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        검색결과 1,238

        701.
        2013.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Embryos formed in vivo were collected from 171 donors housed in Chung Cheong Buk-Do Institute of Livestock and Veterinary Research of the Chungbuk community during the years 2009∼2012. We evaluated annual embryo collection, effect of follicle stimulating hormone (FSH), controlled internal drug release (CIDR) and prostaglandin (PG) administration to the donor for superovulation and controlling the estrus cycle, seasonal effects of embryo collection and compared the number of embryos recovered as per the collection days and pregnancy rate. In all, 1,243 embryos were collected from 118 donors with an average of 7.31 ± 5.35 embryos per donor, out of which 69.4% were transferable. Dosages of FSH required for inducing superovulation in various donors were compared. Average number of embryos collected from donors administered with 30 AU of FSH (7.13 ± 5.74 per donor) was not significantly different from that of donors who were given an injection of 24 AU of FSH (7.53 ± 4.91 per donor). However, the percentage of transferable embryos in the 30AU FSH-administered group (63.2 %, 449 of 711) was higher than that in the 24AU FSH-administered group (77.8%, 414 of 532). In the group of donors under a natural estrus cycle, the FSH dose administered did not influence the number of transferable embryos produced (7.49 ± 6.25 per donor for 30 AU of FSH vs 7.49 ± 4.92 per donor for 24 AU of FSH). However, in donors administered with CIDR and PG for controlling the estrus cycle, the FSH dose affected the average number of transferable embryos collected (4.25 ± 2.87 per donor for 30 AU of FSH vs 8.50 ± 6.36 per donor for 24 AU of FSH). We collected embryos from donors 6, 7 or 8 days after artificial insemination (AI). Results showed that the percentage of transferable embryos among those collected 8 days after AI was significantly higher than that among embryos collected 6 or 7 days after AI. Seasonal variations did not affect number of recovered embryos and pregnancy rates in natural estrus cycle and CIDR treatment groups (48.28% and 42.55%) but higher than pregnancy rate of frozen embryos (19.63%). These results indicated that administration of FSH beyond a threshold dose (at least 24 AU) has no beneficial effect on the production embryos and that collection of embryos 7∼8 days after AI is optimal for embryo recovery. CIDR treatment induced superovulation in short term and had no influence on the natural estrus cycle. Finally, although good-quality embryos were transferred, freezing significantly reduced the pregnancy rates after transfer.
        4,000원
        702.
        2013.12 구독 인증기관 무료, 개인회원 유료
        In mammal, unfertilized oocytes remain in the oviduct or under in vitro culture, which is called "oocyte aging". This asynchrony negatively affects fertilization in pre- and post-implantation embryo development. Caffeine a phos-phodiesterase inhibitor is known to rescue oocyte aging in several species. The objective of this study is to determine the cytoskeleton distribution in aged oocytes and the embryo developmental ability of aged oocytes in the present or absence of caffeine during maturation. Caffeine treatment increased the incidence of normal spindle assembly of aged oocytes (treatment, 67.57±4.11% aging, 44.61±6.4%) and no significant differences compared to control group. Fluorescence values were compared using ROS (Reactive oxidation species) stain. Fluorescence values appear of con-trol group intensity rate (51.53.±3.80), aging group (68.10±5.54) and treatment of caffeine (45.04±2.98). Aged oocytes that were derived from addition of caffeine to the IVM (in vitro maturation) medium had significantly increased 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 fragments of genomic DNA were measured in individual embryo using TUNEL assay. Blastocyst derived from caffeine treatment group decreased significantly the apoptotic index compared to blastocyst derived from aging group. In conclusion, we inferred that the caffeine treatment during oocyte aging can improve the developmental rate and quality in bovine embryos developing in vitro
        4,000원
        703.
        2013.12 구독 인증기관 무료, 개인회원 유료
        Low efficiency of somatic cell nuclear transfer (SCNT) is attributed to incomplete reprogramming of transfered nu-clei into oocytes. Trichostatin A (TSA), histone deacetylase inhibitor and 5-aza-2’deoxycytidine (5-aza-dC), DNA methy-lation inhibitor has been used to enhance nuclear reprogramming following SCNT. However, it was not known molec-ular mechanism by which TSA and 5-aza-dC improve preimplantation embryo and fetal development following SCNT. The present study investigates embryo viability and gene expression of cloned porcine preimplantation embryos in the presence and absence of TSA and 5-aza-dC as compared to embryos produced by parthenogenetic activation. Our results indicated that TSA treatment significantly improved development. However 5-aza-dC did not improve development. Presence of TSA and 5-aza-dC significantly improved total cell number, and also decreased the apoptot-ic and autophagic index. Three apoptotic-related genes, Bak, Bcl-xL, and Caspase 3 (Casp3), and three autophagic-re-lated genes, ATG6, ATG8, and lysosomal-associated membrane protein 2 (LAMP2), were measured by real time RT-PCR. TSA and 5-aza-dC treatment resulted in high expression of anti-apoptotic gene Bcl-xL and low pro-apoptotic gene Bak expression compared to untreated NT embryos or parthenotes. Furthermore, LC3 protein expression was lower in NT-TSA and NT-5-aza-dC embryos than those of NT and parthenotes. In addition, TSA and 5-aza-dC treated embryos displayed a global acetylated histone H3 at lysine 9 and methylated DNA H3 at lysine 9 profile similar to the parthenogenetic blastocysts. Finally, we determined that several DNA methyltransferase genes Dnmt1, Dnmt3a and Dnmt3b. NT blastocysts showed higher levels Dnmt1 than those of the TSA and 5-aza-dC blastocysts. Dnmt3a is lower in 5-aza-dC than NT, NTTSA and parthenotes. However, Dnmt3b is higher in 5-aza-dC than NT and NTTSA. These results suggest that TSA and 5-aza-dC positively regulates nuclear reprogramming which result in modulation of apoptosis and autophagy related gene expression and then reduce apoptosis and autophagy. In addition, TSA and 5-aza-dC affects the acetylated and methylated status of the H3K9.
        4,200원
        704.
        2013.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Brucella spp. are facultative intracellular pathogens that have the ability to survive and multiply in professional and nonprofessional phagocytes and cause abortion in domestic animals and undulant fever in humans. Brucella species can survive in a variety of cells, including macrophages and their virulence and chronic infections are thought to be due to their ability to avoid the killing mechanisms within macrophages. Inhibition of phagosome-lysosome fusion has been proposed as a mechanism for intracellular survival of Brucella in professional and nonprofessional phagocytes. Toll-like receptors (TLRs) are part of a skillful system for detection of invasion by microbial pathogens. Recognition of microbial components by TLRs triggers signaling pathways that promote expression of genes and regulate innate immune responses. Recent studies for the interaction between TLRs-Brucella have indicated the importance of control of Brucella infection. Here, we review selected aspects of TLRs-Brucella interaction, which may be helpful to understanding the mechanism of Brucella pathogenesis.
        4,000원
        705.
        2013.10 구독 인증기관 무료, 개인회원 유료
        The multi-tactile stimulation system was developed to analyze cognitive function characteristics. The developed system consists of three units; control unit, drive unit and actuator that simultaneously and separately supports the vibration, heat, and pressure stimulation. From the results, vibration stimuli have a wide frequency range of 0-300 Hz comprising 20 levels, and stimulation intensity comprising 40 levels. The control temperature and stimulation temperature used for heat stimulation comprise four and eight levels, respectively. Pressure stimuli in the range of 0-600 mmHg can be stimulated comprising 12 levels. Therefore, the developed stimulator can be used for integrative tactile perception and cognition studies on various vibration, heat and pressure sensations.
        3,000원
        706.
        2013.10 구독 인증기관 무료, 개인회원 유료
        In this paper, we developed a power amplifier system for driving a solenoid coil. The developed system consists of three units; control unit, drive unit and coil. The control unit generates a drive signal of sinusoidal wave type, monitors an operating status of the drive unit and vibration characteristics of the coil. The drive unit drives a solenoid coil in response to command from the control unit. The coil was fabricated with the size of diameter in 1.5 cm and length in 1.7 cm using electric copper wire. 4 types of drive unit were tested with thermal and vibration characteristics of the coil using temperature sensor and 3-axis accelerometer, respectively. From the result, the developed system has many advantages with respect to simple control algorithm, small size, and operates stably up to 68 watts driving condition.
        3,000원
        710.
        2013.10 구독 인증기관 무료, 개인회원 유료
        There are many different types of heating methods in the world. Most of these heating methods are through radiation and convection. These heating types emphasize insulation because it is important to maintain the indoor air temperature. In contrast, the ondol, emphasizes thermal storage in the floor because it heats conduction. In other words it heats through direct contact. This unique heating method has created a unique interior environment. Activities have to occur close to the floor so that people may come in direct contact with the heat, thereby influencing the cultural development of the Korean people. The ondol has also created an interior environment where it is warmer near the floor than the ceiling in contrast to other heating systems where the area close to the ceiling is warmer. This environment is inline with the optimal healthy conditions the Koreans prefer, the warm feet cool head environment.
        4,000원
        711.
        2013.10 구독 인증기관·개인회원 무료
        The melon and cotton aphid Aphis gossypii Glover (Hemiptera; Aphididae) is one of the most serious pests worldwide. We surveyed insecticide susceptibility in A. gossypii field populations to 12 insecticides (6 neonicotinoids, 3 pyrethroids and 3 others) to examine resistance ratios. The levels of insecticide resistance were extremely high, especially to neonicotinoids, such as acetamiprid, clothianidin, thiacloprid and imidacloprid. To identify the neonicotinoid resistance mechanisms, we used an imidacloprid-resistant (IMI-R) strain as a model strain. IMI-R showed an extremely high resistance ratio and also cross-resistance to all the test neonicotinoids. However, there was little or no cross-resistance to the other insecticides, including sulfoxaflor. Synergist tests and enzyme activity assays suggested the absence of resistance mechanisms based on enhanced detoxification enzymes, such as cytochrome P450, esterase and glutathione S-transferase. One point mutation was found in the beta1 subunit loop D region of the nicotinic acetylcholine receptor (nAChR) of the IMI-R strain. This R81T point mutation was also found in field populations collected from 5 regions. Therefore, the R81T point mutation was identified as an important mechanism of imidacloprid resistance in A. gossypii.
        712.
        2013.10 구독 인증기관·개인회원 무료
        We sequenced 17,329 bp of mitochondrial genome (mitogenome) of the black dwarf honey bee, Apis andreniformis (Hymenoptera: Apidae), that lacks ~200 bp of the A+T-rich region for the completion of the genomic sequence. The gene arrangement of A. andreniformis mitogenome is identical to that of A. cerana. However, the genome contains 5 additional tRNALeu(CUN) located 4 copies between tRNAMet and tRNAGln, and 1 copy between tRNAGln and tRNAAla, along with the typical sets of genes (13 protein-coding genes, 22 tRNAs, and 2 rRNAs) including regular tRNALeu(CUN) and the A+T-rich region (at least 923 bp). Only 1 copy of tRNALeu(CUN) differed by 1 bp from other 4 copies of tRNALeu(CUN). Each additional tRNALeu(CUN) is followed by nearly identical 68-bp long repeat sequence (95.6% identity). All 13 protein coding genes have typical start codons found in insect mitochondrial PCGs (2 ATA, 9 ATT, and 2 ATG).
        713.
        2013.10 구독 인증기관·개인회원 무료
        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.
        714.
        2013.10 구독 인증기관·개인회원 무료
        The effect of electron beam irradiation on development and reproduction of imidacloprid-resistant (R strain) and -susceptible (S strain) Aphis gossypii were compared. Nymphs and adults of R and S strain were irradiated at target doses of 50, 100, 150, and 200 Gy. When nymphs were irradiated, emergence was not affected at all target dose, but number of F1 nymph 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 of F1 nymph was decreased at 100 Gy and completely inhibited at 200 Gy. However, there were no significant differences on development and reproduction of R and S strain. We also conducted the comet assay immediately after irradiation and over the following 10 day period. Severe DNA fragmentation in A. gossypii cells was observed just after irradiation and the damage was repaired during the post-irradiation period in a time-dependent manner. These results suggest that electron beam irradiation induced abnormal development, reproduction, and DNA damage in A. gossypii, but there were no significant differences between R and S strain.
        715.
        2013.10 구독 인증기관·개인회원 무료
        A major concern in exporting agricultural commodities is the introduction or spread of exotic quarantine pests to the new area. To prevent spread of insect pests, various phytosanitary measures are used. In this study, we compared the effect of electron beam and X-ray irradiation on development and reproduction of the two-spotted spider mite, Tetranychus urticae. Eggs, nymphs, and adults were irradiated at target doses of 50, 70, 100, 150, 200, 250, and 300 Gy with electron beam and 10, 20, 30, 50, 70, 100, 150, and 200 with X-ray irradiation. When eggs were irradiated, egg hatching was completely inhibited at 150 Gy of electron beam and 50 Gy of X-ray irradiation. When irradiated to the nymphs, emergence was not affected at all target dose in both electron beam and X-ray irradiation. Hatchability of F1 generation was significantly decreased at 100 Gy of electron beam and 70 Gy of X-ray irradiation. When irradiated to the adults, longevity did not show any differences at all target dose in both electron beam and X-ray irradiation. These results suggest that the effect of X-ray irradiation was more potential than electron beam irradiation.
        716.
        2013.10 구독 인증기관·개인회원 무료
        It is true that the proper environmental risk assessments for many GM insects almost have not been executed in Korean research situation. Therefore, we tested the environmental risk assessment of GM silkworms if there is any difference between GM and non-GM silkworms by three. First, we measured their mobility in the breeding environment conditions with food and without food. Secondly, we measured their viability at the Korean artificial extreme environmental conditions (temperature, humidity, food) after escaping from their breeding environments. We observed the egg productivity and the hatchability between non-GM silkworm and transgenic silkworms with four different pair experiments. The mobility of non-GM silkworms and GM silkworms statistically did not differ and the egg production and hatchability was not also different. The hatchability by couple of GM female silkworm and non-GM male silkworm was lower than by non-GM male and female couple. We observed their viability (High Temp., wet and with food: p=0.0434; High Temp., wet and without food p=0.0430; High Temp., dry and with food: p=0.0005; High Temp., dry, without food: p=0.0479) between the GM silkworm and non-GM silkworm, and there was statistically different. Relatively, the viability of GM silkworm was lower than non-GM silkworms. We could not exactly test for viability of silkworm in low temperature conditions because of their hibernating. Although there was any difference in viability and hatchability between GM silkworm and non-GM silkworm, the all ability of GM silkworm was lower than non-GM silkworm. Conclusively, risk of GM silkworm was lower than non-GM silkworm.
        717.
        2013.09 구독 인증기관 무료, 개인회원 유료
        Patients referred to the Veterinary Medical Center at Chungbuk National University were analyzed. This study aimed to provide information to clinicians in Korea on the factors affecting fracture incidence in patients adapted to Korean companion animal culture. Eighty cases showing- bone fractures were investigated from January, 2005 to De- cember, 2011. Fractures were mainly observed in miniature dogs such as Yorkshire terrier (12%), Poodle (12%), and Maltese (9%). Almost 50% of all cases were less than 1 year old. Total bone fractures in summer and fall constituted 62%. Fracture incidence was higher in male dogs (54%) than female dogs (46%). Hindlimb fracture (37%) was the most common. Distribution of limb fractures was higher in the femur (19), followed by the tibia/fibula (15), radius/ulna (13), humerus (11), and mandible (8). Pelvic fracture was observed in 19 cases. Simple fracture (84%) was the most common fracture type, followed by comminuted fracture (16%). Distal portion was the most common fracture site in long bones (67%), followed by middle (26%) and proxi- mal bones (7%). Fractures were mainly caused by traffic accidents (43%), whereas 28.5% of fractures were due to falling down. Plate & screw (26%) was the most common method of fracture repair, followed by intramedullary pin (24%), wire (11%), external skeletal fixation (10%), screw (9%), amputation (7%), cross pin (6%), IM pin and wire (5%), and rush pin (1%). Among 80 patients, 79%of pa- tients showed a good prognosis after surgery, whereas 13% patients did not experience a good result. This study shows that miniature dogs are prone to falling and fractures, espe- cially in the distal part of long bones.
        4,000원
        719.
        2013.06 구독 인증기관 무료, 개인회원 유료
        Vitamin C (ascorbic acid) is an essential nutrient of most living tissues. We established a strain of Gulo-/- mice with known deficiency, in which vitamin C intake can be controlled by diet, like humans, and investigated the differen- tially expressed proteins following treatments with Helicobacter pylori and diethylnitrosamine (DENA) in the liver of Gulo-/- mice using a proteomic approach. Expression of p53, 14-3-3ε and 14-3-3δ in Gulo-/- mice liver tissue was analyzed by immunohistochemistry. 2-DE maps constructed from Gulo-/- mice liver and differentially expressed proteins in liver tissue were identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF/MS). In Gulo- /- mice after H. Pylori infection, followed by treatment with DENA, no differences in p53, 14-3-3ε and 14-3-3δ were observed by immunohistochemistry. Proteome analyses us- ing MALDI-TOF/MS resulted in successful identification of 12 proteins (nine proteins were up-regulated and three were down-regulated). Specifically, peroxiredoxin-6 and Alpha-1-antitrypsin 1-4 were up-regulated in liver after H. Pylori infection followed by treatment with DENA. These results indicated that oral supplementation with vitamin C led to rescue of Gulo-/- mice from vitamin deficiency, and protected the liver from H.pylori infection and/or DENA ef- fect, and vitamin C also protected the liver against oxidative stress.
        4,000원
        720.
        2013.06 구독 인증기관 무료, 개인회원 유료
        An efficient plant regeneration protocol is developed for a standard-type chrysanthemum. When petal segments derived from flower buds (4 or 8cm in diameter) were used as the culture material, the highest shoot regeneration frequency (96%) was obtained on a Murashige and Skoog (MS) medium supplemented with 0.5 mg/L IAA, 2 mg/L BA, 3% sucrose, and a 0.8% agar. Pre-culturing the explants under dark conditions for 14 days produced better results for the shoot regeneration frequency than the explants cultured under a continuous 16 h photoperiod (40 μmolm-2 s -1 ). The shoot regeneration frequency ranged from 19.0% for the Shinmato cultivar to 89.1% for the Baeksun cultivar. Activated charcoal (0.2%) enhanced the root formation of the regenerated shoots in a hormone-free MS medium. The rooted plantlets were acclimatized and successfully established in a greenhouse.
        4,000원