• Journal of fish pathology
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• v.10 no.2
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• pp.137-142
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• 1997

A monogenean gill parasite, Prosomicrocotyla gotoi, and a digenean intestinal fluke. Opecoelus sphaericus, were found from greenilngs (Hexagrammos otakii) captured at the Korean southern sea. P. gotoi was characterized by having two separated frills of opisthaptor and distinguished from P. chirii in testis and clamp numbers. O. sphaericus had three pairs of finger-like marginal appendages on the ventral sucker and the parasite was distinguished from O. nipponicus in the location pattern of testes. These two helminth species were the first recording species in Korea.

• Parasites, Hosts and Diseases
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• v.43 no.4 s.136
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• pp.141-147
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• 2005

A practical and convenient method of rearing Eucyclops serrulatus in a microculture environment is described. A complete life cycle of E. serrulatus was maintained in a narrow space on a microscope slide glass on which a cover glass of $22{\times}40mm$ in size was mounted at a height of 0.8mm. The culture medium was constituted by bottled mineral water boiled with grains of Glycine max (soybean). Chilomonas paramecium, a free-living protozoan organism, was provided as live food. Growth of nauplii hatched from eggs to the first stage of copepodite took an average of 7.7 days, and the growth of copepodite 1 to the egg-bearing adult female took an average of 20.1 days in the microculture cell with an average life time of 44.7 days. Continuous passage of cope pods was successfully maintained as long as sufficient medium and food were provided. The microculture method enables an in situ microscopic observation on the growth and developmental process of helminth larvae experimentally infected to copepods as well as of copepod itself. Furthermore, it does not require anesthetization and, therefore, minimize the amount of stress exposed to cope pods during the handling process.

• Parasites, Hosts and Diseases
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• v.52 no.5
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• pp.569-573
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• 2014

In a paleo-parasitological analysis of soil samples obtained from V-shaped pits dating to the ancient Baekje period in Korean history, we discovered Ascaris lumbricoides, Trichuris trichiura, and Clonorchis sinensis eggs. In light of the samples' seriously contaminated state, the V-shaped pits might have served as toilets, cesspits, or dung heaps. For a long period of time, researchers scouring archaeological sites in Korea have had difficulties locating such structures. In this context then, the present report is unique because similar kind of the ancient ruins must become an ideal resource for successful sampling in our forthcoming paleoparasitological studies.

• Parasites, Hosts and Diseases
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• v.51 no.6
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• pp.663-667
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• 2013

Free-grazing ducks play a major role in the rural economy of Eastern Asia in the form of egg and meat production. In Thailand, the geographical location, tropical climate conditions and wetland areas of the country are suitable for their husbandry. These environmental factors also favor growth, multiplication, development, survival, and spread of duck parasites. In this study, a total of 90 free-grazing ducks from northern, central, and northeastern regions of Thailand were examined for intestinal helminth parasites, with special emphasis on zoonotic echinostomes. Of these, 51 (56.7%) were infected by one or more species of zoonotic echinostomes, Echinostoma revolutum, Echinoparyphium recurvatum, and Hypoderaeum conoideum. Echinostomes found were identified using morphological criteria when possible. ITS2 sequences were used to identify juvenile and incomplete worms. The prevalence of infection was relatively high in each region, namely, north, central, and northeast region was 63.2%, 54.5%, and 55.3%, respectively. The intensity of infection ranged up to 49 worms/infected duck. Free-grazing ducks clearly play an important role in the life cycle maintenance, spread, and transmission of these medically important echinostomes in Thailand.

• Parasites, Hosts and Diseases
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• v.46 no.1
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• pp.1-15
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• 2008

Introduction of double-stranded RNA (dsRNA) into some cells or organisms results in degradation of its homologous mRNA, a process called RNA interference (RNAi). The dsRNAs are processed into short interfering RNAs (siRNAs) that subsequently bind to the RNA-induced silencing complex (RISC), causing degradation of target mRNAs. Because of this sequence-specific ability to silence target genes, RNAi has been extensively used to study gene functions and has the potential to control disease pathogens or vectors. With this promise of RNAi to control pathogens and vectors, this paper reviews the current status of RNAi in protozoans, animal parasitic helminths and disease-transmitting vectors, such as insects. Many pathogens and vectors cause severe parasitic diseases in tropical regions and it is difficult to control once the host has been invaded. Intracellularly, RNAi can be highly effective in impeding parasitic development and proliferation within the host. To fully realize its potential as a means to control tropical diseases, appropriate delivery methods for RNAi should be developed, and possible off-target effects should be minimized for specific gene suppression. RNAi can also be utilized to reduce vector competence to interfere with disease transmission, as genes critical for pathogenesis of tropical diseases are knockdowned via RNAi.

• Parasites, Hosts and Diseases
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• v.22 no.2
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• pp.215-222
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• 1984

During February 1982 to September 1983, a total of 105 domestic ducks (Anas platyrhynchos var. domestica Linnaeus) were collected from Ichon Gun, Pusan City, Chunchon City, Yanggu Gun, Taejeon City and unknown areas in Korea. In the results, six trematode and one nematode species of helminth parasites were obtained and described as follows: Amphimerus anatis Yamaguti, 1933, Echinostoma miyagawai Ishii, 1932, Echinochasmus japonicus Tanabe, 1926, Cryptocotyle sp., Notocotylus attenuatus (Rudolphi, 1809) Kossack, 1911, Apatemon sp. and nematode species, Heterakis gallinarum Schrank, 1788. From this collection, Amphimerus anatis Yamaguti, 1933, Echinochasmus japonicus Tanabe, 1926, genus Cryptocotyle Liihe, 1899 and genus Apatemon Szidat, 1928 were firstly recorded in Korea.

• Parasites, Hosts and Diseases
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• v.24 no.2
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• pp.209-212
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• 1986

The present study was undertaken to evaluate the present status of intestinal parasitic infection in Seoul area, Korea. During the period from June 1985 to July 1986, a total of 5,251 stool samples were collected in Department of Clinical Pathology, Hanyang University Hospital and examined by formalin-ether sedimentation technique once for helminth ova and protozoan cysts. The results were summarized as follows: 1. The overall egg positive rate of intestinal helminthes was 2.53%; and 1.43% for Clonorchis sinensis, 0.7% for Trichuris trichiura, 0.13% for Metagonimus yokogawai, 0.06% for hookworm, and 0.02% for Ascaris lumbricoides, Diphyllobothrium latum and Hymenolepis nana, respectively. 2. The overall cyst positive rate of intestinal protozoa was 1.07%. Cyst positive rate was 0.06% for Entamoeba histolytica and 0.13% for Giardia lamblia, respectively. 3. Higher prevalence of intestinal parasitic infection was observed in male and in $21{\sim}50$ year-old groups. 4. The highest prevalence of Clonorchis sinensis infection was observed in 40th age group (3.4%), and male (2.3%) was more infected than female (0.7%) in general.

• Parasites, Hosts and Diseases
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• v.55 no.5
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• pp.569-573
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• 2017

The present study was performed to reveal the current status and risk factors of Strongyloides stercoralis infections in the villages of Kenethao district, Xayaburi Province, Lao PDR. Fecal specimens were collected and examined for S. stercoralis using Koga-agar plate culture technique. Among 516 individuals, the prevalence of S. stercoralis and hookworm infection was 44.2% and 17.1%, respectively. Co-infection was detected in 13.2% of the cases. The prevalence did not significantly differ between males and females (P=0.193). However, the prevalence of S. stercoralis infection increased significantly with age (P=0.041). Of the risk factors examined, both performing farming activities (P=0.001) and walking barefoot when going outside of the house (P=0.003) showed significant correlations with S. stercoralis infections. Our results suggest that S. stercoralis is highly endemic in this area. The National Helminth Control Program of Lao PDR should take actions to control S. stercoralis infection. In addition, provision of health education about the benefits of wearing shoes would be important for reducing infection in the study area. Moreover, the application of high-sensitivity diagnostic approaches is needed to obtain the true impact of S. stercoralis infections in all rural communities in order to provide surveillance activities in Lao PDR.

• Parasites, Hosts and Diseases
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• v.33 no.1
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• pp.65-68
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• 1995

We examined stool specimens of the residents in the emigi·ation camp in Tijuana, Mexico for helminth eggs or protozoan cysts with formalin-ethyl acetate concentration method in February and July 1992. Out of 92 examined samples, number of positive was 49 (53.3%). While number of cumulative positive was 66 (71.7%). Cysts of Entnmoeba coli (29.3%) Giardio lomblia (9.8%), Entamoebo histolytica (7.6%), and eggs of Tqenic app. (6.5) were most frequently observed. Filtered water supply and chemotherapy were required in this camp.

• Research in Community and Public Health Nursing
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• v.14 no.3
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• pp.457-467
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• 2003

Purpose: This study examined the development and performance of the school health promotion policy guideline that is applicable to Korean school health. Methods: 1. The WHO's guideline was translated into Korean and modified by school health experts 2. A questionnaire was conducted to assess the performance of school health policy on 207 nurses in elementary schools in Seoul and Cheonbuk. Result: The Korean version of the school health promotion policy guidelines were developed including 9 components and 36 checkpoints. Compared to that of WHO, the component 'school nursing teacher' was added and three components were eliminated: 'equitable access to school resources', 'control of helminth', and 'sun protection policy'. The performance degree of first-aid, closure of school in a calamity, and control of HIV/AIDS was very low. The performance degree of a healthy diet, and regular physical examination was quite high. This study was the first that developed the school health promotion policy guideline and examined the performance. Further research is needed to validate the guidelines developed by this study.