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        검색결과 819

        461.
        2012.06 구독 인증기관·개인회원 무료
        Semen can be divided into two parts. One is cellular part which contains sperms the other is liquid part which is called by seminal plasma. The seminal plasma is a nutritive and protective medium for the sperms. Fructose, which is major energy source, is supplied to sperms swim to female oocyte. Alkalic property protects sperms from hostile environment of female reproductive organ. Also, seminal plasma induces tolerance to preexisted immune cells, and changes intra‐uterine environment to better conditions for fertilized embryos to implant. However, the effects of seminal plasma in in vitro culture of fertilized embryos are unclear. Second fraction of fresh semen was obtained from a normal farm pig. The semen was centrifuged to remove sperms, and then supernatant was filtrated. The filtered seminal plasma was stored in — 30℃. In this study, electrically activated and chemically activated porcine embryos were employed to investigate the developmental rate after 2 hours treatment of none, 0.1%, 0.5%, and 1% seminal plasma in culture media by two days of activation. Both electrically and chemically activated embryos, cleavage rate and cell numbers of blastocysts were not significant difference within four groups. Blastocyst formation rate of electrically activated embryos also did not show significant difference within any groups. However 0.1% seminal plasma treatment group showed significantly increase of blastocyst formation rate in chemically activated group (None; 24.8%, 0.1%; 31.7%, 0.5%; 19.4, and 1%; 16.5%, respectively. p<0.05).
        462.
        2012.06 구독 인증기관·개인회원 무료
        XIST has been known to long-non coding RNA which regulate X-chromosome inactivation in female mammal and the gene has been suggested to having important role in early embryo development and embryonic stem cell. However, its coding region has been unclear in pig. To determine the coding region of XIST in pig, we have examined candidate site of XIST coding region in pig by BLAST, PCR, and sequencing. By comparing pig whole genome sequence (Sus scrofa 10.2) with human, murine, and bovine XIST transcript sequence using BLAST, we selected candidate coding region of XIST in pig. The result showed XIST is coded on the minus strand of NW_003612825 contig and its length was nearly 32kb which was similar to the length of human and bovine XIST gene. With the candidate model, we performed RT-PCR to confirm the coding region of XIST with 24 primer pairs and they were expressed only female porcine embryonic fibroblast (PEF) but not in male PEF. By designing candidate intron spaning primer we could confirmed candidate intron is present between first and last exon (distance, 9.2kb vs product size, 2kb). The seqeucne of amplicon was analyzed and we could confirmed there were 5 small exons (less than 400 bp) like XIST coding region of other species which have 4 to 5 small exon between first and last exon. To confirm coding strand in pig, we conducted strand specific reverse transcription. We confirmed candidate XIST was coded on the negative strand of contig on X-chromosome as the result of homology analysis by BLAST. With the candidate pig XIST sequence, we aligned the sequence with XIST sequences of 3 species, human, mouse, and bull by clustalW. These result showed candidate sequence of pig XIST is most similar to that of bovine and the homology between pig and human was higher than result between mouse and human. These results could support for X chromosome inactivation analysis and the function of XIST in pig preimplantation embryos. * This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. 2012006276)
        463.
        2012.06 구독 인증기관·개인회원 무료
        Cordycepin, a specific polyadenylation inhibitor, is the main functional component in Cordyceps militaris that is one of the top three renowned traditional Chinese medicines. In this study, we performed in vitro experiments to investigate the anti-invasive and anti-metastatic activities of cordycepin using human prostate carcinoma LNCaP cells. Cordycepin were administered and their effects on LPS-induced cell migration and invasion by wound healing migration assay, measurement of TER and In vitro invasiveness assay. Within the concentrations which were not cytotoxic effects, cordycepin caused a concentration-dependent suppression of LPS-induced cell migration and invasion. The anti-invasive activity of cordycepin was also found to be associated with increased tightness of the TJ, which was confirmed by an increase in TER. The activity of MMP-2 in LNCaP cells was dose-dependently inhibited by treatment with cordycepin, and this was also correlated with a decrease in expression of its mRNA and proteins, and up-regulation of TIMPs expression. Additionally, cordycepin repressed the LPS-induced NF-kB activation and phosphorylation of PI3K/AKT. Taken together, these findings suggest that cordycepin inhibited LPS-induced migration and invasion of LNCaP cells by down-regulating the expression and activity of MMP-2, and the possible targets may be NF-kB and PI3K/AKT.
        464.
        2012.05 구독 인증기관·개인회원 무료
        With the increasing trend of global trades and protection of agro-ecosystem in importing and exporting countries against quarantine pest, quarantine and pre-shipment(QPS) fumigation in perishable commodites like strawberry is critical in terms of quality maintenance of fumigated commodites. Currently, there are limited use of MB fumigation on fruits and vegetables due to low temperature storage and phytotoxic effect or damage in postharvest qualities in many commodites. In this paper, efficacy and quality accessment of methyl bromide(MB) alternatives, ethyl formate and phosphine gas are presented for export strawberry. Efficacy of phosphine gas and ethyl formate are described in terms of concentration × time (CT) products to Frankliniella occidentalis, Aphis gossypii and Myzus persicae.
        466.
        2012.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study is to identify which width of the base of support(BOS) is safer and more effective in lifting by comparing muscle activations and body sways when lifting objects under the width variation of the BOS. A total of fifteen healthy adults participated in this study. For the width variation of the BOS, the participants changed the width between their feet into three different types(10cm, 32cm, 45cm) and lifted a 10kg four times in each type after going up on a force plate. In order to measure body sways according to the width variation of the BOS, a motion analysis system was used. In addition, in order to measure the muscle activations of lower extremities, including the erector spinae, gluteus maximus, rectus femoris, and tibialis anterior, an electromyogram(EMG) analysis was employed. In addition, the Borg's scale was drawn by quantifying the subjective discomfort levels felt from each width of the BOS. In conclusion, no statistically significant differences according to the width variation of the BOS were observed(p=.295, .308)(p>.05). However, a statistically significant difference was exhibited between the Borg's scale, which indicates the discomfort levels from lifting performances, and the width variation of the BOS (p=.000*).
        4,000원
        467.
        2012.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Both iron-deficient and zinc-sufficient diets have been known to be associated with a decreased risk of colon cancer. We investigated that effect of dietary zinc on the formation of colonic aberrant crypt foci (ACF) induced by azoxymethane (AOM) followed by dextran sodium sulfate in iron-deficient mice. Five-week old ICR mice were acclimated for 1 week and fed on iron-deficient diet (4.50 ppm iron) with three different zinc levels (0.01, 0.1, and 1.0 ppm) for 12 weeks. The total number of aberrant crypt (AC) and ACF was measured in the colonic mucosa after methylene blue staining. The total ACF numbers of low Zn (LZn), medium Zn (MZn) and high Zn (HZn) diet groups were 10.00 ± 2.67, 8.78 ± 3.12, and 7.96 ± 2.44, respectively and there were no significant differences among the groups. However, the total AC numbers of HZn (27.07 ± 3.88) and MZn (26.39 ± 5.59) diet groups were significantly low compared to LZn (22.57 ± 5.09) diet group (p<0.01). Cytosolic SOD activity was the highest in LZn diet group. But thiobarbituric acid-reactive substances level in liver was also the highest in LZn diet group compared to other groups. There is no difference in cell proliferation in mucous membrane among the groups, while apoptotic positive cells were increased in the HZn diet group. The high zinc diet exhibited decreased β-catenin-stained areas on the mucous membrane of colon compared to the LZn or MZn diet group. These findings indicate that dietary zinc might exert a modulating effect on development of ACF/AC in the mice with iron-deficient status.
        4,200원
        468.
        2012.03 구독 인증기관 무료, 개인회원 유료
        Iron nanoparticles (Fe-NPs) have recently been used for cancer diagnosis and therapy for imaging contrast and drug delivery. However, no study on nutritional bioavailability of Fe-NPs in the body has been reported. Ascorbic acid (AA) is known to aid in absorption of iron in the stomach by reducing Fe (III) to Fe (II). In this study, we investigated the bioavailability of Fe-NPs with AA in iron-deficiency-anemic mice in comparison with non-nano iron particles. Iron-deficient anemia was induced by feeding an iron-deficient diet (4.5 mg Fe/kg) and ocular bleeding from retro-orbital venous plexus for four weeks. Normal control mice were given a normal diet (45 mg Fe/ kg). After induction of anemia in mice, anemic mice received daily oral administration of Fe (40 mg/kg B.W.) + AA (5 g/kg B.W) and Fe-NPs (40 mg/kg B.W) + AA (5 g/kg B.W). After sacrifice, liver and spleen tissues were observed by haematoxylin & eosin stain. Amount of trace iron in liver and upper small intestine was investigated using an inductively coupled plasma-atomic emission spectrometer. Red blood cells (RBC), hematocrit (Hct), hemoglobin (Hb), and total iron binding capacity were also measured. The concentrations of iron in the Fe-NPs + AA group were significantly higher in liver and in upper small intestine than that in the Fe + AA group. The values of RBC, Hct, and Hb in the Fe-NPs + AA group were more rapidly increased to normal values compared with the Fe + AA group with increasing time. These results suggest that Fe-NPs in the presence of AA may be more bioavailable than non-nano Fe in Fe-deficient anemic mice.
        4,200원
        469.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Well-aligned multi-walled carbon nanotubes (MWCNTs) were successfully synthesized by catalytic chemical vapor deposition using a hydrogen sulfide (H2S) additive onto Al/Fe thin film deposited on Si wafers. Transmission electron microscopy images indicated that the as-grown carbon products were thin MWCNTs with small outer diameters of less than 10 nm. H2S plays a key role in synthesizing thin MWCNTs with a large inside hollow core. The well-aligned thin MWCNTs showed a low turn-on voltage of about 1.1 V/μm at a current density of 0.1 μA/cm2 and a high emission current of about 1.0 mA/cm2 at a bias field of 2.3 V/μm. We suggest a possible growth mechanism for the well-aligned thin MWCNTs with a large inside hollow core.
        4,000원
        470.
        2011.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The aim of this study was to investigate the effects of respiratory muscle training (RMT) with abdominal drawing-in maneuver (ADIM) on pulmonary function. Twenty-two subjects with restrictive breathing participated in this study. All the subjects were randomly assigned to three groups (7 subjects in RMT group, 7 subjects in RMT with ADIM group, 8 subjects in control group). The first group performed the RMT by using incentive respiratory spirometer (IRS). The second group performed the RMT by using IRS and the ADIM by using a Stabilizer. The exercises were conducted over four days. The pulmonary function was evaluated using the spirometer to measure the force exploratory volume in 1 second () and forced vital capacity (FVC). Measurements were conducted on the first day and the last day. A paired-t test was used for pre-post changes and the change rates in FVC and among each group were investigated by a one-way ANOVA. The findings of the the study were as follows: 1) There were significant differences of FVC and between pre and post in the two training groups (p<.05) 2) There was no significant difference of the change ratio the FVC and between the RMT group and RMT with ADIM group. Therefore, it is concluded that respiratory muscle and ADIM training, combined with two methods of treatment would suggest positive evidence for improving pulmonary function.
        4,000원
        471.
        2011.11 구독 인증기관·개인회원 무료
        Korea National Arboretum (KNA) is located in Gwangneung forest, between Namyangju-si and Pocheon-si, in Gyeonggi province. In KNA, there are 15 specialized plant gardens. The woody plants of 1,863 species and the herbaceous plants of 1,481 species have been maintained in these gardens for 500 years. KNA have suitable environments for fungal growth. Despite floral diversity in there, the intensive researches on fungal flora have not been studied to date. Therefore, in order to get informations on fungal flora, regular field trips were made to this area and fresh fungal specimens were collected from there for 48 days from May in 2007 to November in 2010. Total 1,522 higher fungal specimens were collected in Gwangneung forest. All the collected specimens were identified and classified in 8 classes, 19 orders, 69 families, 267 genera and 454 species, and deposited in the herbarium of Korea National Arboretum (KNA). Among the identified specimens, sixteenspecies were confirmed as new to Korea as follows: Cudoniella acicularis, Discina ancilis, Helvella costifera, Entoloma cephalotrichum, Entoloma lepidissimum, Mycena leptocephala, Naematoloma gracile, Sistotrema octosporum, Hydnellum peckii, Lachnellula calyciformis, Amanita cockeri f. roseotinctata, Micromphale foetidum, Mycena corynephora, Clitocybe lateritia, Physisporinus vitreus, and Datronia stereoides. Literature cited 1. 김현중, 한상국. 2008. 광릉의 버섯. 국립수목원. 420pp. 2. 今關六也, 本鄕次雄. 1987. 原色日本菌類圖鑑(I). 保育社. 325pp. 3. Breitenbach, J. and Kränzlin, Fred. 1984. Fungi of Switzerland: 1. Ascomycetes. Mykologia Luzern. 310pp. 4. Breitenbach, J. and Kränzlin, Fred. 1986. Fungi of Switzerland: 2. Non gilled fungi. Mykologia Luzern. 412pp. 5. Breitenbach, J. and Kränzlin, Fred. 1995. Fungi of Switzerland: 4. Agarics 2nd part. Mykologia Luzern. 368pp. 6. Singer, R. 1986. The Agaricales in Modern Taxonomy. Koeltz Scientific Books. 7. Smith, A. H., Smith, H. V. and Weber N. S. 1979. How to know the gilled mushrooms. Wm. C. Brown Company Publishers. pp. 27, 263, 286-287.
        472.
        2011.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study is to examine the effects of gait training using functional electrical stimulation on the improvement of hemiplegic patients' functions for balance and gait velocity. The subjects of the experiment were determined to be 10 each hemiplegic patients who had been diagnosed with stroke or brain damage six months or longer earlier assigned to an experimental group and a control group respectively. The subjects were evaluated before the experiment using Tetrax and 10M gait tests, received gait training five times a week for four weeks using functional electrical stimulation and were evaluated after the experiment in the same method as used in the evaluation before the experiment. In order to examine differences between the experimental group that received gait training using functional electrical stimulation and the control group that was treated by functional electrical stimulation and received gait training thereafter, differences between before and after the experiment were analyzed using paired sample t-tests and differences in changes after the experiment between the experimental group and the control group were analyzed using independent sample t-tests in order to compare the two groups with each other. Experimental results showed significant differences in weight bearing, balance and gait velocity between before and after the experiment in the experimental group(p<.05). In the control group, whereas weight bearing and gait velocity did not show any significant difference between before and after the experiment(p>.05), balance showed significant differences(p<.05). Weight bearing, balance and gait velocity change rates showed significant differences between the experimental group and the control group(p<.05). In conclusion, it was indicated that gait training using functional electrical stimulation is effective for enhancing stroke patients' weight bearing rates, balance abilities and gait velocity.
        4,000원
        475.
        2011.10 구독 인증기관·개인회원 무료
        Preservation of sperm is essential for long-term storage of valuable animal genetic resources and for the conservation of threatened mammalian species undergoing progressive extinction. In this study, using pig as a model system, we evaluated the feasibility of germ-plasm preservation via sperm cell lyophilization. We show that, pig sperm can be successfully lyophilized and stored in a liquid nitrogen-free condition for at least 6 months. Intracytoplasmic injection of lyophilized sperm (ICSI), stored at 4℃ for four months, into in vitro matured pig oocytes could successfully develop up to blastocyst stage (13.0±3.0%). Lyophilized sperm could also be stored at room temperature for at least three weeks without further compromising their in vitro development up to the blastocyst stage (14.6±3.2 vs. 16.6±5.1%; p>0.05). Blastocysts produced from ICSI of lyophilized sperm stored at 4℃ or room temperature contained similar number of cells per blastocyst (44.9±3.2 vs. 44.0±4.3; p>0.05) but was significantly lower than those produced from non-lyophilized fresh sperm (52.1±5.8 p>0.05). Interestingly, use of a custom-designed HEPES-buffered, calcium-free, defined medium for the lyophilization resulted in normal post-ICSI embryonic development up to blastula stage (23.4±2.8 vs. 24.0±2.9%) and, the resultant blastocysts contained similar number of cells per blastocyst (47.9±4.3 vs. 50.6±7.0) compared to those generated from non-lyophilized fresh sperm (p>0.05). These lyophilized sperm could also be stored at room temperature for at least three weeks with slight reduction in post-ICSI embryonic development (19.6±1.4%). Therefore, these results suggest that, pig sperm could be successfully and efficiently lyophilized for their long-term storage at 4℃. Lyophilization of sperm could be a practical option for long-term storage of mammalian germ-plasm.
        476.
        2011.10 구독 인증기관·개인회원 무료
        Autophagy, the process of bulk degradation and recycling of long-lived proteins, macromolecular aggregates, and damaged intracellular organelles, has recently been shown to be important for pre-implantation development and cavitation in mouse embryos. This study investigated the occurrence of autophagy and its importance in determining the in vitro development of pig embryos produced by in vitro fertilization (IVF) or parthenogenetic activation (PA). Western blot analysis for autophagy marker, microtubule associated protein light chain 3 (MAP-LC3), revealed the temporal pattern of LC3-conversion with intense changes during 10 20 h post-insemination and at morula-blastocyst transition in pig embryos. Specific inhibition of autophagy in 2 4 cell stage pig embryos, by treatment with 3-methyladenine (3MA), did not affect their embryonic development up to morula stage (p>0.05) but completely blocked their progression to the blastocyst stage (0.0±0.0 vs. 28.5±1.7% p<0.05). On the other hand, autophagy-inhibition in morula stage embryos significantly inhibited the formation of blastocoel (14.9±3.6 vs. 37.5±7.2%) and reduced the proportion of expanded blastocysts (5.6±2.6 vs. 29.6± 4.6% p<0.05). TUNEL assay revealed that autophagy-inhibited embryos had significantly increased indices of apoptosis (10.2±0.4 vs. 2.3±0.2) and DNA fragmentation (0.8± 0.1 vs. 0.3±0.1) than those of controls (p<0.05). Interestingly, while anti-oxidants reduced (p<0.05) the apoptosis and improved the blastocyst formation rate in pig embryos, it had no influence (p>0.05) on the expression of MAP-LC3. These data therefore, suggest that autophagy may have essential role during blastocyst formation in pig embryos.
        477.
        2011.10 구독 인증기관·개인회원 무료
        The nematicidal activity of Phellodendron amurense rhizome-derived materials (methanol extract) toward Meloidogyne Spp. second-stage juveniles (J2) and these effects on Cucumis sativus and Cucumis melo. Results were compared with these of fosthiazate. J2 was examined using 24-well plate tests, pot bioassays (C. sativa and C. melo) and Field trials (C. melo). In 24-well plate test with J2, methanol extract of P. amurense exhibited 98.7% and 69.8% mortality at 0.25 and 0.125 mg/ml toward J2, respectively, whereas Fosthiazate showed 100% mortality at 1 mg/ml. In pot bioassays with J2, P. amurense rhizome methanol extract gave 79.5% and 57.4% mortality at 2ℓ/m2(1,000x) and 2ℓ/m2(2,000x)/3kg soil from C. sativa and 73.7% and 53.3% mortality at 2ℓ/m2(1,000x) and 2ℓ/m2(2,000x)/3kg soil from C. melo, respectively. In Field test at C. melo in greenhouse showed 55.1% and 26.9% mortality at 2ℓ/m2(1,000x) and 2ℓ/m2(2,000x) applied soil. P. amurense rhizome-derived materials, merit further study as potential root-knot nematode control agents because of their nematicidal activity.
        478.
        2011.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Polyacrylonitrile-based carbon nanofibers (CNFs) containing Ti and Mn were prepared by electrospinning. The effect of metal content on the hydrogen storage capacity of the nanofibers was evaluated. The nanofibers containing Ti and Mn exhibited maximum hydrogen adsorption capacities of 1.6 and 1.1 wt%, respectively, at 303 K and 9 MPa. Toward the development of an improved hydrogen storage system, the optimum conditions for the production of metalized CNFs were investigated by characterizing the specific surface areas, pore volumes, sizes, and shapes of the fibers. According to the results of Brunauer-Emmett-Teller analysis, the activation of the CNFs using potassium hydroxide resulted in a large pore volume and specific surface area in the samples. This is attributable to the optimized pore structure of the metal-containing polyacrylonitrile-based electrospun CNFs, which may provide better sites for hydrogen adsorption than do current adsorbates.
        4,000원
        479.
        2011.06 구독 인증기관 무료, 개인회원 유료
        The current study was conducted in order to investigate promotional effects of herbal extracts on hair growth in an animal model of mice. There were four experimental groups, including distilled water (DW) as a negative control (NC), 3% minoxidil (MXD) as a positive control (PC), 50% ethanol (EtOH) as a vehicle control (VC), and herbal extract (HE) as the experimental treatment (E). The HE was extracted with ethanol from plants, including Gardenia, Mentha arvensis, Rosemary, and Lavender. Six-week-old C57BL/6 male mice were shaved with an electric clipper and the test materials were topically treated with 0.2 ml per mouse daily for three weeks. Photographic evaluation of hair re-growth was performed weekly during a period of three weeks. The number of mast cells was counted on the dorsal skin section of mice. The enzymes, alkaline phosphatase (ALP) and γ-glutamyl transpeptidase (γ-GT), were determined using a biochemical autoanalyzer. No clinical signs were observed in any of the experimental groups. As a result of photometric analysis, topical application of HE to dorsal skin for two weeks resulted in significantly faster acceleration of hair regrowth, compared with that of the NC or VC group (P<0.05). The PC and E groups showed a significant decrease in mast cell population, compared to the NC group. Activities of ALP and γ-GT were significantly increased in the PC and E groups, compared to the NC or VC group (P<0.05). Taken together, these results suggest that the herbal extract may have hair-growth promoting activity equal to that of MXD.
        4,000원