The insecticidal activities of materialsderived from Dryopteris crassirhizoma Nakai against third instar larvae of three species mosquitoes (Culex pipiens, Aedes albopictus and Anopheles sinnensis) were evaluated using a direct contact mortality bioassay. The methanol extracts of D. crassirhizoma showed 100%, 87.8% and 100% larvicidal activity at 1,000 ppm against Cx. pipiens, Ae. albopictus and An. sinensis, respectively. Hexane fraction showed 100% larvicidal activity three species mosquitoes at 500 ppm after 24 hrs. Purification of the biologically active constituents from the hexane extraction with larvicidal activity was done using silica gel column chromatography. H1 and H3 fractions gave 100% mortality to Cx. pipiens, Ae. albopictus and An. sinensis at 100 ppm. H1 fraction separated with methanol to give a H111 through centrifugation. Fraction of the biologically active constituents from the H3 fraction with larvicidal activity was done using methanol. H31 fraction was determined 100% mortality to Cx. Pipiens, Ae. albopictus and An. sinensis at 50 ppm, respectively. Two fractions were analyzed C14H22O (H111, MW206.0) and C11H14O4 (H31, MW210.08) by GC and GC-MS. D. crassirhizoma derived compounds described herein could be useful for managing filed populations as larvicide of Cx. pipiens, Ae. albopictus and An. sinensis.

Temperature and insecticide are two important factors that affect survival, reproduction and other physiological processes of insects. To determine interactions of temperature and insecticide treatment on susceptible (S) and imidacloprid-resistant strains (IMI-R) of Aphis gossypii, adults were exposed to three temperatures (17, 22, and 28℃) or combinations of three temperatures (17, 22 and 28℃) and imidacloprid (LC20), and the expression of several genes (heat shock protein 70, cuticle protein, cytochrome P450, and elongation factor) were analyzed. The expression level at 17℃ of heat shock protein 70, cuticle protein, and elongation factor in S strain were up-regulated with increased time and higher than those of IMI-R strain. However, expression of cytochrome P450 was not affected by elevated temperature both S and IMI-R strain. Combined treatment of elevated temperature and imidacloprid were significantly up-regulated only cuticle protein in S strain and higher than those of IMI-R strain.

This study compared the development, reproduction, and DNA damage in insecticide (acequinocyl, bifenazate, and etoxazole)-resistant (AR, BR, and ER) and -susceptible (S) strains of Tetranychus urticae by electron beam irradiation. When eggs were irradiated with 150 Gy, the egg hatching was completely inhibited in all strains. When nymphs were irradiated, their emergence rate was decreased with increasing doses of electron beam irradiation. When adults were irradiated, the longevity and the number of eggs was not affected at all target dose in all strains. However, hatchability of F1 generation was perfectly inhibited at 400 Gy in all strains. The DNA damage caused by electron beam irradiation was evaluated by an alkaline comet assay. These results suggest that electron beam irradiation induced abnormal development and reproduction in S, AR, BR, and ER strains of T. urticae.

The two spotted mite, Tetranychus urticae Koch, is a global pest, and has developed severe resistance to several types of acaricides. Acequinocyl-resistant strain and bifenazate-resistant strain of T. urticae showed higher relative activity level of glutathion-S-transferases (GSTs) than susceptible strain. Studies of resistance in T. urticae have focused on classical detoxifying enzyme system, such as GSTs. We examined the expression of six GSTs genes in T. urticae belong to five different cytosolic classes, including two in delta, one in omega, one in mu, one in zeta, and one mitochondrial GSTs class, kappa. RT-qPCR results showed that, among these six GSTs genes, the relative expression level of delta 1 was significantly higher in bifenazate-resistant strain than in other strains (susceptible, abamectin, acequinocyl, etoxazole and pyridaben strain). Expression level of the delta 2 was also higher in acequinocyl-resistant strain than in other strains. The elevated GSTs gene transcripts following exposure to acequinocyl, bifenazate might be one of the mechanisms involved in detoxification of these acaricide. These results may be caused by different mechanisms in the resistance development of T. urticae to these two different types of acaricides.

The larvicidal and repellent activities of 33 plant extracts against two mosquitoes as Culex pipiens and Aedes albopictus were examined using direct contact application for larva and a patch test for adult. Chrysanthemum zawadskii var. alpinum, Cnidium officinale, Ginkgo biloba, Magnolia kobus, and Magnolia denudate at 1,000 ppm caused 100% mortality to Cx. pipiens larva within 24 hr. Ailanthus altissima, Dryopteris crassirhizoma, Houttuynia cordata, Mentha arvensis, Phyllostachys nigra, and Parthenocissus tricuspidata showed over 90% mortality to Cx. pipiens. C. zawadskii var. alpinum, C. officinale, G. biloba, M. kobus, M. denudate, and P. nigra gave 100% mortality at 1,000 ppm to Ae. albopictus. Acorus gramineus, Campanula takesimana, and D. crassirhizoma, showed 97.8%, 94.5%, and 94.4% mortality to Ae. albopictus at 24 hr, respectively. Five plant extracts (C. zawadskii var. alpinum, C. officinale, G. biloba, M. kobus, and M. denudate) showed 100% mortality both Cx. pipiens and Ae. albopictus. However, A. altissima gave 90% larvicidal activity to Cx. pipiens, whereas 7.8% mortality to Ae. albopictus. Several plant extracts which have highly larvicidal activities, were determined repellency against two mosquitoes species.

The insecticidal activities of materials derived from the rhizomes of turmeric, Curcuma longa L., against third instar larva of Culex pipiens and Aedes albopictus were evaluated using a direct contact mortality bioassay. Curcuma longa L. hexane extraction showed 100% larvicidal activity both two mosquitoes species at 1,000 ppm after treated 24 h. Purification of the biologically active constituents from the hexane extraction with larvicidal activity was done using silica gel column chromatography. H1 fraction gave 100% mortality to C. pipiens and A. albopictus at 100 ppm. H12 fraction was determined 100% and 87.8% larvicidal activity to C. pipiens and A. albopictus at 50 ppm, respectively. H12 fraction was analyzed as the sesquiterpene, ar-turmerone (C15H20O) and turmerone(C15H22O) by GC and GC-MS.

The fumigant activity of phosphine (PH3) and ethyl formate (EF) was determined to all stage of Phthorimaea operculella (Zeller) under high oxygen concentration (50% and 80%). Oxygenated PH3 and EF were tested at two different temperatures (20°C and 4°C) during 7 days. Two oxygenated fumigants were treated with LC10, 30 and 50 values of single fumigant against each stage of P. operculella. At 10% inhibition of hatchability concentration value, inhibition of hatchability of P. operculella eggs was shown 20.3% and 9.2% with 50% and 80% oxygenated PH3 at 20°C at 1 day after treatment, respectively. The fumigant activity of oxygenated PH3 was increased at all stage of P. operculella except eggs both 20°C and 4°C. However, oxygenated EF was determined low fumigant efficacy to hatchability of eggs and emergence rate of pupae. The insecticidal activities of P. operculella larvae and adults were slightly increased mortality rather than single EF. In this result suggests that oxygenated phosphine is effective method for managing P. operculella. But, oxygenated EF is not effective.

In this study, we investigated the effects of X-ray irradiation to control six important insect pests of floriculture crops: Liriomyza trifolii, Spodoptera litura, Myzus persicae, Tetranychus urticae, Bemisia tabaci, and Frankliniella intonsa. We irradiated on six insect pests that were placed in different positions (top, middle, and bottom) of export flower boxes after filling the boxes with roses and chrysanthemums, respectively. When irradiated with X-ray of 150 Gy, the eggs of T. urticae, B. tabaci, F. intonsa, L. trifolii, and S. litura were prevented from hatching at every position in the boxes. The pupation and emergence of L. trifolii larvae and S. litura larvae and B. tabaci nymphs and F. intonsa nymphs were inhibited at every position in the boxes. However, the emergence of T. urticae and M. persicae nymphs was not inhibited, even at the top position in the boxes. When pupae were irradiated, the emergence of L. trifolii was inhibited at every position in the boxes, while S. litura was not inhibited completely, even at the top position in the boxes. When adult T. urticae, S. litura, and L. trifolii were irradiated, the hatching rate of the F1 generation was not completely inhibited at every position. The insect pests that were not inhibited completely at the dose of 150 Gy showed much higher inhibitory effects at the dose of 250 Gy. Therefore, the dose of X-ray irradiation required to inhibit may vary according to the types of flowers and insect pests and according to their positions within the boxes.

Three insect pest, Myzus persicae, Tetranychus urticae, and Liriomyza trifolii were irradiated with electron beam (50-250 Gy) or X-ray (10-150 Gy). Longevity, egg hatching, emergence and fecundity of the test insects were measured. When irradiated to the M. persicae, emergence of nymphs did not show any differences, but fecundity was inhibited at 100 Gy (electron beam) or 30 Gy (X-ray). When irradiated to the T. urticae, egg hatching was completely inhibited at 150 Gy (electron beam) or 50 Gy (X-ray) and egg hatching of F1 generation was decreased at 150 Gy of electron beam or 50 Gy of X-ray. When irradiated to the L. trifolii, egg hatching was completely inhibited at 30 Gy of X-ray, however, electron beam irradiation was not inhibited even at 200 Gy. Egg hatching from irradiated adults was completely inhibited at 150 Gy of electron beam and X-ray. These results indicate that electron beam and X-ray irradiation induced abnormal development and reproduction, however, the dose of irradiation required to inhibit may vary according to the types of insect pests.

The effects of X-ray irradiation on development and reproduction of Spodoptera litura were examined. Eggs, larvae, pupae, and adults were irradiated at target doses of 10 - 250 Gy. When eggs were irradiated with 30 Gy, egg hatching was completely inhibited. When irradiated to the larvae, pupation was inhibited at 100 Gy and larval period was delayed. When irradiated to the pupae, emergence was inhibited at over 100 Gy. When irradiated to the adults, longevity and fecundity did not show any differences. However, egg hatching was significantly decreased at 70 Gy and above. Also, X-ray irradiation was not induced the rapid death of S. litura. Reciprocal crosses between irradiated and unirradiated moths demonstrated that males were more radiotolerant than females. The levels of DNA damage in S. litura adults were evaluated using the alkaline comet assay. Our results indicate that X-ray irradiation increased levels of DNA damage. The recovery of DNA damage in S. litura adults increased as time passed. But DNA damage hasn't recovered fully. These results indicate that X-ray irradiation induced abnormal development and reproduction by DNA damage in S. litura.

The effect of electron beam irradiation on development and reproduction of susceptible strain (S) and imidacloprid-resistance strain (IMI-R) of Aphis gossypii were compared. Nymphs and adults of S and IMI-R strain were irradiated at target doses of 50, 100, 150, and 200 Gy. When nymphs were irradiated, emergence rate was not affected at all target dose, but number of F1 nymphs was perfectly inhibited at 150 Gy in both strains when irradiated to the adults, longevity slightly decrease at 150 Gy and above. Fecundity was strongly decreased at 100 Gy, but was not completely inhibited even at 200 Gy. Emergence rate of F1 nymph was decreased at 100 Gy and completely inhibited at 200 Gy. However, there was no significant differences on development and reproduction of S and IMI-R strain. We also conducted the comet assay immediately after irradiation and over the following 7 day periods. In addition, we performed quantitative real-time PCR on several genes.

Wood boring insects are the major problem of many industries, such as hardwood brokers, importers, merchants, and manufacturers of furniture. Phosphine (PH3) is highly toxic to insects and is known to penetrate treated material. In this study, effectiveness of PH3 which is altered methyl bromide, was examined with Monochamus saltuaris, Platypus koryoensis, Cryphalus fulvus, and Xyleborus mutilatus. Fumigation to M. saltuaris, P. koryoensis, C. fulvus, and X. mutilatus was carried in a desiccator (12L) at 20℃ for 24 h. As a result, LC99 of PH3 to M. saltuaris, P. koryoensis, C. fulvus, and X. mutilatus was showed 0.455 mg L-1, 0.804 mg L-1, 0.243 mg L-1 and 0.046 mg L-1 in a desiccator(12L) at 20℃, respectively. M. saltuaris, P. koryoensis, C. fulvus, and X. mutilatus 100 % mortality was showed in a fumigation chamber (10 m3 and 100 m3) at normal temperature. In these results indicates that PH3 described could be useful for fumigant agent of 4 species wood pests.

The potato tuber moth, Phthorimaea operculella (Zeller), is considered one of the main causes of potato losses during harvesting and storage. The pest occur throughout the year and its larvae damage the leaves, twigs and tubers. In this study, we have investigated the effects of ethyl formate (EF) and phosphine (PH3) against P. operculella. Fumigation to all stage of P. operculella was carried in a desiccator system at 5℃ and 20℃ for 24 h. As a result, LC99 of PH3 to all stage of P. operculella was showed 1.953 mg L-1 (eggs), 0.100 mg L-1 (larvae), 4.884 mg L-1 (pupae) and 0.240 mg L-1 (adults) at 20℃, respectively. LC99 of EF to all stage of P. operculella was observed 19.808 mg L-1 (eggs), 6.783 mg L-1 (larvae), 141.476 mg L-1 (pupae) and 3.223 mg L-1 (adults), at 20℃ respectively. Larvae and adults showed the highest susceptibility to PH3 and EF at 20℃. LC99 of PH3 to all stage of P. operculella was showed > 1.5 mg L-1 (eggs), 0.187 mg L-1 (larvae), > 1.5 mg L-1 (pupae) and 0.386 mg L-1 (adults) at 5℃ , respectively. LC99 of EF to all stage of P. operculella was showed 27.479 mg L-1 (eggs), 9.580 mg L-1 (larvae), 55.759 mg L-1 (pupae) and 3.084 mg L-1 (adults) at 5℃, respectively. These results indicated that the fumigant efficiency of PH3 and EF is more effective with treated in room temperatures against termites.

The Japanese termite, Reticulitermes speratus Kolbe, is distributed in Korea widely. Although, termites are not currently a great problem in Korea, it might be increased commercial losses from imported timber. Phosphine (PH3) is very effective fumigant and is widely used to control pests. Oxygen treatment was found to enhance phosphine toxicity and reduce fumigation time against various life stage of insects. In this study, we determined efficacy of oxygenated phosphine fumigation for controlling R. speratus. Fumigation to adults of R. speratus was carried in a desiccator system at 20.9% (normal), 50% and 80% of oxygen concentration for 24 h. Fumigations under higher oxygen levels greatly increased phosphine toxicity to R. speratus. Mortality of termite was increased 15.0% and 16.2% in the 50.0% and 80.0% oxygen concentration with 0.25 mg L-1 phosphine at 5℃, respectively. 100% mortality was determined in 80.0% oxygen concentration with 0.5 mg L-1 phosphine at 5℃. Oxygenated phosphine fumigations have marked potential to improve insecticidal efficacy against R. speratus. These results merit further study as potential fumigant for control of wood destroying pests.

This study was examined for activity of aggregation pheromone trap with residual effect of insecticides against Riptortus pedestris. Time of escape was from aggregation pheromone trap researched 49.74 min (ET99) and 65.01 min (ET99) with 1st and 2nd instar nymph respectively. Six insecticides for the stink bugs were treated to 3 different materials (wood, metal, and plastic). Bifenthrin and fenitrothion were showed 100% insecticidal activity at 48 h to all developmental stage of R. pedestris. Residual effect of bifenthrin and fenitrothion on plastic material were showed 100% insecticidal activity over 15 day after treatment with 1st, 3rd instar nymphs, and adults except 5th instars nymph. In field test using plastic material trap with two pesticides, 1st instar nymphs and adults were showed 100% mortality until 10 day after treatment. These results indicate that R. pedestris might be managed using aggregation pheromone trap with insecticides.

Monochamus saltuarius, which mediates Bursaphelenchus xylophilus is one of the important vector of pine wilt disease recently. M. saltuarius showed difference with weight, growth, and oviposition according to species of trees. The most feeding amount and feeding area were determined in P. koraiensis. However, M. saltuarius almost did not feed and longevity was observed very short time only for 10 day in Sciadopitys verticillata. Weight, length and head width were measured the highest growth of M. saltuarius in P. koraiensis. Female of M. saltuarius was determined more growing than male of M. saltuarius in all species of trees. Tree preference for oviposition of M. saltuarius was the highest choice in P. densiflora. However, lots of scar for oviposition have observed but M. saltuarius laid less eggs in P. rigida. This result is related to bark thickness of trees. Ovipositional frequency has been consistently maintained to P. densiflora and P. koraiensis at 20 day intervals. In this study, physiological and ecological characteristic of M. saltuarius to preference of trees were researched could be helpful for managing of M. saltuarius.

MicroRNAs (miRNAs, miRs) are about 21-25 nucleotides in length and regulate mRNA translation by base pairing to partially complementary sites, predominantly in the 3’-untranslated region (3’-UTR) of the target mRNA. In this study, the expression profile of miRNAs was compared and analyzed for the establishment of miRNA-related odontoblast differentiation using MDPC-23 cells derived from mouse dental papilla cells. To determine the expression profile of miRNAs during the differentiation of MDPC-23 cells, we employed miRNA microarray analysis, quantitative real-time PCR (qRT-PCR) and Alizaline red-S staining. In the miRNA microarray analysis, 11 miRNAs were found to be up- or down-regulated more than 3-fold between day 0 (control) and day 5 of MDPC-23 cell differentiation among the 1,769 miRNAs examined. In qRT-PCR analysis, the expression levels of two of these molecules, miR-194 and miR-126, were increased and decreased in the control MDPC-23 cells compared with the MDPC-23 cells at day 5 of differentiation, respectively. Importantly, the overexpression of miR-194 significantly accelerated mineralization compared with the control cultures during the differentiation of MDPC-23 cells. These results suggest that the miR-194 augments MDPC-23 cell differentiation, and potently accelerates the mineralization process. Moreover, these in vitro results show that different miRNAs are deregulated during the differentiation of MDPC-23 cells, suggesting the involvement of these genes in the differentiation and mineralization of odontoblasts.

Cytokines are known to function as regulatory molecules that can be produced by virtually every nucleated cell type in the body, including lymphocytes, monocytes/macrophages, epithelial cells, fibroblasts, and many others. Cytokines include lymphocyte-derived factors (lymphokines), monocyte-derived factors (monokines), hematopoietic factors (colony-stimulating factors), connective tissue/ growth factors, and chemotactic chemokines. Cytokines released in response to infection can affect tumor development in different ways. When exposed to infectious agents, cytokines are secreted by sentinel cells, such as macrophages and dendritic cells. These cytokines include interleukin 1 (IL-1) and tumor necrosis factor-α, as well as others, such as IL-6, IL-12, and IL-18. When released in sufficient quantities, these molecules can cause inflammation. Chronic inflammation is highly associated with tumor initiation, promotion, and progression. In this article, we review the roles and mechanisms of cytokines in tumor development.

Malignant tumor cells outgrow new blood vessel formation and tend to be in hypoxic state. Hypoxic cancer cells adapt to hypoxic conditions by transforming its characteristics. On the other hand, one of the most important features of cancer cells is that carcinoma cells loses its inherent epithelial phenotype and acquires mesenchymal characteristics, called as epithelial-mesenchymal transition(EMT). It has been already well known that EMT contributes to tumor invasion and metastasis. The present study investigated whether hypoxia play a major role in induction of phenotypic changes of oral squamous cell carcinoma(OSCC). Furthermore, the mechanism of EMT in oral squamous cell carcinoma cells by hypoxia has been clarified. To mimic hypoxic condition, cobalt chloride and desferoxamine, well-known hypoxic mimetic agents, were used. This study shows that hypoxia suppresses the expression of E-cadherin(epithelial marker) and increases vimentin and N-cadherin( mesenchymal markers) in OSCC. In addition, α5 integrin protein, which is a receptor for fibronectin and an important molecule for tumor invasion, is prominently induced by hypoxia.

The toxicity of perilla-chinese Basil, Perilla frutescens whole plant-derived materials to third-instar of larva Plutella xylostella was examined using that of four insecticides and 5 constituents of P. frutescens from other research materials. The active principle of P. frutescens was identified as the sesquiterpenoids α-farnesene by spectroscopic analysis. In leaf-dipping bioassay, α-farnesene (LD50, 36.9) was 3.9 times more toxic than β-farnesene (LD50, 145.2) against P. xylostella larva, based on 48h LD50 values. This compound was less toxic than insecticides. Naturally occurring α-farnesene merit further study as potential diamond back moth control agent.