• Parasites, Hosts and Diseases
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• 제51권5호
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• pp.557-562
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• 2013

In contrast to the gradual reduction in the number of locally transmitted malaria cases in China, the number of imported malaria cases has been increasing since 2008. Here, we report a case of a 39-year-old Chinese man who acquired Plasmodium ovale wallikeri infection while staying in Ghana, West Africa for 6 months in 2012. Microscopic examinations of Giemsa-stained thin and thick blood smears indicated Plasmodium vivax infection. However, the results of rapid diagnostic tests, which were conducted 3 times, were not in agreement with P. vivax. To further check the diagnosis, standard PCR analysis of the small-subunit rRNA gene was conducted, based on which a phylogeny tree was constructed. The results of gene sequencing indicated that this malaria is a variant of P. ovale (P. ovale wallikeri). The infection in this patient was not a new infection, but a relapse of the infection from the one that he had contracted in West Africa.

• Genomics & Informatics
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• 제9권4호
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• pp.197-199
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• 2011

The biological interpretation of two-dimensional (2D) gel electrophoresis experiments is a key step toward understanding the functions of biological systems. We here present a web-based integrated database, called 2DSpotDB, for the management of proteome data derived from several pathogens. The 2DSpotDB was established as a part of the management of a pathogen proteome project at the Korea National Institute of Health. The goals of the 2DSpotDB implementation are to store and define important pathogen genes, retrieve information obtained by 2D polyacrylamide gel electrophoresis and mass spectrometry, and create an integrated system to provide pathogen proteome information for biological scientists. This database currently contains 14 gels and information on 387 protein spots, among which 329 proteins were identified and annotated.

• Parasites, Hosts and Diseases
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• 제54권4호
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• pp.407-414
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• 2016

Malaria remains a serious public health problem in Shandong Province, China; therefore, it is important to explore the characteristics of the current malaria prevalence situation in the province. In this study, data of malaria cases reported in Shandong during 2012-2014 were analyzed, and Plasmodium species were confirmed by smear microscopy and nested-PCR. A total of 374 malaria cases were reported, 80.8% of which were reported from 6 prefectures. Of all cases, P. falciparum was dominant (81.3%), followed by P. vivax (11.8%); P. ovale and P. malariae together accounted for 6.4% of cases. Notably, for the first time since 2012, no indigenous case had been reported in Shandong Province, a situation that continued through 2014. Total 95.2% of cases were imported from Africa. The ratio of male/female was 92.5:1, and 96.8% of cases occurred in people 20-54 years of age. Farmers or laborers represented 77.5% of cases. No significant trends of monthly pattern were found in the reported cases. All patients were in good condition after treatment, except for 3 who died. These results indicate that imported malaria has increased significantly since 2012 in Shandong Province, especially for P. falciparum, and there is an emergence of species diversity.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• 제18권4호
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• pp.389-397
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• 2007

This paper proposes miniaturized broadband parasitic patch antenna. The proposed antenna consists of a probe fed reduced size main patch and U-shaped parasitic patches. The parasitic patches are incorporated to the radiating edges of the main patch to miniaturize the antenna size. The broadband impedance matching can be achieved by either E-plane or H-plane electromagnetic coupling between main patch and parasitic elements. The size of radiating elements is $18{\times}17.6\;mm^2$ and the overall dimension of designed antenna with substrate and ground plane is $25{\times}30{\times}4\;mm^3$. The fabricated antenna on a FR4 substrate shows two resonant frequencies(5.12 GHz and 6.08 GHz) with 27.3 %(1.5 GHz) fractional bandwidth at 5.5 GHz center frequency. The calculated and measured radiation patterns are almost similar to conventional patch antenna.

• Parasites, Hosts and Diseases
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• 제55권1호
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• pp.55-60
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• 2017

Fascioliasis is a foodborne zoonotic parasitic disease. We report 4 cases occurring in the same family, in whom diagnosis of acute fascioliasis was established after series of tests. One case was hospitalized with fever, eosinophilia, and hepatic lesions. MRI showed hypodense changes in both liver lobes. The remaining 3 cases presented with the symptom of stomachache only. Stool analysis was positive for Fasciola eggs in 2 adult patients. The immunological test and molecular identification of eggs were confirmed at the National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China. The results of serological detection were positive in all the 4 patients. DNA sequencing of PCR products of the eggs demonstrated 100% homology with ITS and cox1 of Fasciola hepatica. The conditions of the patients were not improved by broad-spectrum anti-parasitic drugs until administration of triclabendazole.

• Parasites, Hosts and Diseases
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• 제50권4호
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• pp.379-384
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• 2012

Resistance of Plasmodium spp. to anti-malarial drugs is the primary obstacle in the fight against malaria, and molecular markers for the drug resistance have been applied as an adjunct in the surveillance of the resistance. In this study, we investigated the prevalence of mutations in pvmdr1, pvcrt-o, pvdhfr, and pvdhps genes in temperate-zone P. vivax parasites from central China. A total of 26 isolates were selected, including 8 which were previously shown to have a lower susceptibility to chloroquine in vitro. For pvmdr1, pvcrt-o, and pvdhps genes, no resistance-conferring mutations were discovered. However, a highly prevalent (69.2%), single-point mutation (S117N) was found in pvdhfr gene. In addition, tandem repeat polymorphisms existed in pvdhfr and pvdhps genes, which warranted further studies in relation to the parasite resistance to antifolate drugs. The study further suggests that P. vivax populations in central China may still be relatively susceptible to chloroquine and sulfadoxine-pyrimethamine.

• Parasites, Hosts and Diseases
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• 제58권2호
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• pp.201-204
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• 2020

Taenia saginata infection has seldom been reported in Cambodia. In this study, we performed a survey of intestinal parasites in 1,156 residents of Preah Vihear and Stung Treng Provinces in 2018. The results revealed that 26 (2.4%) cases were positive for Taenia spp. eggs. In order to obtain the strobilae of the tapeworms, 2 patients in Preah Vihear were treated with praziquantel and purged with magnesium salts. The proglottids expelled after the medication were morphologically and molecularly analyzed to determine the species. The main uterine lateral braches in gravid proglottids were > 15 in number suggesting that they are either T. saginata or Taenia asiatica. The sequences of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene and 2 nuclear loci, elongation factor-1 alpha (ef1) and ezrin-radixin-moesin-like protein (elp), were identical to the sequences of T. saginata available in GenBank but distant from Taenia solium, T. asiatica, and T. saginata-T. asiatica hybrid. This is the first report of the presence of T. saginata in the northern part of Cambodia bordering Lao PDR based on a molecular confirmation.

• Parasites, Hosts and Diseases
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• 제59권2호
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• pp.179-182
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• 2021

Human infection with Taenia asiatica or a hybrid between Taenia saginata and T. asiatica has not been reported in Cambodia. We detected for the first time a hybrid form between T. saginata and T. asiatica in Preah Vihear Province, Cambodia. An adult tapeworm specimen, i.e., 75 cm long strobila without scolex, was expelled from a 27-year-old man after praziquantel medication and purging. It was morphologically indistinguishable between T. saginata and T. asiatica. Several proglottids were molecularly analyzed to confirm the tapeworm species. The mitochondrial gene encoding cytochrome c oxidase subunit 1 (cox1) and nuclear genes encoding elongation factor-1α (ef1) and ezrin-radixin-moesin (ERM)-like protein (elp) were sequenced, and a single-allele analysis was performed to confirm the haploid genotype. The results revealed that our sample showed a discrepancy between the mitochondrial and 2 nuclear genes. It possessed homozygous sequences typical of T. saginata at cox1 and ef1 loci. However, it was heterozygous at the elp locus, with 1 allele in T. asiatica (elpA) and 1 in T. saginata (elpC), which indicates that it is a hybrid between T. saginata and T. asiatica. The present results confirmed the presence of a hybrid between T. saginata and T. asiatica in Cambodia and strongly suggest the existence of also 'pure' T. asiatica in Cambodia.

• Parasites, Hosts and Diseases
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• 제58권6호
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• pp.619-625
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• 2020

Human hookworm infections caused by adult Ancylostoma spp. and Necator americanus are one of the most important tropical diseases. We performed a survey of intestinal helminths using the Kato-Katz fecal examination technique targeting 1,156 villagers residing in 2 northern provinces (Preah Vihear and Stung Treng) of Cambodia in 2018. The results revealed a high overall egg positive rate of intestinal helminths (61.9%), and the egg positive rate of hookworms was 11.6%. Nine of the hookworm egg positive cases in Preah Vihear Province were treated with 5-10 mg/kg pyrantel pamoate followed by purging with magnesium salts, and a total of 65 adult hookworms were expelled in diarrheic stools. The adult hookworms were analyzed morphologically and molecularly to confirm the species. The morphologies of the buccal cavity and dorsal rays on the costa were observed with a light microscope, and the nucleotide sequences of mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were analyzed. The majority of the hookworm adults (90.7%) were N. americanus, whereas the remaining 9.3% were Ancylostoma ceylanicum, a rare hookworm species infecting humans. The results revealed a high prevalence of hookworm infections among people in a northern part of Cambodia, suggesting the necessity of a sustained survey combined with control measures against hookworm infections.

• Proceedings of the Optical Society of Korea Conference
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• 한국광학회 2003년도 제14회 정기총회 및 03년 동계학술발표회
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• pp.148-149
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• 2003

The parasitic effects due to the current blocking layer limit the bandwidth of the semiconductor laser diode. Thus, the parasitic response of various blocking layers was analyzed. The inin type was the best choice for the leakage current reduction and the bandwidth expansion.