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91.
So Gun Hong Min Kyu Kim Goo Jang Hyun Ju Oh Jung Eun Park Jung Taek Kang Ok Jae Koo Teoan Kim Mo Sun Kwon Bon Chul Koo Jeong Chan Ra Dae Yong Kim CheMyong Ko Byeong Chun Lee 《Genesis (New York, N.Y. : 2000)》2009,47(5):314-322
Dogs (Canis familiaris) share many common genetic diseases with humans and development of disease models using a transgenic approach has long been awaited. However, due to the technical difficulty in obtaining fertilizable eggs and the unavailability of embryonic stem cells, no transgenic dog has been generated. Canine fetal fibroblasts were stably transfected with a red fluorescent protein (RFP) gene‐expressing construct using retrovirus gene delivery method. Somatic cell nuclear transfer was then employed to replace the nucleus of an oocyte with the nucleus of the RFP‐fibroblasts. Using this approach, we produced the first generation of transgenic dogs with four female and two male expressing RFP. genesis 47:314–322, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
92.
Se Ryun Kwon Yue Jai Kang Dong Jin Lee Eun Hye Lee Yoon Kwon Nam Sung Koo Kim Ki Hong Kim 《Molecular biotechnology》2009,42(2):154-159
Vibrio anguillarum ghosts (VAG) were generated, for the first time, using a conjugation vector containing a ghost bacteria inducing cassette,
pRK-λPR-cI-Elysis, in which the expression of PhiX174 lysis gene E was controlled by the P
R
/cI regulatory system of lambda phage. By scanning electron microscopy, holes ranging 80–200 nm in diameter were observed in
the VAG. To avoid the presence of bacterial genomic DNA and an antibiotic resistance gene in the final VAG product, we constructed
a new dual vector, pRK-λPR-cI-E-SNA, containing the E-mediated lysis cassette and the staphylococcal nuclease A (SNA)-mediated DNA degradation cassette, and generated safety-enhanced VAG for use as a fish vaccine. 相似文献
93.
After measuring toluene adsorption (15.7 mg-toluene/g-material), water holding capacity (18.5%), organic content (53.8%),
specific surface area (18.1 m2/g-material), and microbial attachment, crab shells were chosen as the main packing material for a biofilter design. The crab
shells, cheap and abundant in the Gangneung area, also have relatively rigid structure, low density, and ability to neutralize
acids generated during mineralization of toluene. Since towel scraps have water holding capacity as high as 301.2%, 10% of
the total packing was supplemented with them to compensate for low water holding capacity of the crab shells. The biofilter
fed with defined chemical medium under 0.8∼1.3 mg/L of inlet toluene concentration and 18 seconds of residence time showed
satisfactory removal efficiency of over 97% and 72.8 g/h·m3 of removal capacity. For the purpose of deceasing operation costs, leaf mold solution was tried as an alternative nutrient
instead of a defined chemical medium. The removal efficiency and removal capacity were 85% and 56.3 g/h·m3, respectively, using the same inlet toluene concentration and residence time. This research shows the possibility of recycling
crab shell waste as packing material for biofilter. In addition, leaf mold was able to serve as an alternative nutrient, which
remarkably decreased the operating cost of the biofilter. 相似文献
94.
Sung-Hwan Jo Dal-Hoe Koo Jihyun F Kim Cheol-Goo Hur Sanghyeob Lee Tae-jin Yang Suk-Yoon Kwon Doil Choi 《BMC plant biology》2009,9(1):42
Background
Tandemly repeated DNA, also called as satellite DNA, is a common feature of eukaryotic genomes. Satellite repeats can expand and contract dramatically, which may cause genome size variation among genetically-related species. However, the origin and expansion mechanism are not clear yet and needed to be elucidated. 相似文献95.
So-Jung Kwon Kyuyong Han Suhyun Jung Jong-Eun Lee Seongsoon Park Yong-Pil Cheon Jade Hyunjung Lim 《BMC biotechnology》2009,9(1):73
Background
MPG is a cell-permeable peptide with proven efficiency to deliver macromolecular cargoes into cells. In this work, we examined the efficacy of MPG as an N-terminal tag in a fusion protein to deliver a protein cargo and its mechanism of transduction. 相似文献96.
Peter Chi Youngho Kwon Dana N. Moses Changhyun Seong Michael G. Sehorn Akhilesh K. Singh Hideo Tsubouchi Eric C. Greene Hannah L. Klein Patrick Sung 《DNA Repair》2009,8(2):279-284
Genetic studies in budding and fission yeasts have provided evidence that Rdh54, a Swi2/Snf2-like factor, synergizes with the Dmc1 recombinase to mediate inter-homologue recombination during meiosis. Rdh54 associates with Dmc1 in the yeast two-hybrid assay, but whether the Rdh54–Dmc1 interaction is direct and the manner in which these two recombination factors may functionally co-operate to accomplish their biological task have not yet been defined. Here, using purified Schizosaccharomyces pombe proteins, we demonstrate complex formation between Rdh54 and Dmc1 and enhancement of the recombinase activity of Dmc1 by Rdh54. Consistent with published cytological and chromatin immunoprecipitation data that implicate Rdh54 in preventing the non-specific association of Dmc1 with chromatin, we show here that Rdh54 mediates the efficient removal of Dmc1 from dsDNA. These functional attributes of Rdh54 are reliant on its ATPase function. The results presented herein provide valuable information concerning the Rdh54–Dmc1 protein pair that is germane for understanding their role in meiotic recombination. The biochemical systems established in this study should be useful for the continuing dissection of the action mechanism of Rdh54 and Dmc1. 相似文献
97.
Chunmei Li Eliane Beauregard-Lacroix Christine Kondratev Justine Rousseau Ah Jung Heo Katherine Neas Brett H. Graham Jill A. Rosenfeld Carlos A. Bacino Matias Wagner Maren Wenzel Fuad Al Mutairi Hamad Al Deiab Joseph G. Gleeson Valentina Stanley Maha S. Zaki Yong Tae Kwon Michel R. Leroux Philippe M. Campeau 《American journal of human genetics》2021,108(1):134-147
98.
Sang Koo You Dae Hyuk Kwon Yong-ik Park Sun Myong Kim Myung-Hoon Chung Chul Koo Kim 《Journal of theoretical biology》2009,261(3):494-500
We present a particle-based simulation study on two-component swarms where there exist two different types of groups in a swarm. Effects of different parameters between the two groups are studied systematically based on Langevin's equation. It is shown that the mass difference can introduce a protective behavior for the lighter members of the swarm in a vortex state. When the self-propelling strength is allowed to differ between two groups, it is observed that the swarm becomes spatially segregated and finally separated into two components at a certain critical value. We also investigate effects of different preferences for shelters on their collective decision making. In particular, it is found that the probability of selecting a shelter from the other varies sigmoidally as a function of the number ratio. The model is shown to describe the dynamics of the shelter choosing process of the cockroach–robot mixed group satisfactorily. It raises the possibility that the present model can be applied to the problems of pest control and fishing using robots and decoys. 相似文献
99.
Although the health benefits of dietary antioxidants have been extensively studied, their potential negative effects remain unclear. L-Ascorbic acid 6-palmitate (AAP), a synthetic derivative of ascorbic acid (AA), is widely used as an antioxidant and preservative in foods, vitamins, drugs, and cosmetics. Previously, we found that AA exerted an antitumor effect by protecting inhibition of gap-junctional intercellular communication (GJIC), which is closely associated with tumor progression. In this study, we examined whether AAP, an amphipathic derivative of AA, has chemopreventive effects using a GJIC model. AAP and AA exhibited dose-dependent free radical-scavenging activities and inhibited hydrogen peroxide (H2O2)-induced intracellular reactive oxygen species (ROS) production in normal rat liver epithelial cells. Unexpectedly, however, AAP did not protect against the inhibition of GJIC induced by H2O2; instead, it inhibited GJIC synergistically with H2O2. AAP inhibited GJIC in a dose-dependent and reversible manner. This inhibitory effect was not due to the conjugated lipid structure of AAP, as treatment with palmitic acid alone failed to inhibit GJIC under the same conditions. The inhibition of GJIC by AAP was restored in the presence of mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitor U0126, but not in the presence of other signal inhibitors and antioxidant (PKC inhibitors, EGFR inhibitor, NADPH oxidase inhibitor, catalase, vitamin E, or AA), indicating the critical involvement of MEK signaling in the GJIC inhibitory activity of AAP. Phosphorylation of ERK and connexin 43 (Cx43) was observed following AAP treatment, and this was reversed by U0126. These results suggest that the AAP-induced inhibition of GJIC is mediated by the phosphorylation of Cx43 via activation of the MEK–ERK pathway. Taken together, our results indicate that AAP has a potent carcinogenic effect, and that the influence of dietary antioxidants on carcinogenesis may be paradoxical. 相似文献
100.