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        검색결과 1,260

        765.
        2012.10 구독 인증기관·개인회원 무료
        Fumigant effects of six plant essential oils (Helichrysum angustifolia, H. gymnocepha, H. splendidum, Arachis Hypogaea (peanut oil), Mentha arvensis (corn mint oil), and Thymus magnus (thyme oil) were tested against the adults of three grain storage insects (Lasioderma serricorne, Sitophilus zeamais, and Tribolium castaneum). Among them, the corn mint oil revealed to have fumigant toxicity against L. serricorne (LD50 = 1.3 ㎕ L-1), S. zeamais (LD50 = 3.6 ㎕ L-1), and T. castaneum (LD50 = 16.2 ㎕ L-1). The chemical constituents of corn mint oil were analyzed using GC-MS as follows: (-)-menthone (15.3%), isomenthone (10.0%), methyl-cetate (5.0%), β-caryophyllene (9.1%), and 1-menthol (48.1%). To enhance the fumigant toxicity, ethyl formate was added. This novel formulations of mixture could find significant differences in terms of their synergistic effects.
        767.
        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.
        768.
        2012.10 구독 인증기관·개인회원 무료
        Termites are a major problem for home and business owners around the world. Termites gnaw through wood and burrow under the foundations of buildings causing a great deal of damage to the structure of the building. Phosphine (PH3) is very effective fumigant and is widely used to control pests. PH3 rapidly penetrate through treated material, so it replaced many conventional fumigants for treatment of durable materials. In this study, we have investigated the effectiveness of PH3 fumigation on wood pests, Reticulitermes speratus kyushuensis. We evaluated two bioassay methods; wooden cube (10×10×10 cm) and insect breeding dish in comparison with effectiveness of PH3 penetrations into the timber block. Fumigation to adults of R. speratus was carried in a desiccator system for 24 h at 5 and 15℃. As a result, LC99 of PH3 to R. speratus in wooden cubes and insect breeding dish at 5℃ was 0.183 and 0.177 mg L-1, respectively. LC99 of PH3 in wooden cubes and insect breeding dish at 15℃ was 0.077 and 0.078 mg L-1, respectively. There were no significant differences between the two bioassay methods. Thess results indicate that PH3 described herein merit further study as potential fumigants for termite control.
        769.
        2012.10 구독 인증기관·개인회원 무료
        The cotton aphid, Aphis gossypii (Glover) (Hemiptera:Aphididae), is a highly polyphagous pest that directly or indirectly damages cultivated plants. Six field-collected populations of cotton aphid, A. gossypii (BY-A, BY-B, YJ-A, YJ-B, CJ-A, and CJ-B) were tested for susceptibility to 14 different insecticides. Most population exhibited high to very high levels of resistance to neonicotinoid. Among them, a strain showing resistance to imidacloprid were selected and showed 1,543-fold in resistance as compared with susceptible strain. Piperonyl butoxide (PBO), diethyl maleate (DEM), and S,S,S tributyl-phosphorothiolate (DEF) failed to synergize imidacloprid in this resistant population. In addition, the activity of detoxification enzymes (P450, EST, GST) were no differences between susceptibility and imidalcoprid resistance strain. However, by analyzing the nicotinic acetylcholine receptor β1 subunit loop D, R81T point mutation was detected in BY-A, BY-B, YJ-A, and YJ-B strain.
        770.
        2012.10 구독 인증기관·개인회원 무료
        The effects of electron beam irradiation on life stage and reproduction of Spodoptera litura were examined. Eggs, larvae, pupae, and adults were irradiated at target doses of 30, 50, 100, 150, 200, and 250 Gy. When eggs were irradiated with 100 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 100 Gy and above. Also, electron beam 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. Adult longevity was not affected in all stages. The levels of DNA damage in S. litura adults were evaluated using the alkaline comet assay. Our results indicate that electron beam 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 electron beam irradiation induced abnormal development and reproduction by DNA damage in S. litura. and as time goes by, the DNA damage was decresed.
        771.
        2012.09 구독 인증기관 무료, 개인회원 유료
        In the gingival tissues of patients with periodontitis, inflammatory responses are mediated by a wide variety of genes. In this study, we screened for differentially expressed genes (DEGs) in periodontitis compared with normal tissue using an annealing control primer (ACP) system. By ACP RT-PCR analysis, we obtained about 160 amplicons, 8 of which were found to be differentially expressed. DEGs in patients with periodontitis were thus successfully and reliably identified by the ACP-based RT PCR technique. The DEGs identified in the screen may also enhance our understanding of the pathogenesis of periodontitis.
        4,000원
        772.
        2012.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was carried out to apply an optimized convenient assay, exploiting azo dye-bound chromogenic substrates, to measurement of protease activity. When determined for responses at varying concentrations of two substrates, azocasein and azoalbumin, using 0.5 and 5.0 mg/mL each of bovine pancreas trypsin, 3% azocasein was found to be the most appropriate substrate solution to measure protease activity. Compared with a conventional casein-Folin phenol assay, the chromogen-based protease assay exploiting 3% azocasein showed better precision to have a coefficient of variability in seven repetitive measurements less than 1.11%. When various reagent-grade and industrial proteases that showed proteinase or peptidase activities were tested by this assay at increasing enzyme concentrations, typical shape of rectangular hyperbola in activity-enzyme concentration profiles was observed. In addition, the assay of this study was suitable for activity measurement in real samples that were prepared by hydrolyzing wheat gluten and anchovy fine powder with proteases.
        4,000원
        773.
        2012.06 구독 인증기관 무료, 개인회원 유료
        The objectives of the current study were to evaluate the therapeutic effect of dioctahedral smectite (smectite) against calf diarrhea caused by pathogenic E. coli and/or Salmonella typhimurium. In this study, 20 calves (aged 2~3 months) with diarrhea were used for evaluation of the efficacy of smectite on calf diarrhea with 20% smectite suspension in PBS. Calves received 10 ml smectite suspension three times per day after feeding, and fecal samples were collected at the gate of treatment and on the first, second, third, fourth, and fifth day after administration. On the fifth day after treatment with smectite suspension, the diarrhea index showed a significant decrease in the treated group, compared to the control group (P<0.001). The number of pathogenic E. coli in feces of the treated group was significantly decreased, compared to each control group from the second day after treatment (P<0.001), and that of Salmonella typhimurium was significantly decreased from the first day after treatment (P<0.05). According to the results of the current study, 20% smectite suspension had a therapeutic effect on diarrhea caused by E. coli and/or Salmonella in calves.
        4,000원
        774.
        2012.06 구독 인증기관·개인회원 무료
        In this study, we examined whether Hanganutziu‐Deicher (H‐D) antigens are important as an immunogenic non‐a1,3‐galactose (Gal) epitope in pigs with a disrupted a1,3‐ galactosyltransferase gene. The targeting efficiency of the AO blood genotype was achieved (2.2%) in pig fibroblast cells. A total of 1800 somatic cell nuclear transfer (SCNT) embryos were transferred to 10 recipients. One recipient developed to term and naturally delivered two piglets. The a1,3‐galactosyltransferase activity in lung, liver, spleen, and testis of heterozygote a1,3‐galactosyltransferase gene knockout (GalT‐KO) pigs was significantly decreased, whereas brain and heart showed very low decreasing levels of a1,3‐ galactosyltransferase activity when compared to those of control. Enzyme‐linked lectinosorbent assay showed that the heterozygote GalT‐KO pig had more sialyla2,6‐ and sialyla2,3‐ linked glycan than the control. Furthermore, the heart, liver, and kidney of the heterozygote GalT‐KO pig had a higher N‐glycolylneuraminic acid (Neu5Gc) content than the control, whereas the lung of the heterozygote GalT‐KO pig had Neu5Gc content similar to the control. Collectively, the data strongly indicated that Neu5Gc is a more critical xenoantigen to overcoming the next acute immune rejection in pig to human xenotransplantation.
        775.
        2012.06 구독 인증기관·개인회원 무료
        Genomic reprogramming factors in the GV cytoplasm improved cloning efficiency in mice through the pre‐exposure of somatic cell nuclei to a GV cytoplasmic extract prior to nuclear transfer. In this study, a pig GV oocyte extract (pGV extract) was developed. Treatment of pig fibroblasts with the pGV extract promoted colony formation after 2–3 weeks in culture, concomitant with the expression of stem cell markers (Oct‐4, Rex1, Nanog, Sox2) and repression of differentiated cell markers (CKAP2, NPR3 ). Using fibroblasts transfected with human Oct‐4 promoter‐driven enhanced green fluorescent protein (Oct4‐EGFP), pGV extract treatment induced the reactivation of the Oct‐4 promoter in Oct4 ‐ EGFP cells by 10 days post‐treatment. These transgenic donor cells were injected into 8‐cell embryos. Oct‐4 promoter activity was subsequently detected in most ICM cells of the host blastocyst. Interestingly, reconstructed embryos with pGV extract‐treated Oct4‐ EGFP fibroblast nuclei showed prolonged expression of Oct4 in the ICM of embryos. Additionally, the pGV extract promoted somatic cell reprogramming and cloned embryo development when assessed by measuring histone H3‐K9 hypomethylation, the expression of Oct4 and Nanog in blastocysts, and the production of increased numbers of high‐ quality blastocysts. Under specific culture conditions, pGV extract‐treated fibroblast cells differentiated into neuronal, pancreas, cardiac, and endothelial lineages that were confirmed by antibodies against specific marker proteins. These data provide evidence for the generation of stem‐like cells from differentiated somatic cells by treatment with GV oocyte extracts in pig.
        776.
        2012.06 구독 인증기관·개인회원 무료
        Accumulating evidence suggests that chemotherapy can cause long‐term detrimental effects and alter the biology of the recipient environment. Therefore, a subsequent report claimed that the transplantation of female germline stem cells (FGSCs) into the ovaries of recipient mice that were pretreated with a high dose of busulfan and cyclophosphamide (B/C) resulted in the successful production of offspring. Therefore, this study was conducted to further clarify the impact of female germ cell transplantation on female ovaries after B/C treatment. RT‐PCR analysis showed that the period of germ cell depletion coincide with decreased Figla, Lhx8, Nobox, Kit, and Sox3 gene expression in the B/Ctreated ovary. However, depletion of female germ cells is mediated by a Fas/FasL‐, Kit/ Kitl‐, TNF‐, p53‐ and autophagy‐ independent pathway. Also, histological analysis is similar to that of Nobox null‐derived ovaries, indicating that follicle death after B/C treatment might be caused by down‐regulating of Nobox pathway. When female mice during 15 weeks after B/C treatment were checked for reproductive activity, B/C treated mice did not produce their pups. In addition, when 3×106 GFP positive primordial follicles were injected into B/C treated female mouse ovaries, donor follicle were not able to colonize into the ovaries of recipients. In conclusion, these data from a preclinical mouse model strongly suggested that female ovary until 15 weeks after B/C treatment could not support environment for maturing of exogenous FGSCs.
        777.
        2012.06 구독 인증기관·개인회원 무료
        MAC-T cells, bovine mammary epithelial cell line, have been utilized to investigate bovine lactation system. A lactogenic phenotype of the cell is generally induced by combination of dexamethasone, insulin and prolactin (PRL). Effect of vitamin A derivative retinoic acid (RA), well reported as an inducer for differentiation in many cells, to MAC-T cell has not been studied. The objective of this study was to confirm effect of differentiation potential by RA treatment in MAC-T cells and to test effect of combination of RA and PRL treatment. In RA or PRL treatment groups, both has induced morphological change to secrete milk of MAC-T cells. Combination of RA and PRL treatment group has presented noticeable lactogenic phenotype among the all group. This phenotype observed at four days after treatment and showed critical morphological change that was rouphly spherical structure at eight days. RA alone treatment showed slightly inhibition of proliferation in the MAC-T cells, but co-treatment with PRL was improved the cell growth more than control group. MTT assay result and Bcl-xL/Bax ratio of mRNA abundance also was entirely consistent with earlier one. RA-induced differentiation of MAC-T cells has increased αs1-casein, αs2-casein and β-casein mRNA expression compared to PRL treatment group. Expression of αs1-casein, αs2-casein and β-casein genes represented the maximum value in the combination of RA and PRL treatment group at four days. The value of each casein gene expression was 4-, 5.5- and 5.9-fold, respectively, as compared with PRL alone treatment in the MAC-T cells. Protein level of β-casein releasing to the medium also induced the highest level at four days. These results provide evidence that RA can induce the differentiation of MAC-T cells and have synergetic effect with PRL.
        778.
        2012.06 구독 인증기관·개인회원 무료
        Autophagy is conserved response to starvation by which cells catabolize their components to create an internal supply of essential nutrients. Ceramide is known to induce autophagy in many cells through down-regulation of amino acid and glucose transporters. The mechanism of starvation induced-autophagy in mouse embryo remains unclear. In order to understand the mechanism by which starvation regulates autophagy, in this study, we investigated nutrient transporters expression and the effect of c2-ceramide on the in vitro development, apoptosis and autophagy via starvation in mouse embryo. Glucose transporters (Glut1 and Glut 3), high levels of transcript were expressed from 1 to 2 cells and gradually decreased through the morula and blastocyst (BL) stages. Amino acid transporters (LAT-1 and 4F2hc) gradually decreased from the zygote to the BL stage. Furthermore, the expression of nutrient transporters (Glut1, 3, LAT-1 and 4F2hc) were significantly reduced at the BL stage after ceramide treatment. Especially, mTOR expression after ceramide treatment of embryos was significantly higher than controls. Ceramide treated embryos exhibited significantly reduced developmental rates and total cell numbers, and increased apoptotic cell death at the BL stage. Consequently, we next evaluated the effect of ceramide treatment on mitochondrial number and morphology. There was a significant decrease in the average mtDNA copy number and the mitochondrial area in ceramide treated BL stage embryos. Both the expression of autophagy-related genes, Lc3, Gabarap, Atg4A and Atg4B, and the synthesis of LC3 were significantly induced at the BL stage. These results suggest that autophagy under starvation condition influences the in vitro development and apoptosis and autophagy, and may play a role in early mouse embryogenesis.
        779.
        2012.06 구독 인증기관·개인회원 무료
        In mammal, oocytes are arrested at the metaphase Ⅱ until fertilization. However, unfertilized oocytes that remain in the oviduct or under in vitro culture, which is called "oocyte aging". Asynchrony negatively affects fertilization, pre- and post-implantation embryo development. Caffeine is known to phosphodiesterase inhibitor that rescues oocyte aging in several species. Nevertheless, the effect of caffeine was not clear in bovine aging oocytes. In this study investigated the cytoskeleton distribution in aged oocytes and the embryo development ability of aged oocytes from treated with or without caffeine during maturation. The cumulus and oocyte complexes (COCs) were cultured in 10% FBSTCM199 for up to 22h at 38.5℃ in 5% CO₂. For oocyte aging study, the COCs were cultured in 10% FBS-TCM199 supplemented with or without 10 mM caffeine for 40hs. And then oocytes underwent in vitro fertilization using highly motile sperm recovered from frozen and than thawed bull semen. As a result normal cytoskeleton percentage of caffeine treatment group more than the aging group (67.57%±4.11 VS 44.61%±6.40) and no significantly different compared to control group. Aged oocytes derived from addition of caffeine to the in vitro maturation medium significantly increased the percentage of 2- cell that developed to the blastocyst stage compared to the aging group. Blastocysts derived from caffeine treatment group significantly increased the total cell number compare aging (90.44%±10.18 VS 67.88%±7.72). Apoptotic fragmenting of genomic DNA was measured in individual embryos using the TUNEL assay. Blastocyst derived from caffeine treatment group significantly decereased the apoptotic index compared to blastocyst derived from aging group. In conclusion, we inferred that the caffeine treatment during oocytes aging periode can improved the develpmental rate and quaility in bovine embryos developing in vitro.
        780.
        2012.06 구독 인증기관·개인회원 무료
        Doxorubicin, a widely used chemotherapeutic agent, were found rapidly undergo morphological and biochemical changes via discrete effector signaling pathways consistent with the occurrence of apoptosis of oocyte. In this report, we elucidated the molecular requirements for actions of this drug in early embryos. Poly (ADP-ribose) polymerase (PARP), a DNA repair enzyme, and its homologues have recently been shown in female oocyte cells. However, the cleavage of PARP by caspase-3 inactivates it and inhibits PARP's DNA-repairing abilities. Cleaved PARP (cPARP) may be considered a marker of apoptosis. Doxorubicin inhibited the early embryo development, but the treatment could still reach the BL (blastocyst) stage that suggested that involved in DNA synthesis and repaired progress. Herein, the higher expression of PARP family shown especially in 2, 4 cell stagy. There was evidence of expression of Caspase3 and Bcl2l1 during embryogenesis (2 cell, 4 cell, morula and BL stage), suggesting that modulations of apoptosis-related genes and PARP were cause by DXR. Furthermore, the effect of doxorubicin on early embryo development was assessed different stage rates, and apoptosis index also conformed doxorubicin modulate embryo development by regulating apoptosis-related genes and PARP family genes. In conclusion, Doxorubicin blocked pre-implantation development in early mouse embryos by altering apoptosis-related gene expression and inactivating DNA repair by Parp.