• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.63-67
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• 2014

This paper describes a new species of chigger mite (Acari: Trombiculidae), Gahrliepia cangshanensis n. sp., from rodents in southwest China. The specimens were collected from Yunnan red-backed voles, Eothenomys miletus (Thomas, 1914), and a Chinese white-bellied rat, Niviventer confucianus (Milne-Edwards, 1871) in Yunnan Province. The new species is unique mainly in its number of dorsal setae (n=21), and it has the following features: fT (formula of palpotarsus)=4B (B=branched), fp (formula of palpal seta)=B/N/N/N/B (N=naked), a broad tongue-shaped scutum with an almost straight posterior margin, and 17 PPLs (posterior posterolateral seta) with a length of 36-43 ${\mu}m$. This chigger mite may also infect other rodent hosts and may be distributed in other localities.

• Korean Journal of Veterinary Service
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• v.33 no.2
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• pp.167-171
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• 2010

Majority of asthma and atopic dermatitis are known to be spontaneously sensitive to house dust mite allergen. Control of house dust mite populations has been principally achieved by using chemical insecticides. But the risk to human health would be a potential problem. Moreover, house dust mite remain as allergens even after death. So, It is more effective method keeping the house dust mites away than killing them. The use of plant-derived repellents has been considered as a promising alternative to chemical repellents. Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. It has insect repellent properties and is an active ingredient in some commercial mosquito repellents. These studies were carried out to investigate repellent effects of Eucalyptus oil against house dust mites and compare lemongrass oil. Eucalyptus oil and lemongrass oil were exposed at different doses (0.2, 0.1, 0.05, 0.025, 0.0125, $0.00625{\mu}l/cm^2$) and different times (1, 3, 6 hours) on house dust mites. The most effective dose of Eucalyptus and lemongrass oils against house dust mites was $0.1{\mu}l/cm^2$ and $0.025{\mu}l/cm^2$. Each repellent effect(%) in most effective dose was 90.3% (Eucalyptus) and 80.8% (lemongrass).

• Parasites, Hosts and Diseases
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• v.59 no.3
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• pp.319-324
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• 2021

Incidence of tsutsugamushi disease (scrub typhus) caused by Orientia tsutsugamushi, is steadily increasing. It is a mite-borne disease transmitted by chigger mites. In this study, the chigger mites were collected from field small mammals in Hwaseong-si (city), Gyeonggi-do (province), Korea, 2019 and 2020. The field small mammals captured were 56 Apodemus agrarius (94.9%) and 3 Crocidura lasiura (5.1%). A total of 7,531 chigger mites were collected from the captured small mammals. Using PCR test, 153 chigger mite pools were examined and 17 pools were reported positive for O. tsutsugamushi. The O. tsutsugamushi were identified to 5 strains; Jecheon strain was most prevalent, followed by Boryong strain. The other strains were OI011, Taguchi, and Shimokoshi. Collectively, these results provide essential regional information on mite-borne tsutsugamushi disease in the Hwaseong-si, and further contribute to bring awareness and rapid diagnosis for the tsutsugamushi disease.

• The Journal of the Korea Contents Association
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• v.20 no.4
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• pp.454-463
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• 2020

The purpose of this study is to check the antimicrobial activity of terpene, a natural product-derived extract against bedding bacteria, and compare the number of bacteria detected. To this end, the number of mites and microbiological surveys were conducted on the pillows used at home to identify the presence of pathogenic strains that could cause the disease. Also, after two weeks test using pillow with terpene, a natural origin extract, the rate of reduction of fungi before and after the use of the substance and the effect of eradicating mites were evaluated. The antimicrobial activity of the terpene was observed by using the Pour plate method. The anti-mite effect was detected as weak positive (less than 100) in 2 of 4 pillows in the first test without the use of terpene. In the second experiment using a terpene, all were confirmed to be reduced to negative less than 20. The best anti-mite efficacy of terpene was found to be 20%. The purpose of this study is to suggest the possibility of developing antibacterial and anti-mite spray products for bedding using terpene.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.1
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• pp.58-62
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• 2017

The two-spotted spider mite (Tetranychus urticae) has sustained damage on more than 200 host plants worldwide. Many farmers have relied on chemical acaricides to control mite, but the abuse of acaricides has caused serious resistance to mite. To overcome this problem, microbial control using entomopathogenic fungi have been studied. Entomopathogenic fungi have been an important role against the control of pest, and most of their culture products have been demonstrated to have virulence against pest population. In this study, we evaluated and compared the virulence of culture filtrates, aerial conidia and blastospores of selected Metarhizium anisopliae 4-2 and Beauveria bassiana 2R-3-3-1, respectively, among two-spotted spider mite-pathogenic fungi. As a result, the virulence was confirmed in all treatments, and the accumulated mortality rates were between 77 and 100% within 7 days. Especially, treatment with the fungal culture filtrate alone exhibited quite high virulence, and combined treatment with aerial conidia or blastospores enhanced activity. However, the median lethal time of treatments was not significantly different. When two isolates were compared, M. anisopliae 4-2 showed higher virulence than B. bassiana 2R-3-3-1. These results suggest that the selected two fungal isolates and their culture products could be used effectively for the control of two-spotted spider mite.

• Korean journal of applied entomology
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• v.37 no.1
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• pp.81-89
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• 1998

In a survey on the pests of stored garlic, an unrecorded gall mite in Korea was found to damage on garlic surface making stripe feeding injuries. The mite was identified as Aceria tulipae (Keifer) 1938, based on the morphological characteristics. Light microscopic and SEM observations on garlics fed by A. tulipae revealed that there was no gall formation by feeding but there was only surface damage symptom. The damaged garlic surface showed symptom of losing gloss in the early stage and the feeding traces under dissecting microscope. Brown stripes appeared in the middle stage of damage and the whole scale turned to dark brown and shrank in the later stage. When the mite infested garlics were fumigated with 3 g/m3 aluminium phosphide for 72 hours in airtight plastic boxes (1 m x 1 m x 1 m), the mortalities of mite were over 90% for Namdo garlics.

• Weed & Turfgrass Science
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• v.3 no.2
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• pp.114-120
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• 2014

Turfgrass insect pests were investigated in different turf sod production areas of Korea. Twelve insect pest species of 7 families in 6 orders and one Eriophyidae mite, Aceria zoysiae were collected from turf sod production areas. The zoysiagrass mite was most frequently occurred zoysiagrass sod production areas. Damaged rate by zoysiagrass mite was increased from May to September. Noctuidae (Spodoptera depravata, Agrotis ipsilon and A. segetum) and Pyralidae (Crambus sp.) insect pests in Lepidoptera were attracted in A. ipsilon sex pheromone trap. Eggs and larva of A. ipsilon was the highest occurred August. Zoysiagrass mite and A. ipsilon were main insect pests in turf sod production areas in Korea.

• Biomedical Science Letters
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• v.19 no.4
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• pp.344-347
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• 2013

The S100A8 and S100A9 proteins play important roles in inflammatory diseases. The house dust mite acts as a major allergen that induces allergic diseases. We investigated the effect of the house dust mite on S100A8 and S100A9 protein expression in monocytes. We also examined the effect of CCL2, a powerful monocyte chemoattractant, on the expression of both proteins. Extract of Dermatophagoides pteronissinus (DP), recombinant Der p 1 and Der p 2, or CCL2 had no effect on S100A8 and S100A9 expression in human monocytic THP-1 cells. Monocytes were isolated from healthy donors and treated with DP, Der p 1, and Der p 2. S100A8 expression in monocytes increased after a 24 h stimulation with DP, Der p 1, and Der p 2, and CCL2 also increased S100A8 production. However, S100A9 expression in monocytes was not altered by DP, Der p 1, Der p 2, or CCL2. These results indicate that house dust mite and CCL2 may trigger an inflammatory response by altering S100A8 expression.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.429-432
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• 2010

A mite damage was observed in spinach (Spinacia oleracea L.) under organic culture greenhouses. The mite was identified as Tyrophagus similis Volgin, 1949. It was very difficult for the farmers to diagnose the mite damage because of its tiny size about 0.5 nm in length. And the symptom was not clear at the early growth stage of the spinach because the mite mainly attack the very young leaves. In this study, we first report the spinach damages by T. similis in Korea. Informations on the mite morphology and the spinach damage symptoms are provided for the diagnosis.

• Biomedical Science Letters
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• v.22 no.4
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• pp.211-214
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• 2016

House dust mite is an essential allergen in the pathogenesis of allergic diseases. Abnormal regulation of neutrophil apoptosis is an important pathogenic process in allergic diseases. In the present study, we investigated the effects of house dust mites on spontaneous apoptosis of neutrophils and its associated mechanisms. Extract of Dermatophagoides pteronissinus (DP) inhibited neutrophil apoptosis in a time-dependent manner. Cycloheximide (CHX), an inhibitor of translation, increased apoptosis of DP-treated neutrophils as well as control cells. The pro-apoptotic effect of CHX was blocked by DP in neutrophils. In addition, DP increased the phosphorylation of Bad in a time-dependent manner, indicating that it exerted an inhibitory effect on the function of Bad. These results suggest that DP has anti-apoptotic effects of neutrophils and may regulate protein synthesis and activation of Bad. Moreover, these findings may shed light on elucidation of allergy pathogenesis due to house dust mites.