• Parasites, Hosts and Diseases
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• v.50 no.4
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• pp.317-325
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• 2012

The prevalence of foodborne trematode (FBT) metacercariae was investigated in fish from 2 localities of northern Vietnam in 2004-2005. Freshwater fish (9 species) were collected from local markets in Hanoi City (n=76) and Nam Dinh Province (n=79), and were examined for FBT metacercariae using the artificial digestion technique. Adult flukes were obtained from hamsters experimentally infected with the metacercariae at day 8 post-infection. Three (Haplorchis pumilio, Centrocestus formosanus, and Procerovum varium) and 6 (Haplorchis taichui, H. pumilio, C. formosanus, P. varium, Stellantchasmus falcatus, and Heterophyopsis continua) species of FBT metacercariae were detected in the 2 regions, respectively. Overall, among the positive fish species, H. pumilio metacercariae were detected in 104 (80.0%) of 130 fish examined (metacercarial density per infected fish; 64.2). C. formosanus metacercariae were found in 37 (40.2%) of 92 fish (metacercarial density; 14.7). P. varium metacercariae were detected in 19 (63.3%) of 30 fish (Anabas testudineus and Mugil cephalus) (metacercarial density; 247.7). S. falcatus metacercariae were found in all 10 M. cephalus examined (metacercarial density; 84.4). H. continua metacercariae (2 in number) were detected in 1 fish of Coilia lindmani. Morphologic characteristics of the FBT metacercariae and their experimentally obtained adults were described. The results have demonstrated that various FBT species are prevalent in northen parts of Vietnam.

• Journal of Life Science
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• v.18 no.6
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• pp.759-763
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• 2008

Halophila ovalis (R. Br.) Hook. fil. was first collected from the Ando, Yeosu, Korea in 2007. H. ovalis is Widely distributed from sub-tropical to even tropical areas and produces the seeds using bisexual reproduction. Its leaf shape was oblong to ovate. Its leaf blades were rigid in texture, with a strong support to the leaf. Erect shoots arose at irregular intervals along the rhizome. The distance between the intramarginal vein and leaves margin was small. Nucleotides in ITS 1 and ITS 2 regions between the Korean and Japanese H. ovalis were found to be 100% similar, whereas Korean H. ovalis was found to have four nucleotides in the positions of 202 bp to 206 bp for 5.8S. In the analysis of the phylogenetic relationship using NJ method, Korean H. ovalis had a monophyletic genetic tree with Japanese H. ovalis, but no phylogenetic relationship with types from the Philippines, Australia, Malaysia, and Vietnam. The first occurrence of H. ovalisin Korea was associated with a strong migration of gene flow from Japan and high water temperature caused by the variations in climate.

• The Plant Pathology Journal
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• v.28 no.2
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• pp.123-136
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• 2012

Diseases caused by begomoviruses (family Geminiviridae, genus Begomovirus) constitute a serious constraint to tropical and sub-tropical agro-ecosystems worldwide. In recent years, they have also introduced in temperate regions of the world where they have great impact and are posing a serious threat to a variety of greenhouse crops. Begomoviral diseases can in extreme cases reduce yields to zero leading to catastrophic losses in agriculture. They are still evolving and pose a serious threat to sustainable agriculture across the world, particularly in tropics and sub-tropics. Till recently, there have been no records on the occurrence of begomoviral disease in South Korea, however, the etiology of other plant viral diseases are known since last century. The first begomovirus infected sample was collected from sweet potato plant in 2003 and since then there has been gradual increase in the begomoviral epidemics specially in tomato and sweet potato crops. So far, 48 begomovirus sequences originating from various plant species have been submitted in public sequence data base from different parts of the country. The rapid emergence of begomoviral epidemics might be with some of the factors like evolution of new variants of the viruses, appearance of efficient vectors, changing cropping systems, introduction of susceptible plant varieties, increase in global trade in agricultural products, intercontinental transportation networks, and changes in global climatic conditions. Another concern might be the emergence of a begomovirus complex and satellite DNA molecules. Thorough understanding of the pathosystems is needed for the designing of effective managements. Efforts should also be made towards the integration of the resistant genes for the development of transgenic plants specially tomato and sweet potato as they have been found to be widely infected in South Korea. There should be efficient surveillance for emergence or incursions of other begomoviruses and biotypes of whitefly. This review discusses the general characteristics of begomoviruses, transmission by their vector B. tabaci with an especial emphasis on the occurrence and distribution of begomoviruses in South Korea, and control measures that must be addressed in order to develop more sustainable management strategies.

• Parasites, Hosts and Diseases
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• v.56 no.3
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• pp.295-300
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• 2018

Human sparganosis was diagnosed by morphological and genetic analyses in Korea. The complete mitochondrial genomes of Spirometra erinaceieuropaei and S. decipiens isolated in Korea have been recorded. Present study was performed to provide information to diagnose the etiologic agent of sparganosis by multiplex PCR using mitochondrial genome sequences of S. erinaceieuropaei and S. decipiens. In an effort to examine the differential diagnosis of spirometrid tapeworms, multiplex PCR assays were performed on plerocercoid larvae of S. erinaceieuropaei and S. decipiens. The PCR products obtained using species-specific primers were positively detected in all PCR assays on mixture of S. erinaceieuropaei and S. decipiens DNA. S. erinaceieuropaei-specific bands (239 bp and 401 bp) were obtained from all PCR assays using a mixture of S. erinaceieuropaei-specific primers (Se/Sd-1800F and Se-2018R; Se/Sd-7955F and Se-8356R) and S. erinaceieuropaei template DNA. S. decipiens-specific bands (540 bp and 644 bp) were also detected in all PCR assays containing mixtures of S. decipiens-specific primers (Se/Sd-1800F and Sd-2317R; Se/Sd-7955F and Sd-8567R) and S. decipiens template DNA. Sequence analyses on these species-specific bands revealed 100% sequence identity with homologous regions of the mtDNA sequences of S. erinaceieuropaei and S. decipiens. The multiplex PCR assay was useful for differential diagnosis of human sparganosis by detecting different sizes in species-specific bands.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.4
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• pp.319-325
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• 2015

Among solute carrier proteins, the organic anion transporters (OATs) play an important role for the elimination or reabsorption of endogenous and exogenous negatively charged anionic compounds. Among OATs, SLC22A9 (hOAT7) transports estrone sulfate with high affinity. The net decrease of estrogen, especially in post-menopausal women induces rapid bone loss. The present study was performed to search the SNP within exon regions of SLC22A9 in Korean females with osteoporosis. Fifty healthy controls and 50 osteoporosis patients were screened for the genetic polymorphism in the coding region of SLC22A9 using GC-clamped PCR and denaturing gradient gel electrophoresis (DGGE). Six SNPs were found on the SLC22A9 gene from Korean women with/without osteoporosis. The SNPs were located as follows: two SNPs in the osteoporosis group (A645G and T1277C), three SNPs in the control group (G1449T, C1467T and C1487T) and one SNP in both the osteoporosis and control groups (G767A). The G767A, T1277C and C1487T SNPs result in an amino acid substitution, from synonymous vs nonsynonymous substitution arginine to glutamine (R256Q), phenylalanine to serine (F426S) and proline to leucine (P496L), respectively. The Km values and Vmax of the wild type, R256Q, P496L and F426S were 8.84, 8.87, 9.83 and $12.74{\mu}M$, and 1.97, 1.96, 2.06 and 1.55 pmol/oocyte/h, respectively. The present study demonstrates that the SLC22A9 variant F426S is causing inter-individual variation that is leading to the differences in transport of the steroid sulfate conjugate (estrone sulfate) and, therefore this could be used as a marker for certain disease including osteoporosis.

• Parasites, Hosts and Diseases
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• v.58 no.2
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• pp.121-127
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• 2020

Pakistan is at intersection of hyperendemic regions for hydatidosis. Current study aimed to determine the prevalence of hydatid cysts and cyst characteristics in different intermediate hosts (sheep, goats, cattle and buffaloes) across the 4 provinces of Pakistan. A total of 991 sheep, 1,478 goats, 1,602 cattle and 1,343 buffaloes were examined for presence of hydatid cysts during 2 years (January 2016-December 2018). Differences in frequency of hydatidosis were observed with highest overall prevalence in buffaloes (11.9%) and sheep (11.5%). Highest prevalence and burden of infection were observed in older age animals (23.8%, 9.78±0.49) and females (26.5%, 12.53±0.67). Data for seasonal prevalence alluded to year-round presence of disease with non-significant statistical difference. Organ predilection indicated liver as the most preferred site of cyst localization followed mainly by lungs. An over-dispersion pattern was observed in all infected animals as majority of cysts belonged <10 cysts per infected host category. Highest percentage of fertile cysts was observed in liver of sheep. Interestingly, solitary form of cysts had higher fertility rate than multiple form. Amid lack of data and wide gap of knowledge, this study would try to fill up the lacunae regarding this neglected tropical disease. Extensive rearing of livestock, unregulated official slaughter and home slaughtering have played role in adaptability of E. granulosus in Pakistan.

• Pediatric Infection and Vaccine
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• v.18 no.2
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• pp.207-211
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• 2011

Dengue is an acute febrile viral disease which is found in tropical and sub-tropical regions around the world. Dengue fever has steadily increased in both incidence and distribution over the past 50 years. Even though Korea is not an endemic country for dengue fever, with the increasing numbers of overseas travelers in Korea, the numbers of imported dengue cases are steadily increasing. Here, we report a case of imported dengue hemorrhagic fever in a Korean child presenting with fever and epistaxis. Dengue fever should be considered if a patient who has a recent travel history to endemic areas showed classical symptoms.

• Journal of Korean Medical Science
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• v.33 no.44
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• pp.273.1-273.15
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• 2018

Background: Sparganosis is a larval cestodiasis caused by the plerocercoid of Spirometra spp. Since the first description of human sparganosis in 1924, several hundred cases have been reported in Korea. However, systematic approaches for literature surveys of Korean sparganosis have seldom appeared. Methods: We searched publicly available databases such as PubMed, Research Information Sharing Service, and Korea Medical Citation Index with relevant Medical Subject Headings. Results: At least 438 Korean sparganosis cases have been described from 1924 to 2015. Preoperative diagnosis has been significantly increased since the 1980s due to popularization of serological and imaging diagnostics. Cases were largely detected from fifth decades in general, but cerebral sparganosis was detected in relatively young age groups (third and fourth decades). Sparganosis was prevalent in men (75.9%). Consumption of frog/snake and drinking unfiltered water were found in 63.4% and 16.9% of patients, respectively. Most frequently affected sites were subcutaneous tissues (49.9%), followed by the central nervous system (36.2%). Involvements of visceral organs (7.6%), ocular regions (3.6%), and muscles (2.7%) were noticed. In women, breast sparganosis constituted a large proportion (34.2%). Sparganosis associated with immunocompromised patients has recently been reported. Conclusion: Sparganosis has been continuously reported in Korea during the past 90 years, although its incidence has decreased during the last 20 years. The disease is mostly characterized by subcutaneous nodule, but infection of the worm in vital organs often results in serious illness. Continuous awareness is warranted to monitor sparganosis occurrence and associated clinical consequences.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.234-234
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• 2015

The global patterns of annual and extreme precipitation are projected to be altered by climate change. There are various weather systems which bring precipitation (e.g. tropical cyclone, extratropical cyclone, etc.). It is possible in some regions that multiple weather systems affect the changes of precipitation. However, previous studies have assessed only the changes of precipitation associated with individual weather systems. The relative contributions of the weather systems to the changes of precipitation have not been quantified yet. Also, the changes of the relative importance of weather systems have not been assessed. This study present the quantitative estimates of 1) the relative contributions of weather systems (tropical cyclone (TC), extratropical cyclone (ExC), and "others") to the future changes of annual and extreme precipitation and 2) the changes of the proportions of precipitation associated with each weather system in annual and extreme precipitation based on CMIP5 generation GCM outputs. Weather systems are objectively detected from twelve GCM outputs and six models are selected for further analysis considering the reproducibility of weather systems. In general, the weather system which is dominant in terms of producing precipitation in the present climate contributes the most to the changes of annual and extreme precipitation in each region. However, there are exceptions for the tendency. In East Asia, "others", which ranks the second in the proportion of annual precipitation in present climate, has the largest contribution to the increase of annual precipitation. It was found that the increase of the "others" annual precipitation in East Asia is mainly explained by the changes of that in summer season (JJA), most of which can be regarded as the summer monsoon precipitation. In Southeast Asia, "others" precipitation, the second dominant system in the present climate, has the largest contribution to the changes of very heavy precipitation (>99.9 percentile daily precipitation of historical period). Notable changes of the proportions of precipitation associated with each weather system are found mainly in subtropics, which can be regarded as the "hotspot" of the precipitation regime shift.

• Parasites, Hosts and Diseases
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• v.59 no.5
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• pp.519-522
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• 2021

The Chinese edible frogs, Hoplobatrachus rugulosus (n=20), and the striped snakehead fish, Channa striata (n=34), were purchased from local markets in 3 administrative regions of Cambodia (Phnom Penh, Pursat, and Takeo Provinces) from May 2017 to April 2019, and their infection status with Gnathostoma sp. larvae was investigated. The frogs and fish were transported to the laboratory with ice and examined using the artificial digestion method. Advanced 3rd-stage larvae (AdL₃) of Gnathostoma spinigerum, 24 in total number (1-6 larvae/frog), were detected from 6 (60.0%) out of 10 frogs purchased from Phnom Penh. No gnathostome larvae were detected in 10 frogs purchased from Takeo Province and 34 snakeheads from Phnom Penh, Pursat, and Takeo Provinces. AdL₃ isolated from the frogs were 2.55-3.90 mm long and 0.31-0.36 mm wide. They had a characteristic head bulb (0.081×0.191 mm in average size) with 4 rows of hooklets, a muscular long esophagus (0.950-1.230 mm long), and 2 pairs of cervical sacs (0.530-0.890 mm long). The average number of hooklets in the 1st, 2nd, 3rd, and 4th rows was 41, 45, 48, and 51, respectively. These features were consistent with G. spinigerum AdL₃. By the present study, it has been first confirmed that the Chinese edible frog, H. rugulosus, from Phnom Penh serves as a second intermediate host for G. spinigerum, although their intensity of infection was not so high compared to other previously reported localities.