검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 457

        201.
        2012.10 구독 인증기관·개인회원 무료
        Varieties of Bacillus thuringiensis (Bt) crystal proteins, Cry proteins, have so far been found as one of the most successful biological control agents which are safe to natural environments for a long time. Recently, cry genes encoding these Cry proteins have been widely applied for construction of transgenic crops resistant to pest insects. In this study, through the 3D structure prediction and accompanying mutagenesis study for the Mod-Cry1Ac, 7 and 16 amino acid residues from domain I and II, respectively, responsible for its insecticidal activity against larvae of Spodoptera exigua and Ostrinia furnacalis were identified. To construct novel cry genes with improved insecticidal activity, we randomly mutated these 23 amino acid sequences by in vitro muti site-directed mutagenesis, resulting in totally 24 mutant cry genes. For further characterization, these mutant cry genes were expressed as a fusion protein with polyhedrin using baculovirus expression system. SDS-PAGE analysis of the recombinant polyhedra revealed that expressed Cry proteins was occluded into polyhedra and activated stably to 65 kDa by trypsin. In the further study, we plan to investigate their insecticidal activity against Plutella xylostella, S. exigua and O. furnacalis larvae.
        203.
        2012.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Meedon rice varieties are important for local adaptability, grain quality and market availability, and have been grown in Myanmar for centuries. Because of temporal variability and spatial heterogeneity, Meedon rice varieties in rainfed lowland areas may be diverse. However, information on diversity of Meedon rice germplasm is limited. This study was carried out to assess genetic diversity and to analyze population structure of Meedon rice germplasm conserved in Myanmar Seed Bank using SSR markers. For assessing genetic diversity, 154 accessions of Meedon rice germplasm were analyzed with nine SSR markers. A total of 86 alleles were detected with an average of 9.6 alleles per locus. All the loci were found to be polymorphic, and there were considerable genetic variation among accessions with mean values of expected heterozygosity (HE) = 0.5774 and polymorphic information content (PIC) = 0.5496. High frequency of rare alleles was identified, among which 35 unique (accession-specific) alleles were observed. Based on cluster analysis, rice accessions were mainly clustered into two groups, and as a result of model-based analysis, two distinct genetic populations and an admixture were classified. This result indicated that SSR markers have proved to be useful markers for detecting genetic diversity in Meedon rice, and the occurrence of a considerably high number of rare and unique alleles in the germplasm indicates their potentiality as a reservoir of rare genotypes for use. Unique alleles are also important because they may be diagnostic of a particular type of genotype for identification.
        4,000원
        205.
        2012.06 구독 인증기관·개인회원 무료
        Among laboratory animals, pigs are anatomically and physiologically closer to human. Transgenic (TG) pigs can be widely applied as models of human diseases. Many researchers created TG pigs which have specific modified genome under a constitutively active promoter. A constitutively active promoter is effective to express a target gene, but the uncontrollable expression often results in unwanted outcomes. In this study, as a way to solve these problems, we tried to regulate the expression of target genes by tetracycline (Tet) on/off system. We tested the operation of Tet on/off system in TG donor cells. Miniature porcine fetal fibroblasts were transfected with universal doxycycline- inducible vector and an enhanced green fluorescent protein (eGFP) was used as the target gene. The induced transgene expression by doxycycline was detected on fluorescence microscopy. On one day after 1 μg/ml doxycycline treatment, the fluorescence intensity for TG cells was increased. And we then performed Somatic Cell Nuclear Transfer (SCNT) to confirm the working of Tet on/off system in the porcine SCNT-TG embryos. Total 649 transgenic porcine SCNT embryos were made. From these, 64 of SCNT embryos used in invitroculturewith1 μg/mldoxycycline. Among these porcine SCNT-TG embryos, 39 embryos (60.9%) were cleaved. Finally, 15 transgenic porcine SCNT embryos developed blastocyst. Induced transgene expression was observed all of cleaved embryos and blastocysts. The remaining 585 embryos were transferred to 6 surrogates. On 25 days after embryo transfer, two surrogates were diagnosed as pregnant (pregnancy rate =33.3%). On day 113 (one day prior to delivery), we obtained six cloned TG piglets from first pregnant surrogate. Unfortunately, all TG piglets died because their surrogate died suddenly at delivery time. However, we could obtain the TG cell lines from the cloned TG piglets. Being analyzed by PCR, all piglets were found to be eGFP gene targeted. Now, second pregnant surrogate have maintained at 80 days after embryo transfer and shown more than three embryonic sacs. This data suggested that, Tet on/off system can control target gene expression in transgenic porcine SCNT embryos. This result has presented new possibilities of regulation of target gene expression in cloned TG pigs by Tet on/off system. * This work was supported by a grant from Next-Generation BioGreen 21 program (# PJ008121), Rural Development Administration, Republic of Korea.
        206.
        2012.06 구독 인증기관·개인회원 무료
        Neural stem cells (NSCs) are self-renewing tripotent cell populations and have capacity of neuronal (neurons) and glial (astrocytes and oligodendrocytes) differentiation. Many researchers have reported that NSCs have therapeutic effects in neurological disease by transplantation. However, it is not easy to obtain NSCs in vitro. Recently, Yamanaka and colleagues showed that somatic cells could be reprogrammed into pluripotent state by enforcing reprogramming factors. Induced pluripotent stem (iPS) cells undergo unlimited self-renewal and have differentiation potential into various types of cells like embryonic stem cells. Direct differentiation into a specialized cell types from iPS cells hold considerable promise for regenerative medicine as well as basic research. Here, we induced differentiation of iPS cells into NSCs in vitro and in vivo, which were compared with embryonic stem (ES) cell-derived NSCs and brain derived NSCs. NSCs from ES and iPS cells were morphologically indistinguishable from brain derived NSCs and stained positive for NSCs markers Nestin and Sox2. ES cells derived NSCs were transcriptionally distinguishable from brain derived NSCs. However, global gene expression pattern were similar but distinct between iPS derived NSCs and brain derived NSCs. Moreover, iPS derived NSCs were spontaneously aggregated upon passaging, formed ES cell like colonies, and finally reactivated Oct4-GFP. The spontaneously reverted GFP-positive cells (iPS-NSC-iPS) expressed similar levels of pluripotency markers (Oct4,Nanog) to ES and iPS cells, and could form germ line chimera. One possible explanation for this phenomenon is that spontaneously re-reprogramming was associated with transgene re-activation when iPS cells were differentiated into NSCs. However, NSCs from dox-inducible iPScells could not be reprogrammed into pluripotent state without doxycycline. Taken together, iPS derived NSCs were morphologically and similar to brain derived NSCs, but differ in gene expression pattern and maintenance. * This work was supported by the Next Generation Bio-Green21 Program funded by the Rural Development Administration (Grant PJ008009).
        207.
        2012.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was carried out to identify how a self-stretching exercise program affects pain for each body area, pain relief and job satisfaction for care workers. 20 of 40 care workers with musculoskeletal symptom were randomly selected and participated a self-stretching exercise program consisting of 15 motions. The intervention was done five times or more per weeks for 8 weeks and 1 session lasted within 15 minutes. 'Musculoskeletal symptom survey table' of the Korea Occupational Safety and Health Agency(KOSHA) and JDI(Job Descriptive Index) was used for pain on the musculoskeletal symptom and job satisfaction. Survey were done twice before and after the program. The result of this study showed that self-stretching exercise program group(SSPG) relieved from pain significantly in the shoulders(p<.01) and lumbar(p<.05), comparing to the non selfstretching exercise program group(NSPG). Although no significant difference on variations in the JDI appeared in SSPG, the significant reduction appeared from the colleague relationship and organization in NSPG(p<.05). SSPG showed the significant increase on variations in JDI from the job and organization comparing to NSPG. Especially, the improvement on satisfaction for the organization was shown(p<.05). Accordingly, the self-stretching exercise program for care workers can be said to positively affect the overall pain relief and increase on the JDI.
        4,000원
        208.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        꼬마배나무이 (Cacopsylla pyricola)에 저항성 품종육성을 위한 육종재료를 선발코자 월동형 성충수, 단과지내의 산란수, 과총엽내의약충수 및 수관 전체적인 그을음 발생정도를 15개 종 및 종간잡종133개 유전자원을 대상으로 조사하였다. 월동형 성충수는 Pyrus.calleryana 4.6마리, 단과지내 산란수는 P. calleryana 0.3개, 과총엽내약충수는 P. calleryana 0마리, 그리고 그을음 발생정도는 P.betulaefolia, P. calleryana, P. communis, P. hybrid (P.pyrifolia × P.communis), P. lindleyi 0으로 발생 및 피해정도가 가장 낮았으며 종간의 차이가 뚜렷하였다. 전체적으로 대목으로 이용하고 있는 콩배인P. calleryana와 P. betulaefolia가 조사 대상 유전자원 중 가장 높은 항객성(antixenosis)을 보였으나 품질개량에 많은 기간이 요구됨에 따라 실용적으로는 서양배(P. communis) 중 ‘Conference', 'Cascade','Bosc', 'Winter Nelis' 가 가장 낮은 발생 및 피해정도를 보여 꼬마배나무이 저항성 품종 육성을 위한 좋은 육종재료로 판단되었다.
        4,000원
        209.
        2011.11 구독 인증기관 무료, 개인회원 유료
        바다에 기름오염 사고가 발생하면 여러 가지 방제 방법 중 물리적 회수 방법을 우선적으로 사용하고 유처리제는 최후 수단으로 고려하는 경향이 있다. 유처리제는 수중으로 기름이 신속히 분산되도록 하여 해수면으로부터 제거하는 방법이다. 해수면으로부터 신속히 기름을 제거하는데 대한 유처리제의 효용성은 널리 증명되어 왔으나 아직도 대부분의 국가들은 해양환경에 미치는 독성을 우려하여 적극적인 사용을 하지 않고 있는 실정이다. 보고된 자료에 의하면 유처리제 사용 후 수중생물에 대한 독성은 발견되지 않았으며, 유처리제와 혼합된 기름이 기 름 그 자체보다 독성이 더 크게 나타나지 않았다. 멕시코만 기름유출 사고 시 미국 정부와 BP사는 최대한 해안에 기름이 도달하지 않는데 중 점을 두고 해수면뿐만 아니라 수중의 기름에 대해서도 유처리제를 사용하였다.
        3,000원
        212.
        2011.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In using both hands, everyone dominantly use one hand and it is called left-handedness or right-handedness person. Measurements of grip and pinch strength provide objective indexes to represent functional integrity of the upper extremity. This study was conducted for thirty female college students(19 right-handedness and 11 lefthandedness). For assessment of the type of handedness, questionnaire was used; for grip strength, Jamar dynamometer was used; for pinch strength, Jamar pinch gauge was used. In right handedness, the grip and pinch strength of the dominant right hand was significantly higher than those of the non-dominant hand. In addition, regular exercises were shown to give influences on reduction of strength gaps between dominant and non-dominant hands. In both groups of left and right handedness, the grip and pinch strength of the dominant hand were significantly higher than those of the non-dominant hand, and regular exercises were shown to give influences on reduction of strength gaps between dominant and non-dominant hand.
        4,000원
        215.
        2010.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was to investigate the effects of upper and lower limb composing patterns of PNF(proprioceptive neuromuscular facilitation) on the static balance ability by 20 subjects for 6 weeks. This study was measured left one leg standing and right one leg standing with closed eyes on Good Balance system. These results led us to the conclusion that the mean speed of X, Y direction, COP(center of Pressure) velocity moment showed a statistical decrease when applying post-exercise. The above results from this study indicated that upper and lower limb composing patterns of PNF exercise has improved the static balance ability. As a result, this study showed that upper and lower limb composing patterns exercise improve the ability of balance in young adults. Based on this study, it may be applied to old people.
        4,000원
        216.
        2010.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aims to reveal how EA affects BAX and NF-kB involved in cell deaths from global ischemia, and to do this, observes the changes of BAX and NF-kB caused by EA application after transient global ischemia. The experimental method is to give rise to global ischemia and apply EA to 27 SD rats with the particulars of being six-week-old, male, around-300 gram-weighing, and adapted to laboratory environment for more than a week, and divide them into three groups, that is, GV20 EA group(n=9), L14 EA group(n=9), no-treatment GI group(n=9), and then observe their changes of BAX and NF-kB at the time lapse of 6 hours, 9 hours and 12 hours after ischemia, using western blotting. The numerical decrease of BAX expression at the time lapse of 9 hours after EA application, though not statistically significant, was observed in GV20 EA group and L14 EA group, and the NF-kB expression appeared statistically significant decrease in GV20 EA group and L14 EA group, but the expression was higher in the group with EA application. Therefore, EA application at the early phase of global ischemia is considered to affect BAX and NF-kB and play a positive role in decreasing apoptosis and cell deaths by inflammation.
        4,000원
        218.
        2010.05 구독 인증기관·개인회원 무료
        The porcine reproductive and respiratory syndrome virus (PRRSV) has three major structural proteins which designated as GP4, GP5, and M. They have been considered very important to arouse the humoral and cellular immune responses against PRRSV infection and proposed to be the excellent candidate proteins in the design of PRRS bioengineering vaccine. However, the PRRSV structural proteins are produced in low levels in the infected cells because it forms insoluble protein and possesses several transmembrane regions. To overcome this problem, we fused the GP4, GP5, and M with SUMO (Small ubiquitin-related modifier), and expressed the fused gene in Bm5 cells and silkworm larvae. Expression of the proteins were analyzed by 12% SDS-PAGE and western blotting using 6xHis tag and porcine anti-PRRSV antibodies. In results, SUMO fused proteins were expressed at a high level in Bm5 cells. The levels of protein using the silkworm larvae is higher than that using Bm5 cells. The fused protein was purified by Ni-NTA affinity chromatography. This study demonstrated that SUMO, when fused with PRRSV structural proteins, was able to promote its soluble expression. This may be a better method to produce PRRSV structural proteins for vaccine development.
        219.
        2010.05 구독 인증기관·개인회원 무료
        Five field-collected populations (TR-CP, UR-CP, JR-CP, GR-CP, and BR-CP colonies) of northern house mosquito, Culex pipiens pallens, identified by polymer chain reaction (PCR) were tested for susceptibility to 10 different insecticides by direct-contact mortality bioassay in comparison with an insecticide-susceptible KS-CP strain. Marked regional variations of insecticide susceptibility were observed. Extremely high to high levels of resistance were obtained: bifenthrin, resistance ratio (RR) = 1–520; β-cyfluthrin, RR = 16–397; α -cypermethrin, RR = 9–343; deltamethrin, RR = 1–40; etofenprox, RR = 2–42; permethrin, RR = 2–12; chlorpyrifos, RR = 2–675; fenitrothion, RR = 0.5–364; and fenthion, RR = 2–360. All of the colonies were susceptible to one or more of the insecticides examined. These results indicate that careful selection and rotational use of these insecticides should result in continued satisfactory control against field populations of northern house mosquito.
        220.
        2010.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        2 week study was conducted to investigate the effects of Interferential Current(IC) and Kaltenborn-Evjenth Orthopedic Manual Therapy(KEOMT) on functional constipation. Interventions were applied to spinal segments between T9-L2 which provides innerva˗ tions to the gastrointestinal tract. Subjects(n=24) were randomly allo˗ cated to two treatment groups: the IC group or the KEOMT group. Results for the IC therapy demonstrated significant decrease with the colonic transit time(CTT) as well as scores on the constipation assessment scale(CAS). The frequency of defecations per week had increased significantly(p<0.05). The KEOMT displayed decreased CTT in the left colon region. The scores on the CAS were reduced and frequency of defecations per week had increased significantly (p<0.05). This study not only showed that both modes of therapy improved symptoms of constipation, but also optimized gastrointesti˗ nal content movement, eventuating in a more normalized CTT. In conclusion, both the IC therapy and the Kaltenborn-Evjenth Orthopedic Manual Therapy have shown to be effective interventions for improving functional constipation.
        4,000원