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        21.
        2017.10 구독 인증기관·개인회원 무료
        Insect growth depends on temperature and nutrient. Intake nutrients activate insulin signaling pathway, which mediatesthe nutrient signal to coordinate growth in entire body. A subtropical species, Maruca vitrata (Lepidoptera: Crambidae),gives serious damages on various Fabaceae crops. This study predicted seven components (InR, IRS, PI3K, PTEN, Akt,mTOR, FOXO) of the insulin signal and showed that some of the insulin gene expression levels are highly correlatedwith developmental rates. These correlations may be applied to amend a temperature-dependent growth modeling of M.vitrata.
        24.
        2017.04 구독 인증기관·개인회원 무료
        Oriental fruit fly, Bactrocera dorsalis, is one of the serious pests of fruit throughout the world. Two regional populations (Bangladeshi and Malaysia) were collected using methyl eugenol lure and one laboratory population was obtained from Thailand. Three populations were compared in cytochrome b (CYB) cytochrome oxidase I (COI) sequences. COI sequences were highly homologous. However, CYB sequences were polymorphic and used to discriminate these regional populations by a phylogenetic analysis. In CYB phylogeny analysis, Malaysia and Thailand populations were clustered and Bangladeshi population was separated
        26.
        2016.04 구독 인증기관·개인회원 무료
        Entomopathogenic nematodes (EPNs) of the genus Steinernema are pathogenic to the insects and well known as ideal models for understanding parasite-host interaction. EPNs harbor a number of bacterial symbionts in their gut belonging to the noble genus Xenorhabdus which are capable of killing insects by themselves or by combination with nematodes by suppressing insect immune defense. Here, we report host range of Steinernema monticolum and its symbiont Xenorhabdus hominickii. S. monticolum has a diverse host range including lepidopteran and coleopteran insects although they showed higher pathogenicity to the lepidopteran insects. Especially, X. hominickii suppressed insect immune responses. A target insect, Spodoptera exigua, exhibited both cellular and humoral immune responses by expressing antimicrobial peptides and forming nodules in response to heat-killed X. hominickii. However, live bacteria significantly suppressed the immune responses. An addition of arachidonic acid to the bacterial infection significantly rescued the immune responses, suggesting eicosanoid biosynthetic pathway as a pathogenic target of X. hominickii.
        33.
        2014.04 구독 인증기관·개인회원 무료
        Teratocytes (TCs) are the cells derived from the embryonic serosal membrane of some parasitic hymenopteran insects. As a parasitic factor, TCs are multifunctional in host regulation by inducing nutritional, immune, and developmental alterations. However, little is understood about their genetic constituents. This study reveals a comprehensive view of the genes expressed by TCs through a transcriptome analysis based on RNAseq technology. More than 6.29 Gb sequences were used to assemble 34,686 contigs (>200 bp) and annotated into different functional categories. The TC transcriptome profile was clearly distinct from those of hemocytes and the fat body. The TC transcriptome contained components of insulin signaling and biosynthesis of juvenile hormone and 20-hydroxyecdysone. TCs also expressed various groups of digestive enzymes, supporting its nutritional role for the growing parasitoid larvae in parasitism. Furthermore, this transcriptome analysis annotated two kinds of immunosuppressive serine protease inhibitors (serpins) and Rho GTPase-activating proteins (RhoGAPs). To determine the biological functions of these factors, we devised ex vivo RNA interference (RNAi) by conducting knockdown of gene expression in in vitro cultured TCs followed by injection of the treated TCs to test insects. Ex vivo RNAi revealed that some serpins and RhoGAPs expressed in TCs inhibited host cellular immunity. This study reports a transcriptome of the unique TC animal cell, and its immunosuppressive genetic factors using ex vivo RNAi technology.
        34.
        2012.10 구독 인증기관·개인회원 무료
        An endoparasitoid wasp, Cotesia plutellae, parasitizes young larvae of the diamondback moth, Plutella xylostella, with its parasitic factors of polydnavirus, venom, ovarian proteins, and teratocytes (TC). TCs are originated from embryonic serosal membrane at hatch of C. plutellae eggs. TCs, after released in hemocoel of parasitized larvae, increased their average cell size from 20.6 μm to 77 μm during whole developmental period of the parasitoid larvae, but did not increase their cell number by maintaining about 150 cells per larvae. TCs of C. plutellae, are considered to be involved to extend the host larval development period and to arrest larval-pupal metamorphosis, were cultured in an insect cell culture medium for 21 days. Like TCs in parasitized larvae, in vitro cultured TCs showed increase in cell size, but did not show increase of cell number. Microinjection of in vitro cultured TCs significantly inhibited larva-to-pupa metamorphosis of nonparasitized P. xylostella, in which pupated host also showed extended larval period. Larvae injected with TCs exhibited alteration in expression of ecdysone receptor (EcR) and insulin receptor (InR) as well as in parasitized larvae. Teratocyte-secretory factors in culture medium showed this antimetamorphic effect on P. xylostella, while heat treated TC culture medium lost the effect. However, a successful parasitization of C. plutellae required both TCs and polydnavirus to alter host physiology.
        35.
        2012.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We utilize AKARI's slitless spectroscopic capability to detect the 3.3 μm polycyclic aromatic hydrocarbons (PAHs) emission and measure star formation (SF) activity for various AKARI programs. First, we obtain 2∼5μm spectra of 20 flux-limited galaxies with mixed SED classes in order to calibrate the 3.3 μm PAH luminosity (LPAH 3.3) as a star formation rate (SFR) indicator. We find that LPAH3.3 correlates with LIR as well as with the 6.2 μm PAH luminosity ( LPAH 6.2). The correlations does not depend on SED classes. We find that ULIRGs deviate from the correlation between PAH luminosities and LIR, while they do not for the correlation between PAH luminosities. We suggest possible effects to cause this deviation. On the other hand, how AGN activity is linked to SB activity is one of the most intriguing questions. While it is suggested that AGN luminosity of quasars correlates with starburst (SB) luminosity, it is still unclear how AGN activity is connected to SF activity based on host galaxy properties. We are measuring SFRs for the LQSONG sample consisting of reverberation mapped AGNs and PG-QSOs. This is an extension of the ASCSG program by which we investigated the connection between SB and AGN activities for Seyferts type 1s at z ~ 0.36. While we found no strong correlation between LPAH3.3 and AGN luminosity for these Seyferts 1s, LPAH3.3 measured from the central part of galaxies correlates with AGN luminosity, implying that SB and AGN activities are directly connected in the nuclear region.
        3,000원
        36.
        2012.05 구독 인증기관·개인회원 무료
        Teratocytes are originated from embryonic serosal membrane of some endoparasitoid wasps. Cotesia plutellae eggs release teratocytes in parasitoid host hemocoel at hatch in about 150 cells per egg. Teratocytes of C. plutellae were cultured in an insect culture medium for at least 14 days. Teratocytes cultured in vitro showed no increase in cell numbers but increased in cell size. Similarly,teratocytes in parasitized larvae did not increase cell numbers, but increased their cell size. Microinjection of invitro cultured teratocytes in to third instar larvae of nonparasitized Plutella xylostella showed a dose-dependently inhibitory effect on development and larval-pupal metamorphosis. In addition, teratocytes prolonged the immature developmental period and reduced the pupation rate, in which young aged host larvae were more sensitive to teratocytes treatment than old larvae. These results suggest that teratocytes play a crucial role in successful parasitization of C.plutellae by altering host developmental program.
        37.
        2011.10 구독 인증기관·개인회원 무료
        Cell transplantation therapy using adult stem cells has recently been identified as a potential treatment for spinal cord injury (SCI). But, recovery after traumatic SCI is very limited. As dogs are physiologically much more similar to human compared with other traditional mammalian models in disease presentation and clinical responses, a number of researches demonstrated canis familiaris is a suitable model for human diseases. This study investigated the effect of transplantation of canine Mesenchymal Stem Cells (cMSC) and neural-induced cMSC (nMSC) to understand how these cells improve neurological function in canine SCI model. The differentiation of cMSC into neural precursor cells was induced in dulbecco’s modified eagle’s medium supplemented with N2-supplement, dibutyryl cyclic adenosine monophosphate, and butylated hydroxyanisole. SCI was induced between T1 and T2 by surgical hemi-section in adult dogs, and then assigned to two groups according to the applied cell types (cMSC vs nMSC). Pelleted cMSC or nMSC were transplanted directly into the injured site after SCI, respectively. Analysis of motor function after transplantation was evaluated by modified Olby score. Magnetic resonance imaging (MRI), histological and immunohistichemical analysis were also performed. Functional recovery in group of cMSC was increasing gradually after transplantation and was higher than nMSC. In MRI, we could not confirm any difference between the cMSC and nMSC experimental groups. Immunohistochemically, beta3-tubuline and nestin were observed in injury site of two experimental groups with the expression level close to non-injured groups. Transplantation of mesenchymal stem cells could promote neuronal reconstruction and repair motor function in SCI. These showed mesenchymal stem cells could be a great candidate as a therapeutic tools in degeneration disease, and dogs could be used to explore human regenerative medicine as a promising animal model. This research was supported by iPET (Grants 110056032CG000), Ministry for Food, Agriculture, Forestry and Fisheries, Republic of Korea.
        38.
        2011.10 구독 인증기관·개인회원 무료
        Acteoside (verbascoside) is a typical phenylethanoid glycoside, extracted from various plants. It has various biological functions such as anti-oxidant, anti-inflammation, and anti-hypertension. Specially, it was powerful anti-oxidants either by direct scavenging of reactive oxygen and nitrogen species, or by acting as chain-breaking peroxyl radical scavengers. We examined the role of acteoside in IVM medium on the morphological progress of meiosis, developmental competence, and ROS in porcine oocytes. And we investigated effect of acteoside on the oocytes condition represented by cytoplasmic maturation by homogeneous distribution and formation of cytoplasmic organelles and regulation of apoptosis-related genes. The selected COCs were cultured in TCM-199 with various concentration of acteoside: 0 (control), 10, 30, and 50 μM. After 22 h of maturation with hormones, the oocytes were washed twice in a fresh maturation medium before being cultured in hormone-free medium for additional 22 h. The oocytes maturation rates of supplemented with acteoside were no significantly different compared with control group (71.13, 75.96, 72.95 and 73.68%, respectively). Level of ROS was significantly decreased in acteoside treated group. Furthermore, the parthenogenetic blastocyst rate was significantly improved in 10 μM acteoside treated group compared with control group (40.03 vs. 22.95%). During IVM, 10 μM acteoside treated oocytes showed that the mitochondria and lipid droplet were smaller and homogeneous distribution in cytoplasm compare with non-treated control oocytes. And reverse transcription polymerase chain reaction (RT-PCR) witarthenogenetic blstocysts revealed that acteoside increased the anti-apoptoticgenes, otherwise reibued pro-apoptotic genes. In conclusion, our results represents that addition of acteoside to the IVM medium has a beneficial effect in physiology of porcine oocytes such as viability and activation, providing a improved method for porcine oocytes in vitro.
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