceranae in infected bees. Methods: A procedure for UR-qPCR detection of N. ceranae was developed, and the advantages of molecular detection were evaluated in comparison with microscopic enumeration. Results: UR-qPCR was more sensitive than microscopic enumeration for detecting two copies of N. ceranae DNA and 24 spores per bee. Meanwhile, the limit of detection by microscopy was 2.40 × 10⁴ spores/bee, and the stable detection level was ≥ 2.40 × 10⁵ spores/bee. The results of N. ceranae calculations from the infected honeybees and purified spores by UR-qPCR showed that the DNA copy number was approximately 8-fold higher than the spore count. Additionally, honeybees infected with N. ceranae with 2.74 × 10⁴ copies of N. ceranae DNA were incapable of detection by microscopy. The results of quantitative analysis using UR-qPCR were accomplished within 20 min. Conclusions: UR-qPCR is expected to be the most rapid molecular method for Nosema detection and has been developed for diagnosing nosemosis at low levels of infection.

• The Korean Journal of Malacology
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• v.27 no.4
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• pp.387-393
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• 2011

The objective of this study was to develop a real-time PCR method for the rapid detection and quantification of the protozoan pathogen Perkinsus olseni using a TaqMan probe. For the standard, genomic DNA was extracted from $10^5$ in vitro-cultured P. olseni trophozoites, and then 10-fold serial dilutions to the level of a single cell were prepared. To test the reliability of the technique, triplicates of genomic DNA were extracted from $5{\times}10^4$ cells and 10-fold serial dilutions to the level of 5 cells were prepared. The standards and samples were analyzed in duplicate using an $Exicycler^{TM}$ 96 real-time quantitative thermal block. For quantification, the threshold cycle ($C_T$) values of samples were compared with those obtained from standard dilutions. There was a strong linear relationship between the $C_T$ value and the log concentration of cells in the standard ($r^2$ = 0.996). Detection of DNA at a concentration as low as the equivalent of a single cell showed that the assay was sensitive enough to detect a single cell of P. olseni. The estimated number of P. olseni cells was similar to the original cell concentrations, indicating the reliability of P. olseni quantification by real-time PCR. Accordingly, the designed primers and probe may be used for the rapid detection and quantification of P. olseni from clam tissue, environmental water, and sediment samples.