• Parasites, Hosts and Diseases
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• 제59권5호
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• pp.489-496
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• 2021

Ticks can transmit pathogenic bacteria, protozoa, and viruses to humans and animals. In this study, we investigated the microbiomes of Haemaphysalis longicornis according to sex and life stages. The Shannon index was significantly higher for nymphs than adult ticks. Principal coordinates analysis showed that the microbiome composition of female adult and male adult ticks were different. Notably, Coxiella-like bacterium (AB001519), known as a tick symbiont, was found in all nymphs and female adult ticks, but only one out of 4 male adult ticks had Coxiella-like bacterium (AB001519). In addition, Rickettsia rickettsii, Coxiella burnetii, and Anaplasma bovis were detected in this study.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 1997년도 제20회 화학물질의 환경독성과 건강영향
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• pp.47-71
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• 1997

• Parasites, Hosts and Diseases
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• 제48권4호
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• pp.351-353
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• 2010

To investigate the population densities of potential malaria vectors, Anopheles species were collected by light traps in malaria endemic areas, Paju and Gimpo, Gyeonggi-do of Korea. Five Anopheles Hyrcanus sibling species (An. sinensis, An. pullus, An. lesteri, An. kleini, and An. belenrae) were identified by PCR. The predominant species, An. pullus was collected during the late spring and mid-summer, while higher population consists of An. sinensis were collected from late summer to early autumn. These 2 species accounted for 92.1 % of all Anopheles mosquitoes collected, while the other 3 species accounted for 7.9%. Taking into account of these population densities, late seasonal prevalence, and long-term incubation period (9-13 months) of the Korean Plasmodium vivax strain, An. sinensis s.s is thought to play an important role in the transmission of vivax malaria in the study areas.

• 한국환경농학회지
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• 제38권3호
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• pp.139-144
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• 2019

BACKGROUND: Epigeic arthropods participate in ecological functions as predators, decomposers and herbivores. The purpose of this study was to investigate the responses of some dominant arthropods in rice fields to different forms of agricultural land management. METHODS AND RESULTS: The abundance of microarthropods was compared between rice fields and uplands in the non-growing season. Collembola, Oribatida and Mesostigmata were more abundant in the upland fields than in the paddy fields. The community composition and diversity of epigeic arthropods were compared between fallow and rice fields. The total abundance and species richness of spiders and ground beetles were not significantly different in the two types of agricultural fields. The abundance of Arctosa kwangreungensis was greater in fallow fields than in cultivated fields. The community structure of arthropods was compared between paddy fields with and without barley. The cropping system altered the community composition of spiders but not their biodiversity. Barley cultivation increased the abundance of ground beetles but decreased that of spiders. We suggest that this contrast was partly due to the availability of plants that provided shelter and food for ground beetles. CONCLUSION: These results show that soil use intensity and cropping system alter the community composition of epigeic spiders and ground beetles. This could result in ecosystem-level alterations with respect to the control of pests and weeds. Our results also suggest that biodiversity of ground-dwelling arthropods may not increase during short fallow periods.

• Parasites, Hosts and Diseases
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• 제58권5호
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• pp.537-542
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• 2020

Cockroaches inhabit various habitats, which will influence their microbiome. Although the microbiome can be influenced by the diet and environmental factors, it can also differ between species. Therefore, we conducted 16S rDNA-targeted high-throughput sequencing to evaluate the overall bacterial composition of the microbiomes of 3 cockroach species, Periplaneta americana, P. japonica, and P. fuliginosa, raised in laboratory for several generations under the same conditions. The experiments were conducted using male adult cockroaches. The number of operational taxonomic units (OTUs) was not significantly different among the 3 species. With regard to the Shannon and Pielou indexes, higher microbiome values were noted in P. americana than in P. japonica and P. fuliginosa. Microbiome composition was also evaluated, with endosymbionts accounting for over half of all OTUs in P. japonica and P. fuliginosa. Beta diversity analysis further showed that P. japonica and P. fuliginosa had similar microbiome composition, which differed from that of P. americana. However, we also identified that P. japonica and P. fuliginosa host distinct OTUs. Thus, although microbiome compositions may vary based on multiple conditions, it is possible to identify distinct microbiome compositions among different Periplaneta cockroach species, even when the individuals are reared under the same conditions.

• Parasites, Hosts and Diseases
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• 제61권1호
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• pp.60-71
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• 2023

Cockroaches can cause allergic sensitization in humans via contact with their feces or frass. Antibiotics can affect concentration of major allergen and total bacteria production in German cockroaches (Blattella germanica). This study examined the ability of antibiotic-treated German cockroaches to induce allergic airway inflammation and the effect of antibiotics on their lipopolysaccharide and Bla g1, 2, and 5 expression levels. Specifically, we measured the ability of German cockroach extract (with or without prior antibiotic exposure) to induce allergic inflammation in human bronchial epithelial cells and a mouse model of asthma. Bacterial 16S rRNA and lipopolysaccharide levels were lower in ampicillin-treated cockroaches than in the control group. The Bla g1, Bla g2, and Bla g5 expression in ampicillin-treated cockroaches decreased at both the protein and RNA levels. In human bronchial epithelial cell lines BEAS-2B exposed to the ampicillin-treated extract, expression levels of interleukin-6 and interleukin-8 were lower than that in the control group. The total cell count and eosinophil count in bronchoalveolar lavage fluid was also lower in mice exposed to the ampicillin-treated extract than in those exposed to normal cockroach extract. Mouse lung histopathology showed reduced immune cell infiltration and mucus production in the ampicillin group. Our results showed that ampicillin treatment reduced the symbiont bacterial population and major allergen levels in German cockroaches, leading to reduced airway inflammation in mice. These results can facilitate the preparation of protein extracts for immunotherapy or diagnostics applications.

• Animal Systematics, Evolution and Diversity
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• 제26권3호
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• pp.203-216
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• 2010

Adult chironomids were collected at Dangsan-ri, Muju-eup, Muju-gun, Jeollabuk-do on 5 September 2008, 22 May 2009 and 28 August 2009. A total of 221 specimens belong to the genus Polypedilum Kieffer from 1,113 adult midges collected were morphologically examined, and 16 Polypedilum species were identified. One species is new (Polypedilum dangsanensis Ree et Jeong sp. nov.) and eight species are newly recorded in Korea (P. asakawasense, P. convictum, P. decematogutatus, P. japonicum, P. kamotertium, P. pullum, P. serugense, and P. unifascium). These nine species are described with illustrations. Polypedilum nubifer was the most frequently collected species, consisting of 25.8% of the Polypedilum samples.

• Parasites, Hosts and Diseases
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• 제59권1호
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• pp.61-65
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• 2021

Diarrheal disease is the second leading cause of mortality and morbidity in children under 5 years old worldwide, and is the most common cause of malnutrition in sub-Saharan Africa. In Rwanda, diarrhea is the third leading cause of death in children under 5 years old. This study examined the association between sociodemographic factors and diarrhea in children under 5 years using the data of 7,474 households in the 2014-2015 Rwanda Demographic and Health Survey. Overall prevalence of diarrhea in this study was 12.7% in children. An increased risk for diarrhea was found for children aged 12-23 months (odds ratio (OR)=4.514), those with a low economic status (OR=1.64), those from the Western province (OR=1.439), those with poorly-educated mothers (OR=5.163), and those with families engaged in agricultural activities (OR=1.624). In conclusion, sociodemographic factors significantly affect the risk of developing diarrhea in children under 5 years in Rwanda. Designing and implementing health education promoting awareness of early interventions and rotavirus vaccination are essential to reduce diarrheal diseases for the Rwandan community.

• 한국응용곤충학회지
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• 제36권3호
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• pp.231-236
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• 1997

경북지역 동계 사과원의 절지동물상을 조사한 결과 사과나무 유인밴드 내에서는 3강 19목 58과가 채집, 분류.동정되었고, 그중 점박이응애(Tetranychus urticae Koch) 53%, 사과면충(Eriosoma lanigerum Hausmann) 16.7%, 은기문목(날개응애류) 13.3%, 톡토기목(Collembola) 9.3%순으로 나타나 초식자가 가장 많았고, 다음이 부식자였으며 천적은 드물게 조사되었다. 사과나무 낙엽에서는 2강 12목 17과가 조사되었는데, 그중 점박이응애가 63.1%로 우점이었고, 톡토기목이 13.7%였으며, 기타 절지동물은 몇 개체씩만 조사되었다. 사과나무 아래 토양에서는 2강 9목 18과가 조사되었는데, 톡토기목이 37.9%, 날개응애류가 34.4%, 점박이응애가 16.1% 순으로 나타나 부식자가 가장 많았으며, 다음이 초식자였고 천적류는 몇 개체씩만이 조사되었다.

• Parasites, Hosts and Diseases
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• 제46권4호
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• pp.243-246
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• 2008

Bla g 2 is a cockroach allergen of great importance, This study was conducted to identify IgE-binding epitope(s) of Bla g 2 using the recombinant protein technique, Approximately 50% of tested sera showed IgE reactivity to Pichia-expressed Bla g 2 (PrBla g 2) and E. coli-expressed Bla g 2 (ErBla g 2), Only 5,3% of serum samples showed stronger reactivity to PrBla g 2 than ErBla g 2, indicating that serum was reactive to conformational or carbohydrate epitopes. The full-length and 5 peptide fragments of Bla g 2 were produced in E. coli. All fragments showed IgE-binding activity to the cockroach-allergy patients' sera. Specifically, peptide fragments of amino acid residue 1-75 and 146-225 appeared to be important for IgE-binding. The information about the IgE-binding epitope of Bla g 2 can aid in the diagnosis and treatment for cockroach allergies.